Discover the detailed structure, types (Smooth ER & Rough ER), and vital functions of the endoplasmic reticulum.

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The endoplasmic reticulum is an important part of a cell that makes and transports proteins and fats.

It comes in two types: smooth endoplasmic reticulum and rough endoplasmic reticulum.

This blog will explain the structure and function of the endoplasmic reticulum and why it is essential for cell survival and growth.

Endoplasmic Reticulum

The endoplasmic reticulum (ER) is one of the cell organelles. Organelle means ‘the little organs’.

Organelles have a definite structure and defined functions in the cell, and have the same status in the cell as the organs have in the body of an animal or a plant.

The endoplasmic reticulum is an irregular network of double-membrane tube-like structures, whose primary function is to provide a supporting framework to the cell.

It is of two types: rough and smooth endoplasmic reticulum.

This post will explore the structure and functions of both the rough and the smooth endoplasmic reticulum.

Endoplasmic Reticulum

STRUCTURE AND FUNCTION OF ENDOPLASMIC RETICULUM

We use an electron microscope to reveal the existence of the endoplasmic reticulum (ER) within the cell due to its fine structure.

Structure of Endoplasmic Reticulum

• It is an irregular network of double-membrane tube-like structures distributed over the entire cytoplasm in a cell.
• It is continuous with the cell or plasma membrane on the outside and the nuclear membrane on the inside.
• At its outer end, the endoplasmic reticulum (ER) is connected with the cell membrane.
• At the inner end, it is connected with the nuclear membrane.
• It is continuous with the cell or plasma membrane on the outside and the nuclear membrane on the inside
• The endoplasmic reticulum is of two types – rough and smooth. It appears uneven when the particle-like ribosomes are attached to it and appears smooth without them.

Common Functions of Smooth and Rough Endoplasmic Reticulum

• Its primary function is to form the supporting framework of the cell.
• It also serves as a pathway for the distribution of the material (proteins and fats) from one part of the cell to the other.

Specific Function of Rough Endoplasmic Reticulum

• Due to the presence of ribosomes, the rough endoplasmic reticulum synthesizes proteins and lipids, helping regenerate cell membranes. We call this process membrane biogenesis (‘Biogenesis’ means ‘generation of a substance by living matter’).

Structure and function of the endoplasmic reticulum in tabular form

Structure and function of the endoplasmic reticulum (ER)

RIBOSOMES AND THEIR FUNCTION

Ribosomes are numerous small granules that either float freely in the cytoplasm or attach to the membranes of the endoplasmic reticulum, giving it a rough appearance. These tiny, single-walled, dense, spherical structures primarily consist of RNA (Ribonucleic Acid) and proteins.

Ribosomes actively synthesize proteins, which are essential for cell growth and function. They assemble amino acids into proteins based on genetic instructions. Because of this vital function, cells refer to ribosomes as the “factories” or “sites” of protein synthesis. Without ribosomes, cells cannot produce the proteins needed for various life processes, such as repairing tissues, maintaining cell structure, and enabling enzyme activity.

The video from Bodhaguru explains the structure and function of the endoplasmic reticulum using a 3D model.

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Struggling to understand cell biology? Learn the structural and functional differences between plant and animal cells in simple terms. 

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All living things, whether plants or animals, are composed of microscopic structures called cells. The basic structure of a cell is similar in all living organisms. However, there are some key differences between a plant and an animal cell.

Both plant and animal cells contain a cell membrane, cytoplasm, nucleus, endoplasmic reticulum, Golgi apparatus, mitochondria, ribosomes, and lysosomes.

However, there are structural and quantitative differences between plant and animal cells regarding these organelles.

Difference Between Plant and Animal Cells

The differences between plant and animal cells can be categorized into structural and quantitative.

Structural Differences:

Plant cells have a cell wall, chloroplasts, and a large central vacuole, while animal cells lack these but contain centrioles.

Quantitative Differences:

Plant cells have fewer, larger vacuoles, whereas animal cells have many small vacuoles. Mitochondria are more abundant in animal cells, and lysosomes are common in animals but rare in plant cells.

Difference between plant and animal cells in tabular form

STRUCTURAL DIFFERENCES BETWEEN PLANT AND ANIMAL CELL

• Cell Wall – Present in a plant cell but absent in an animal cell. The cell wall is an extra covering that surrounds the cell membrane of a plant cell. It is made of stiff, non-living material called cellulose. Unlike the cell membrane, it is freely permeable and allows all substances in solution form to pass through it. The cell wall provides rigidity and protection to the cell.

• Centrosome – Absent in a plant cell but present in animal cells. Animal cells possess a centrosome, a cell organelle that helps in cell division. It is a clear area of cytoplasm close to the nucleus from which spindle fibers develop during cell division, both in mitosis and meiosis.
  

  Structure of a Generalized Animal Cell with Various Organelles

• Vacuole – Present in both plant and animal cells, but their structure varies. One of the most prominent differences between plant and animal cells is in the structure of vacuoles. Vacuoles are certain clear spaces in the cytoplasm. They contain water and various substances in the solution state. These bubble-like sacs are bounded by a single membrane called ‘Tonoplast’. Vacuoles in plant cells are larger in size and fewer in number. They occupy most of the space inside a plant cell and provide turgidity and rigidity to the cell. Vacuoles play an important role in the excretion and secretion of the cell. Whereas, in animal cells, vacuoles are absent; if present, they are smaller in size and more in number.
• Plastids – Present in a plant cell but absent in animal cells. Plastids manufacture and store food in plant cells. They occur in different shapes – oval, spherical, and disc-shaped. These are double-membrane organelle which has DNA and ribosomes. Therefore, like mitochondria, plastids are also semi-autonomous organelles.

QUANTITATIVE DIFFERENCES BETWEEN PLANT AND ANIMAL CELLS

• Size – Plant cells are usually large with distinct outlines, whereas animal cells are small with less distinct boundaries.
  

  Structure of a Generalized Plant Cell showing various Organelles

• Cytoplasm – Animal cell cytoplasm is denser and granular in comparison to that of plant cells.
• Arrangement of Cytoplasm – In plant cells, there is a thin lining of cytoplasm mostly pushed to the periphery, whereas in animal cells, cytoplasm fills almost the entire cell.

Have you ever thought about why a plant cell has a cell wall and a chloroplast?

Imagine standing erect without bones or muscles. Also, can your body make its own food? But a green plant stands erect without having any bones and prepares its food.

A plant cell has special parts that make these things possible. It has a cell wall and chloroplasts. The cell wall stiffens the plant. The chloroplasts help it to make food.

Structure of generalized plant and animal cells….Selftution

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Master the building blocks of life with clear, step-by-step guides. Welcome to Selftution.com – simplifying biology for students and curious minds!

So, let’s begin.

Living things consist of tiny living parts or compartments called cells. A cell itself consists of certain tiny parts or structures called organelles. These organelles perform various life functions within the cell.

This post will discuss the structure and function of the cell and its organelles.

Click here for the definition of the cell, the discovery of the cell, and cell theory

STRUCTURE AND FUNCTION OF A CELL

The cell provides structure and performs all the life functions of living things. Cells vary greatly in shape and structure.

Also, plant and animal cells are not alike. These may be disc-like, rectangular, flat, cuboidal, thread-like, branched, or even irregular. The structure of a cell is often related to the function it performs.

• Red blood cell in humans has the shape of a biconcave disc. This helps it to pass through narrow capillaries and transport oxygen.

Red Blood Cells

• White blood cells in humans are of irregular shape, which is more like an amoeba. This helps it to squeeze out through the capillary walls to fight pathogens.

Various types of white blood cells

• A nerve cell is of an irregular shape with a long, thread-like structure. This helps it to conduct impulses from distant parts of the body to the brain.

Nerve Cell

• The muscle cell is long and possesses elasticity. This feature helps it contract and relax to pull or squeeze the parts.

Muscle cells

• Guard cells of stomata in the leaves have a shape similar to that of kidney beans. This helps them to perform the function of opening and closing the pore.

Stomata Guard Cell with open and closed pore

Back to >>>>Structure and Function of the Cell

GENERALIZED STRUCTURE OF CELL

Various kinds of cells have different shapes and structures based on the functions they perform. Yet, all of them show some basic structural plans. This basic representation of cells, showing all features, is called a generalized cell. The generalized cell differs for plants and animals due to the presence or absence of certain parts or organelles.

Definition of Generalized Cell –

The generalized cell is the basic representation of cell showing all parts and organelles which can be present in any specialized cell. It is a hypothetical cell for a quick understanding of the basic structure and function of the cell and its organelles.

Structure of a Generalized Plant Cell showing various Organelles

Structure of a Generalized Animal Cell with Various Organelles

All plant and animal cells consist of living and non-living parts.

The living part of the cell includes the cell membrane, the cytoplasm, and the nucleus. All three together are known as protoplasm. The non-living parts of the cell are granules and vacuoles.

The cytoplasm is embedded with tiny parts or structures called organelles. Organelle means ‘the little organs’. Organelles have definite structures and definite functions in the cell and have the same status in the cell as the organs have in the body of an animal or a plant.

Let us now discuss the different parts and organelles of the generalized cell of animals and plants in detail:

1. Cell Membrane or Plasma Membrane

The cell membrane is a very thin skin covering the cell. The cell membrane protects the cell and provides shape to it. It is made up of lipoprotein. There are very tiny holes in the cell or plasma membrane. It allows materials to enter and leave the cell through these tiny pores or openings. However, its permeability is selective. It means it allows certain substances to pass through it and prevents others.

The structure and function of a cell or plasma membrane are:

Structure and Function of the Cell or Plasma Membrane

Cell Wall: The cell wall is an extra covering that surrounds the cell membrane of a plant cell. It is made of stiff, non-living material called cellulose. The cell wall provides rigidity and protection to the cell. Unlike the cell membrane, it is freely permeable and allows all substances in solution form to pass through it. Animal cells do not have a cell wall.

The structure and function of a cell wall are:

Structure and Function of the Cell Wall

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2. Cytoplasm

The cytoplasm is a jelly-like, semi-liquid structure occupying most of the inside of the cell. It occupies the space between the cell membrane and the nucleus. Under a microscope, it appears to be colorless, partly transparent, and somewhat watery. It is a living part of the cell, and all the life functions take place in the cytoplasm. The living cytoplasm is always in a state of motion. The cytoplasm contains many important tiny structures called organelles, which perform various life functions.

The structure and function of the cytoplasm are:

Structure and Function of Cytoplasm

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3. Nucleus – The Control Center of the Cell

The nucleus is a spherical body present inside the cell. This structure is the control center of the cell, and its function is to regulate and coordinate the various life processes of the cell. Most cells have only one nucleus, but some cells, like those of muscles, have more than one nucleus.

The structure and function of the nucleus in the cell are:

Function and Structure of the Nucleus of the Cell

The nucleus comprises four parts – nuclear membrane, nuclear sap or nucleoplasm, nucleolus or nucleoli, and chromatin fibers.

Nuclear membrane – It is the delicate outermost covering layer of the nucleus. It separates the nucleus from the cytoplasm. A nuclear membrane, like the cell membrane, has tiny holes in it that allow the exchange of substances between the nucleus and the cytoplasm.

Nucleoplasm – It is the jelly-like fluid inside the nucleus. Chromatin fibers and nucleoli are embedded in the nucleoplasm.

Chromatin fibers – A network of thread-like structures called the chromatin network is present in the nucleoplasm. It consists of DNA (deoxyribonucleic acid) and proteins. At the time of cell division, the chromatin fibers develop into thick and ribbon-like, or rod-like structures called chromosomes. These chromosomes play an important role in carrying the genetic characters from the parents to the offspring.

Nucleolus or nucleoli – It is a dense, dark, granular structure without a membrane.  It consists of RNA (ribonucleic acid) and proteins. It is the site of ribosome formation; thus, we can call it the factory of ribosomes.

Back to >>>>Structure and Function of the Cell

STRUCTURE AND FUNCTION OF CELL ORGANELLES

Organelle means ‘the little organs’. Organelles have definite structures and definite functions in the cell and have the same status in the cell as the organs have in the body of an animal or a plant.

a. Endoplasmic Reticulum

The endoplasmic reticulum (ER) is so fine in structure that we can view it only through an electron microscope. It is of two types – rough and smooth. The endoplasmic reticulum appears uneven due to the presence of particles like ribosomes attached to its surface. On the other hand, without them, it appears smooth. The function of the smooth and rough endoplasmic reticulum is to form the supporting framework of the cell. Due to the presence of ribosomes, the endoplasmic reticulum synthesizes proteins and lipids, which help in regenerating cell membranes. This process is known as membrane biogenesis. (‘Biogenesis’ means ‘generation of a substance by living matter).

The structure, characteristics, and function of the endoplasmic reticulum (ER) in the cell are:

Structure and function of the endoplasmic reticulum (ER)

b. Ribosomes

The ribosomes are numerous small granules either scattered freely in the cytoplasm or attached to the membranes of the endoplasmic reticulum. These are the single-walled dense, spherical bodies composed mainly of RNA. The most essential function of the ribosome is protein synthesis. Therefore, we also call them ‘factories’ or ‘sites’ for the synthesis of proteins.

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c. Mitochondria

Mitochondria are the sites where cellular respiration occurs to release energy. Therefore, we can call mitochondria as “powerhouse of the cell or seat of cellular respiration”. The mitochondria are spherical or rod-shaped, or thread-like bodies. Mitochondria have ribosomes and DNA containing several genes. Due to this, mitochondria can even survive without a cell, thus it is a semi-autonomous organelles.

The structure and function of the mitochondria in the cell are:

Structure and Function of mitochondria in the cell

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d. Golgi Apparatus

The Golgi apparatus acts as the delivery system of the cell. They occur in the form of granules, filaments, or rods that originate from the endoplasmic reticulum. These are tiny vesicles of different shapes arranged in parallel stacks  (cisterns) located near the nucleus. The main function of the Golgi apparatus is the secretion of the cell, including enzymes, hormones, etc.

Structure and Function of the Golgi Apparatus in Cell

e. Lysosomes

Lysosomes are small vesicles of different shapes that bud off from the Golgi bodies. They contain 40 different types of enzymes. They help to keep the cell clean by digesting any foreign material as well as worn-out cell organelles. Lysosomes can do this because they contain powerful digestive enzymes (acid hydrolases) capable of breaking down all organic material. The enzymes are synthesized by the rough endoplasmic reticulum (RER). During the disturbance in cellular metabolism, for example, when the cell gets old or damaged, lysosomes may burst and enzymes are released to digest their cell. Hence, these are called “suicide bags”.

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f. Centrosomes and Centrioles

A centrosome is present in animal cells only. It is located in a clear area of the cytoplasm close to the nucleus. Centrosomes consist of two barrel-shaped clusters of microfilaments, called “centrioles”. These two centrioles are arranged at right angles to each other. It develops spindle fibers during cell division, both in mitosis and meiosis. There are no centrosomes and centrioles in plant cells.

Structure of Centrosome and Centrioles

The structure of the Centrosome

• Centrosomes contain two centrioles arranged at right angles to each other.
• Centrioles are short, barrel-shaped bundles of microfilaments.
• Its microfilaments form a radiating star (aster) like structure during cell division.

The function of the Centrosome in the cell

• Initiate and regulate cell division.
• Forms spindle fibers, with the help of asters.

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g. Plastids

Plastids are present only in plant cells. The function of plastids in the cell is to manufacture and store food in plants. They occur in different shapes – oval, spherical, and disc-shaped.

Structure of Plastids

Depending upon the color, the plastids are of three types – leucoplasts, chromoplasts, and chloroplasts.

1. Leucoplasts are colorless plastids. They have no pigments. They store starch. The cells of potatoes have lots of leucoplasts in them.
2. Chromoplasts are plastids of various colors – yellow, orange, and red. They are mostly present in the petals of flowers and fruits. The coloring substances (pigments) associated with them are xanthophyll (yellow) and carotene (orange-red).
3. Chloroplasts impart a green color to a plant. They have green pigments called chlorophyll. Chloroplasts are abundant in parts exposed to light, for example, leaves. They also have other pigments such as orange and yellow. However, the chlorophyll present in large amounts masks these pigments. Their function is to trap solar energy and absorb carbon dioxide for the manufacture of starch and sugar during photosynthesis. Chloroplasts contain DNA and have the capacity to divide.

Back to >>>>Structure and Function of the Cell

NON-LIVING PARTS OF THE GENERALIZED CELL

a. Granules

Granules are small particles in the cytoplasm that store food particles, such as starch, glycogen, and fats.

b. Vacuoles

Vacuoles are clear spaces in the cytoplasm. They are filled with water and various substances in the solution state. A single membrane called ‘Tonoplast’ bound these bubble-like sacs. In plant cells, the vacuoles are usually quite large, and the liquid that they contain is called cell sap.  The cell sap contains proteins, minerals, organic acids, etc. Vacuoles provide turgidity and rigidity to the cell. An animal cell does not have such prominent vacuoles, and vacuoles are fewer.

Back to >>>>Structure and Function of the Cell

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Discover the diversity of plants! Learn about Kingdom Plantae with clear examples, detailed classification systems (thallophytes to angiosperms), and essential characteristics. Perfect for students and science enthusiasts!

At Selftution.com, we’re committed to being the best educational website – making complex biology simple, accurate, and easy to understand.

So, let’s begin.

The classification of the plant kingdom, or the Kingdom Plantae, based on characteristics, along with examples, is as follows:

• Primary classification
  • Flowering plants – Plants that bear flowers
    • Angiosperms – mango, peas, apple, sugarcane, and grass.
    • Gymnosperms – pine, fir, cedar, and spruce trees
  • Non-flowering plants – Plants that do not bear flowers
    • Algae – Chlamydomonas and Spirogyra
    • Bryophyta – mosses
    • Pteridophyta – ferns
• Classification and examples of the plant kingdom based on habit
  • Herbs – Mustard, pea, paddy, and ladyfinger
  • Shrubs – China rose, and oleander
  • Trees – mango, cedar, and spruce
• Classification and examples of the kingdom Plantae based on lifecycle
  • Annual – Wheat, peas, and rice
  • Biennial – Reddish, carrot, and turnip
  • Perennial – Guava, palm, and coconut.
• Classification and examples of the plant kingdom based on the mode of nutrition
  • Autotrophs – plants that prepare their food – Most green-colored plants
  • Heterotrophs – A Plant that does not prepare food
    • Parasites – Cuscuta, and Viscum
    • Saprophytes – yeast and fungi.
• Classification and examples of the kingdom Plantae based on habitat
  • Mesophytes – mango and apple
  • Hydrophytes – Lotus, and water lilies
  • Xerophytes – Cactus

Click here to download – Classification of the Kingdom Plantae with characteristics and examples

Topics Covered:

• Introduction
• Primary classification and examples of the plant kingdom
  1. Non-flowering Plants
  2. Flowering Plants
• Other classifications and examples of the Kingdom Plantae
  1. Habit
  2. Life Cycle
  3. Mode of Nutrition
  4. Habitat

INTRODUCTION

The Plant Kingdom, or the Kingdom Planta,e comprises 17% of the total species studied by mankind to date. In number, it comes out to be nearly 2,21,000. Isn’t it large? Interestingly, this number is only 15% of the total species of plants present on the planet Earth.

Plants exhibit great diversity in characteristics. Some of them are microscopic and invisible to the eyes, and then there are others as huge as a banyan tree. Due to their large number and varying characteristics, it is impossible to study them individually. So, to help, all members of the plant kingdom with similar characteristics are clubbed together to form groups. We call this process the classification of the plant kingdom or the kingdom Plantae. In this post, we will learn about the different bases used for classification in the Kingdom Plantae, along with examples and characteristics of each group. For classification of the animal kingdom, click here.

Click here to download – Classification of the Kingdom Plantae with characteristics and examples

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PRIMARY CLASSIFICATION OF THE PLANT KINGDOM WITH EXAMPLES

Plants are useful to all of us. They provide us with useful products, for example – (i) cereals like wheat and, rice (ii) fruits like bananas, apples, and mangoes (iii) vegetables like potato, spinach, beans, and tomato (iv) sugar, tea, coffee (v) wood for our home (vi) medicines and numbers of other items. How have these large numbers of products become available to us? It is because there is a great variety of plant life on the planet Earth. They differ in habitat, types of plants, size, habit, duration of life cycles, mode of nutrition, and various other characteristics. Many plants have also developed special organs for performing special functions, like climbing and protection.

We can classify the Kingdom Plantae in numerous ways; however, the most common one is the division into a group of non-flowering and flowering plants.

• Non-flowering plants do not bear flowers. Examples are Chlamydomonas, Spirogyra, mosses, and ferns.
• Flowering plants, as the name suggests, bear flowers. Examples are mango, rose, sunflower, sugarcane, grass, pine, fir, and cedar.

Classification and examples of the Kingdom Plantae or the Plant Kingdom – Flowering and nonflowering plants.

Due to the varying characteristics of flowering plants, they are further classified based on habit, duration of the life cycle, mode of nutrition, and habitat.

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1.0 NON-FLOWERING PLANTS

Nonflowering plants have three classifications: Algae, Bryophyta, and Pteridophyta

ALGAE

Filamentous Algae

Algae in a pond

Algae are aquatic in habitat and found in both marine and freshwater environments. They are usually green and have chlorophyll. Mostly, they are found on the surface of the ponds where they get ample sunlight for preparing food. Algae may be single-celled or multicelled. Examples are – Chlamydomonas single-celled alga, and Spirogyra, which is a multi-celled filament-shaped alga commonly found in ponds.

Click here to download – Classification of the Kingdom Plantae with characteristics and examples

BRYOPHYTA (MOSSES)

The green layer of mosses

Bryophyta, or mosses, grow as green, velvety layers in moist and shady places such as damp soil, on the bark of trees, and damp walls. These plants have peculiar characteristics in that they have stems and leaves, but no roots. Instead, they have threadlike structures called rhizoids that stick to the surface and absorb water and minerals.

PTERIDOPHYTES (FERNS)

Ferns – Plants used for decoration

Pteridophytes, or ferns, are grown in most gardens for their beautiful leaves. They bear well-formed leaves, stems, and roots, but do not produce flowers and seeds. Their leaves produce small, rounded bodies on their undersurface. These bodies contain tiny spores, which are capable of producing plants. When leaves fall or these spores get scattered and reach the soil, they produce new plants. It is important to note that spores are not seeds.

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Click here to download – Classification of the Kingdom Plantae with characteristics and examples

2.0 FLOWERING PLANTS

Flowering plants are also known as seed-bearing plants. They further have two classifications – Gymnosperms and Angiosperms.

GYMNOSPERMS

The Gymnosperms are a group of plants that bear seeds, but no fruits. Their seeds are thin and naked, not enclosed in fruits (‘gymno’ means ‘naked’; sperm means ‘seed’). Most gymnosperms are evergreen, i.e., they do not shed all their leaves at one time. Some examples are pine, fir, cedar, and spruce trees that grow in hilly areas. Pine and fir are usually big trees. They do not bear true flowers, but they carry seeds inside the cones.

Pine Trees

Seeds bearing the cone of a pine tree

ANGIOSPERMS

Angiosperms are a group of plants that bear flowers, fruits, and seeds (‘angios‘ means ‘case‘, referring to the fruit;  ‘sperm‘ means ‘seed‘). One of the most important characteristics of angiosperms is that their seeds are enclosed in a fruit. Some common examples are mango, peas, apples, sugarcane, grass, etc. In angiosperms, the seeds develop within the female part of the flower, called the ovary. The ovary grows into fruit, and ovules inside the ovary grow to form seeds.

Apple tree is an example of an Angiosperm

Apple seeds are enclosed inside a fruit

Think of the plants such as sugar cane and mint, or even the lawn grass. Do they bear flowers? They are flowering plants indeed. If you observe the lawn grass, you can, at times, see tiny flowers on it. Similarly, sugarcane and mint bear flowers. Since these plants are cut for human use before they mature to produce flowers, we do not see their leaves.

Sugarcane Flower

Monocotyledons and Dicotyledons

Angiosperms can be further classified into two groups – monocotyledons and dicotyledons. If you observe a germinating gram seed, you will notice two thick “seed-leaves“. These leaves store food and form the bulk of the seed. Similarly, when you eat peeled groundnuts, you find two thick bits in a single seed. We call these bits cotyledons. Cotyledons store food required by the seedlings during germination. Monocotyledons are plants that bear seeds with a single cotyledon or one seed leaf in their seeds. For example, maize and carrots. Dicotyledons are plants that bear seeds with two cotyledons or two seed leaves in their seeds. For example, a gram and a pea.

Maize seed – An example of a monocotyledon seed

Kidney Bean Seed – Split open to show both cotyledons of the seed

Kidney Bean Seeds – An example of a dicotyledon seed

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CLASSIFICATION OF PLANT KINGDOM BASED ON CHARACTERISTIC FEATURES

Other than the classification of the kingdom Plantae based on flowering and non-flowering plants. The Plant kingdom classification is also based on characteristic features like habit, types of plants, size, duration of life cycles, mode of nutrition, and habitat.

Click here to download – Classification of the Kingdom Plantae with characteristics and examples

1.0 Classification and Example of Kingdom Plantae Based on Habit

Under this classification, flowering plants are divided into three groups based on their habits or physical features – herbs, shrubs, and trees.

A Classification of Plants based on Habit

HERBS

Herbs are small plants with soft stems. They do not grow more than three to four feet in height. Examples – Mustard, sunflower, pea, coriander, paddy, and ladyfinger.

SHRUBS

Shrubs are medium-sized plants with hard and woody stems. Many branches are seen rising just above the ground. Examples – China-rose, rose, and oleander.

TREES

Trees are tall plants with hard and woody stems. They have the main trunk from which branches and leaves arise. Trees generally survive for several years. Examples – mango, coconut, neem, and banyan.

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Click here to download – Classification of the Kingdom Plantae with characteristics and examples

2.0 PLANT KINGDOM CLASSIFICATION AND EXAMPLES BASED ON LIFE CYCLE

Based on the life cycle, flowering plants can be classified as annual, biennial, and perennial plants.

ANNUAL PLANTS

These plants complete their life cycle in one year from seed to flower. They grow from seeds, produce flowers, seeds, and die in the same year. Examples – Wheat, peas, rice, tomato, pulses, etc.

BIENNIAL PLANTS

These plants have a two-year life cycle. In the first year, they produce leaves and roots. In the winter, the leaves die. The root survives, and new leaves, flowers, and seeds are produced in the second year. The plant then dies. Examples – radish, carrot, beetroot, and turnip.

PERENNIAL PLANTS

These plants live for many years and produce roots that store food. Food is also sometimes stored in other parts of the plant. The root survives the winter,r and the plant produces leaves, flowers, and seeds year after year. Examples – Mango, guava, palm, and coconut.

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3.0 CLASSIFICATION AND EXAMPLES OF KINGDOM PLANTAE BASED ON MODE OF NUTRITION

Like animals, plants need food. Based on their nutrition, the plants are classified into two groups – autotrophs and heterotrophs.

AUTOTROPHS

As discussed in the post, classification of living things, autotrophs are those plants that prepare their food. These plants are green-colored due to the presence of green pigment, chlorophyll. With the help of chlorophyll in the presence of sunlight, water, and carbon dioxide, they prepare food by the process of photosynthesis. Examples – Most green-colored plants.

HETEROTROPHS

Heterotrophs are non-green plants and are dependent on other plants or animals for obtaining food. They are of two types, depending upon the source from which they obtain their nutrition – parasites and saprophytes.

• Saprophytes feed on the dead and decomposed bodies of plants and animals. Examples are yeast, mushrooms, and fungi.
• Parasites are those plants that obtain their food from other living organisms without killing them. Examples – Cuscuta, Viscum, and Orobanche.

For a better understanding of parasitic plants, go through a fascinating YouTube video from Twig Education

Click here to download – Classification of the Kingdom Plantae with characteristics and examples

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4.0 PLANT KINGDOM CLASSIFICATION AND EXAMPLES BASED ON HABITAT

Plants are also classified based on their natural place of occurrence (habitat) as mesophytes, hydrophytes, and xerophytes.

MESOPHYTES

Mesophytes are plants living on land with sufficient water. Examples – herbs, trees (mango, apple).

HYDROPHYTES

Hydrophytes are plants that live in water. Examples – lotus and water lily.

XEROPHYTES

Xerophytes are plants that live on land with a scarcity of water, as in a desert. Examples – cactus

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Master cell biology with clear comparisons, labeled diagrams, and easy-to-understand explanations. Welcome to Selftution.com – simplifying science for effective learning!”

So, let’s begin.

The Structure of a Generalized Cell helps us understand how all living things function.

Every living organism, whether a plant or an animal, is made up of tiny building blocks called cells.

These cells have different parts, each performing a special job to keep the cell alive and working properly.

Both plant and animal cells share many common structures, such as the cell membrane, cytoplasm, nucleus, mitochondria, and ribosomes.

However, plant cells have some additional parts, like the cell wall and chloroplasts, which help them make their food.

In this blog, we will explore the structure of a generalized cell, its main organelles, and how plant and animal cells differ.

Understanding these differences will help us learn how living things grow, develop, and survive.

For a video explanation…click here

Definition of Generalized Cell

The generalized cell is the basic representation of the cell showing all parts and organelles which can be present in any specialized cell. It is a hypothetical cell for a quick understanding of the basic structure and function of the cell and its organelles.

The structure of generalized cells differs for plants and animals due to the presence or absence of certain parts or organelles. To know more about the difference in the structure of generalized plant and animal cells, click here.

Structure of a Generalized Animal Cell

Structure of a Generalized Plant Cell

All generalized plants and animal cells consist of living and non-living parts.

STRUCTURE OF THE LIVING PART OF A CELL

The living part of the cell includes the cell or plasma membrane, the cytoplasm, and the nucleus. All three together are known as protoplasm. The non-living parts of the cell are granules and vacuoles.

1. Cell Membrane or Plasma Membrane

The cell membrane is a very thin skin covering the cell. The cell membrane protects the cell and provides shape to it. It is made up of lipoprotein. There are very tiny holes in the cell or plasma membrane. It allows materials to enter and leave the cell through these tiny pores or openings. However, its permeability is selective. It means it allows certain substances to pass through it and prevents others.

The structure and function of a cell or the plasma membrane of a generalized cell are:

Structure and Function of the Cell or Plasma Membrane

Cell Wall: The cell wall is an extra covering that surrounds the cell membrane of a plant cell. It is made of stiff, non-living material called cellulose. The cell wall provides rigidity and protection to the cell. Unlike the cell membrane, it is freely permeable and allows all substances in solution form to pass through it. Animal cells do not have a cell wall.

The structure and function of a cell wall in a generalized plant cell are:

Structure and Function of the Cell Wall in a Generalized Cell

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2. Cytoplasm

The cytoplasm is a jelly-like, semi-liquid structure occupying most of the inside of the cell. It occupies the space between the cell membrane and the nucleus. Under a microscope, it appears to be colorless, partly transparent, and somewhat watery. It is a living part of the cell, and all the life functions take place in the cytoplasm. The living cytoplasm is always in a state of motion.

The cytoplasm contains many important tiny structures called organelles, which perform various life functions. Organelle means ‘the little organs’. Organelles have a definite structure and a definite function in the cell and have the same status in the generalized cell as the organs have in the body of an animal or a plant. Apart from the nucleus, various other organelles present in the cytoplasm of a generalized cell are the endoplasmic reticulum, Golgi apparatus, mitochondria, ribosomes, lysosomes, centrosome, vacuole, and plastids.

The structure and function of the cytoplasm of a generalized cell are:

Structure and Function of Cytoplasm in an Animal or Plant Cell

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3. Nucleus – The Control Center of the Cell

The nucleus is a spherical body present in the cell. This structure is the control center of the cell, and its function is to regulate and coordinate the various life processes of the cell. Most cells have only one nucleus, but some cells, like those of muscles, have more than one nucleus.

The structure and function of the nucleus of a generalized cell are:

Structure and Function of the Nucleus of the Cell

The nucleus comprises four parts – nuclear membrane, nuclear sap or nucleoplasm, nucleolus or nucleoli, and chromatin fibers.

Nuclear membrane – It is the delicate outermost covering layer of the nucleus. It separates the nucleus from the cytoplasm. The nuclear membrane, like the cell membrane, has tiny holes in it that allow the exchange of substances between the nucleus and the cytoplasm.

Nucleoplasm – It is the jelly-like fluid inside the nucleus. Chromatin fibers and nucleoli are embedded in the nucleoplasm.

Chromatin fibers – A network of threadlike structures called the chromatin network is present in the nucleoplasm. It consists of DNA (deoxyribonucleic acid) and proteins. At the time of cell division, the chromatin fibers develop into thick and ribbon-like or rod-like structures called chromosomes. These chromosomes play an important role in carrying the genetic characters from the parents to the offspring.

Nucleolus or nucleoli – It is a dense, dark, granular structure without a membrane.  It consists of RNA (ribonucleic acid) and proteins. It is the site of ribosome formation; thus, we can call it the factory of ribosomes.

NON-LIVING PARTS OF A CELL

a. Granules

Granules are small particles in the cytoplasm that store food particles, such as starch, glycogen, and fats.

b. Vacuoles

Vacuoles are clear spaces in the cytoplasm. They are filled with water and various substances in the solution state. A single membrane called ‘Tonoplast’ bound these bubble-like sacs. In plant cells, the vacuoles are usually quite large, and the liquid that they contain is called cell sap.  The cell sap contains proteins, minerals, organic acids, etc. Vacuoles provide turgidity and rigidity to the cell. An animal cell does not have such prominent vacuoles, and vacuoles are also fewer in number.

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Master the concept of tissues – explore their definition, major types (epithelial, connective, muscular, nervous), and practical examples with easy-to-follow explanations and diagrams.

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Living things are made of tiny, living compartments called cells. Cells perform life functions, but alone, their impact is minimal in plants and animals.

To work efficiently, many similar cells join together, forming tissues. Tissues are specialized groups of cells that perform specific functions vital for life processes.

In animals and plants, tissues provide structure, enable movement, and carry out essential activities like transport, growth, and repair. Each type of tissue has a unique role.

Understanding tissues helps us explore how life functions at a cellular level. From muscle in animals to xylem in plants, their importance is undeniable.

What are Tissues?

All multicellular organisms (animals or plants) start their life as a single cell called a zygote (fertilized egg).

Representation of Tissue

This zygote divides repeatedly to produce billions of cells of various kinds. The cells formed have different shapes and structures based on the functions performed. Some of these cells make skin, some muscles, some others form bones, and still others form blood. A group of cells, which are similar in structure and perform a particular function, form a tissue. For example, the human body has epithelial tissue covering the skin, the cells constituting muscles are contractile and therefore constitute muscle tissue that brings about movement. In a plant, the cells that help in conducting food and water form phloem and xylem tissues.

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Definition of a Tissue

A tissue is a group of similar cells performing a specific function.

Relationship Between Tissue, Organ, Organ System, and Organism

Relationship between a cell, tissue, organ, organ system, and organism

• Different tissues together contributing to some specific function inside the body constitute an organ. For example, the tongue is an organ comprised of three types of cells. These are epithelial cells for protection, nerve cells for sensing taste, muscle cells for movement, etc.
• Many organs acting together to perform a specific life process form an organ system. For example, the digestive system comprises organs like the tongue, esophagus, stomach, liver, intestines, etc.
• Organ systems together constitute the organism. For example, the digestive system, circulatory system, skeletal system, etc., constitute the human.

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Types of Plant Tissues

Plant tissues are basically of two types – meristematic and permanent.

1. Meristematic Tissue:

These are made of actively dividing cells. Their only function is to produce more cells, leading to the growth of the plant body. They are found at all growing points of a plant, like the tips of roots, stems, and branches, where growth in length occurs. The growth of the thickness of the stem is also due to meristematic tissue. To learn more about meristematic tissues, click here.

2. Permanent Tissue:

These are groups of cells in which growth has either stopped completely or for the time being. They form the bulk of the plant body. Cells of permanent tissue do not divide. They become specialized to perform a specific function and remain the same throughout their life. There are two further types:

• Simple permanent tissues (provide support and protection), and
• Complex permanent tissues (conduct nutrients and water).

Simple permanent tissues provide protection and support to the plant. The tissues that provide protection are called protective tissues, whereas those that provide support are called supporting tissues. Supporting tissues are of three further types – parenchyma, collenchyma, and sclerenchyma.

Complex permanent tissues or conducting tissues provide a passage for water and minerals to move up and down the plant. These are of two types – xylem and phloem.

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Types of Animal Tissues

The animal tissues are of four types: epithelial, connective, muscular, and nervous.

1. Epithelial Tissue

This tissue forms a protective layer of cells. It covers the surface of the body and forms the lining of various body cavities and internal organs.  Based on the shape and functions, epithelial tissues are of four types: squamous, cuboidal, columnar, and ciliated epithelium.

2. Connective Tissue

As the name suggests, connective tissue connects various other tissues and organs. They also provide support to different organs to keep them in a proper position. They are of three types: supporting, fibrous, and fluid connective tissues.

• Supporting connective tissues consists of cartilage and bones, which provide support and a structural framework.
• Fibrous connective tissue serves to pack and bind most of the organs. There are four types: adipose, areolar, ligament, and tendons.
• Fluid connective tissue consists of blood and lymph and serves the purpose of transporting glucose, amino acids, oxygen, etc.

3. Muscular Tissues

They form the muscles of the body. The muscles can contract and relax. Thus, they help the body in all its movements and locomotion. Three distinct kinds of muscles are striated, unstriated, and cardiac.

4. Nervous Tissues

They constitute the nervous system. It is concerned with the perception and responses of animals. This tissue comprises elongated cells called neurons.

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Conclusion

In conclusion, the organization of cells into specialized groups highlights the efficiency and complexity of living organisms. These cell groups perform essential tasks that support life, from movement and growth to transport and repair. By understanding the types and functions of these structures, we gain deeper insight into how plants and animals thrive. Whether it’s the transport of nutrients in plants or the coordination of movements in animals, these cellular formations play an integral role. Exploring them reveals how life is both interconnected and beautifully orchestrated, showcasing the brilliance of nature’s design.

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Discover the essential differences between living and non-living things with clear explanations, vivid examples, and interactive diagrams – only at Selftution.com, the best educational website for simple, effective learning.

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There are millions of things in this World, some alive and some not. How do we distinguish between what’s alive and what’s not?

In this post, we’ll delve into the characteristics of living and non-living things to help us answer this question.

We’ll also explore the similarities shared by both living and non-living entities.

LIVING AND NON-LIVING THINGS

Living things have distinct traits that differentiate them from non-living objects. One such trait is their ability to grow, increasing in size and complexity over time.

Additionally, living organisms can reproduce, creating new individuals of their kind.

They also adapt to environmental changes to ensure survival and well-being. These traits collectively define what it means to be alive.

In contrast, non-living things cannot grow, reproduce, or respond to their surroundings. They do not exhibit the dynamic processes that living organisms undergo.

However, despite these differences, there are also similarities between living and non-living things. Both types of entities occupy space and have mass, and they interact with each other and their environment in various ways.

By comprehending these distinctions and commonalities, we gain a deeper understanding of the characteristics of living and non-living things.

Before we proceed further, here are some examples of living and non-living things:

Examples of Living and non-living things

In the picture, if we look at a plant and a book, we will notice that these two objects differ in some respects. A book can’t move by itself, eat, grow, or make more books like itself. But a plant can do all these things. Its stem grows up, it can get its food, and it makes more plants of the same kind. So here, we identify a few characteristics that help us to differentiate between living and non-living things.

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COMMON CHARACTERISTICS OF LIVING AND NON-LIVING THINGS

From the above picture, we can identify the following two common characteristics of living and nonliving things:

Cells are the basic structural units of living things. They do not exist in nonliving things

1. All living things are made of stuff called matter. It possesses mass and occupies space.
2. Both living and nonliving things have structural units. Living things have small parts called cells, and nonliving things have tiny parts called molecules.

Onion rings showing cells

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DIFFERENCE BETWEEN LIVING AND NON-LIVING THINGS

Defining “life” isn’t easy; it’s unique and special. Instead of pinpointing an exact definition, we focus on the characteristics that set living things apart from non-living ones. While non-living objects may display some of these traits, they don’t possess all of them. For instance, a machine can move, but it can’t grow or make another machine like itself.

CHARACTERISTICS THAT DIFFERENTIATE LIVING AND NON-LIVING THINGS

Nine characteristics distinguish living things from non-living ones, which are as follows:

Nine characteristics of living things that differentiate them from non-living things

1. CELLULAR ORGANIZATION

Amoeba

Among all the characteristics that define life, cellular organization stands out as the most significant feature distinguishing living from non-living things. Every living organism, whether it’s a plant or an animal, is composed of microscopic units known as cells. These cells serve as the fundamental building blocks of life, providing structure and carrying out essential functions. In contrast, non-living objects lack this intricate cellular structure. Some living organisms, such as amoebas, euglenas, and bacteria, consist of a single cell, earning them the title of unicellular organisms. However, the majority of living beings are multicellular, comprising billions of cells working together harmoniously. Examples of multicellular organisms range from fruits like mangoes to creatures like butterflies and even majestic mammals such as elephants, tigers, and cats.

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2. NUTRITION

Living beings, like animals and plants, need nutrition, which is the process of taking in food. This food supplies them with energy for their activities and aids in their growth and repair

Animals acquire ready-to-consume food, such as milk, bread, meat, eggs, vegetables, and fruits, to fulfill their nutritional requirements and maintain their energy levels. In contrast, plants manufacture food through photosynthesis, utilizing carbon dioxide, water, and nutrients from the soil. This process enables them to grow and sustain independently, without dependence on external sources.

Therefore, the ability to obtain and utilize nutrition is a key characteristic that distinguishes living organisms from non-living things. Living things actively seek out or produce their food to sustain life processes, while nonliving things do not engage in such activities

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Proper nutrition is Important for Growth

3. GROWTH

Consider the transformation of a baby into an adult or the journey of a seed evolving into a plant. This process is called growth, and it’s permanent and irreversible. All living entities, plants or animals, undergo this fundamental aspect of life. However, how growth unfolds can vary between different organisms.

In contrast, nonliving objects lack the inherent ability to undergo growth. Any apparent expansion or development in non-living entities is attributed to external influences. For instance, the construction of a house may involve an increase in size, but this growth is facilitated solely by external factors such as human labor and construction materials. Should these external stimuli cease, the non-living entity would remain static and devoid of any further expansion

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4. EXCRETION

Excretion is the process of removal of waste material from the body. The removal of waste material from the body is crucial for maintaining the health and proper functioning of living organisms. Accumulation of waste material within the body can be detrimental to all living beings. Consequently, living organisms have evolved mechanisms to eliminate waste materials. In animals, waste materials are expelled from the body in various forms, including urine, sweat, and carbon dioxide. These byproducts of metabolic processes are actively removed to prevent internal imbalances and toxicity.

Plants, while ridding themselves of waste gases and excess water, utilize a different mechanism. Through small pores called stomata located on the surface of their leaves, plants release waste gases such as carbon dioxide and water vapor. This process ensures the proper exchange of gases necessary for photosynthesis and respiration, thereby maintaining the health and vitality of the plant.

In contrast, non-living entities do not generate waste material through metabolic processes and therefore do not require mechanisms for waste removal.

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5. REPRODUCTION

If someone were to ask you about one of the most distinctive features of life that sets living things apart from non-living things, your answer would likely be reproduction. Reproduction is the remarkable ability of all living organisms to produce offspring of their kind. For instance, a hen lays eggs that hatch into chicks, which then mature into hens or roosters. Similarly, a dog gives birth to puppies that grow into adult dogs or bitches. Likewise, a mango tree bears fruits containing seeds that germinate into new mango trees. However, it’s impossible to replicate this reproductive process with inanimate objects like tables or chairs.

The life cycle of a Hen

Hen with her newborn chicks

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6. RESPIRATION

Respiration, a fundamental process for both animals and plants, entails the intake of oxygen from the surrounding air and the release of carbon dioxide as a byproduct. This exchange of gases is vital for sustaining life. Animals and plants alike harness oxygen to break down the nutrients obtained from food or photosynthesis, respectively, converting them into a form of energy known as adenosine triphosphate (ATP). This energy is the currency of life, fueling cellular activities such as growth, movement, reproduction, and maintenance of internal functions. Moreover, respiration is not solely confined to oxygen uptake and carbon dioxide release; it encompasses a series of complex biochemical reactions occurring within cells, involving various enzymes and metabolic pathways. Thus, respiration serves as the cornerstone of energy production and utilization in living organisms, facilitating their survival and enabling them to thrive in diverse environments.

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7. MOVEMENT

Living things exhibit movement. Every day, you witness animals, birds, insects, and humans moving from one place to another. This form of movement is termed locomotion. Animals move for two primary reasons: to seek out food and to evade predators.

Some animals, like the hydra and sponge, do not move around to search for food. They remain fixed to the ground and capture food using elongated structures called tentacles. Most plants are rooted in the soil and cannot perform locomotion, but they do exhibit movement. The stem moves upward and sideways in plants to optimize leaf exposure to sunlight. Additionally, the roots of a plant extend downward and sideways in the soil, providing structural support and foraging for nutrients and water.

For better visualization of movement by plants, check out this time-lapse video by Gardening at 58 North

Some nonliving things also exhibit movement; for instance, a car or a bus moves, and the hands of a clock tick forward. But is the movement of these things similar to that of living beings? The answer is ‘No.’ Cars, buses, and clock hands move due to the chemical energy supplied by petrol, diesel, or batteries, which are external factors.

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8. RESPONSE TO CHANGE

Anything that produces a response in an organism is called a stimulus.Living things demonstrate responsiveness to changes in their environment, a vital characteristic that distinguishes them from nonliving entities. For instance, in cold weather, we instinctively don woolen clothes to keep warm. If we accidentally touch something hot, our immediate response is to withdraw our hands to avoid injury. Similarly, during drought conditions, plant roots extend deeper into the soil in search of water, showcasing their adaptive behavior to ensure survival.

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9. LIFE CYCLE

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Living things embark on a life cycle, beginning as a single cell and progressing through stages of growth, reproduction, and eventual death. This cycle spans a varied timeframe, ranging from mere hours to several centuries. This duration, known as the lifespan, varies greatly among different organisms. Bacteria, for instance, complete their life cycle within minutes, showcasing rapid turnover. In contrast, creatures like tortoises boast extensive lifespans, enduring for up to 120-150 years. Regardless of the length, all organisms navigate through this cycle, with each stage contributing to the intricate tapestry of life on Earth. Through growth, reproduction, and eventual demise, living beings perpetuate their existence, shaping the rich diversity and complexity of the natural world.

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CHARACTERISTICS OF NON-LIVING THINGS

As discussed above, the important characteristics of non-living things can be summarized below:

1. All nonliving things consist of microscopic structures called atoms.
2. They do not require food for energy to perform various activities.
3. Nonliving things do not experience growth in size; any growth observed is due to external factors.
4. Nonliving things do not engage in excretion.
5. They do not reproduce or give birth to offspring of their kind.
6. Nonliving things cannot move autonomously. However, certain nonliving objects, such as cars and buses, can move due to chemical energy provided by sources such as petrol, diesel, or batteries, which are external factors.
7. Nonliving things do not engage in respiration or respond to external stimuli.
8. Lastly, nonliving things do not undergo a life cycle.

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DIFFERENCE BETWEEN NON-LIVING AND DEAD

We can call only those things dead that once lived and followed the life cycle. For example, we can call a block of wood and a leather dead because they come from organisms that once lived. But a chair made of wood or a shoe made of leather is nonliving. Stone, water, and a car are nonliving because they never show any of the characteristics of life or living things. So, to summarize, a dead thing is one that once lived and showed one or more characteristics of life, whereas nonliving things are those that were never alive. The difference between nonliving and dead in tabular form is as below:

Difference between non-living and dead

END…..Characteristics of living and nonliving things

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Types of Permanent Tissues

New cells form when the meristematic plant tissues divide. These newly formed cells elongate, mature, and get differentiated into various types of permanent tissues. Permanent plant tissues do not divide further. Permanent plant tissue is the group of cells in which growth has either stopped completely or for the time being.

SIMPLE PERMANENT TISSUES

Simple permanent tissues are virtually present in every part of the plant. They consist of only one type of cell. All cells that make up the simple permanent tissue are similar in structure and perform the same function. The major functions of the simple permanent tissue are to provide support and protection to the plant. Apart from these, they are also responsible for: tissue repair, secretion, food storage, and photosynthesis.

According to the function performed simple permanent plant tissues are of two types:

1. Protective Tissues, and
2. Supportive Tissues.

Protective Plant Tissues

These tissues consist of cells with thick walls. They are living cells present on the surface of leaves, roots, and stems. For example,

• The epidermis of leaves, which secretes a waxy waterproof substance, and
• Cork cells in the barks contain another strong waterproof material.

Supportive Tissues

As the name suggests, the main function of the supporting tissues is to provide support to various parts of a plant. They may consist of living or dead cells. Based on varying cell properties supportive simple permanent tissues are of several types. The three most important ones are – parenchyma, collenchyma, and sclerenchyma.

Parenchyma and collenchyma consist of living cells, whereas sclerenchyma is made up of cells that have become dead. Parenchyma mainly acts as a packing tissue. They provide mechanical strength and also store food. Collenchyma tissue provides flexibility as well as mechanical support to plants. Last but not least, sclerenchyma provides rigidity to the plant body.

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COMPLEX PERMANENT TISSUES

Complex permanent plant tissues are present in the vascular region of the plant. They help in the conduction of nutrients and water throughout the plant body. Complex permanent plant tissue consists of a group of multiple types of cells that have a common origin but perform different functions. It consists of both living and dead cells which coordinate together to perform the same specialized functions in the plant body. Based on their structure and function performed, complex permanent tissues are of two types – xylem and phloem.

Xylem

The xylem tissue is responsible for the conduction of water and minerals from the roots to the leaves and stems. It also provides support to the plants. It has four elements. They are tracheids, vessels, xylem parenchyma, and xylem fibers.

Phloem 

This complex permanent tissue helps in the conduction of food that is prepared by photosynthesis in the leaves to various parts of the plant. Phloem consists of four elements. They are sieve tubes, companion cells, phloem fibers, and phloem parenchyma.

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DIFFERENCE BETWEEN SIMPLE AND COMPLEX PERMANENT TISSUES

Difference between Simple and Complex Permanent Plant Tissue

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Explore the fascinating world of meristematic plant tissues – the growth engines of plants! Learn about apical, lateral, and intercalary meristems, their functions, and real-life examples in this detailed guide.

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We derive the word ‘meristematic’ or ‘meristem’ from the Greek word ‘meristos’, which means ‘divide’. Therefore, meristematic plant tissues are made of actively dividing cells.

The cells that form meristematic tissue can multiply and produce new cells. Their function is to produce more cells, leading to the growth of the plant body.

A meristem is the part of the plant body where these cells exist.

We can find meristematic tissues at all growing points of a plant, like the tips of roots, stems, and branches, where growth in length occurs.

Likewise, they also exist between the bark and the wood of trees, leading to growth in the diameter of the stem.

The main characteristics of these tissues are tabulated below:

Characteristics of Meristematic Plant Tissues

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TYPES OF MERISTEMATIC PLANT TISSUES

We classify meristematic tissue based on origin, location, and function.

Types of meristematic plant tissues or meristems based on origin, location, and function

Meristematic Plant Tissues Based on Origin

Based on origin, meristematic tissues are of three types: the promeristem, the primary meristem, and the secondary meristem.

Promeristem:

It is a group of young meristematic cells that originates from the embryo. As the promeristem originates from an embryo, therefore, it is also called the primordial meristem. They are mostly present at the shoot and root tip of a plant from which the other meristems arise. Promeristem forms the primary meristem in plants.

Primary Meristem:

It is a type of meristematic tissue that is responsible for primary growth, i.e., growth in length. The growth in length originates from the promeristem and produces cells that become permanent tissues. For example, ground and primary vascular tissues. An example of a primary meristem is the apical and ground meristem.

Secondary Meristem:

It is the meristematic tissues that originate from the permanent tissues. The secondary meristem is usually the lateral meristem responsible for the increase in thickness of the plant.

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Meristematic Plant Tissues Based on Location

Based on location, the meristematic tissues are of three types: apical or terminal meristem, cambium or lateral meristem, and intercalary meristem.

Location-based plant meristem

Apical or Terminal Meristem:

As the name suggests, the apical meristem is located on the tips of roots and stems and in the growing young leaves near the tips of stems and the tips of axillary buds.

Cambium or Lateral Meristem:

It exists under the bark and is responsible for an increase in the diameter of the stem.

Intercalary Meristem:

They are located in the leaves and internodes and help in increasing the length of the internodes.

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Meristematic Tissues Based on Function

The meristematic plant tissues are of three types – protoderm, procambium, and ground meristem, based on function.

Protoderm:

It is the outermost plant tissue and forms the epidermis. Protoderm is located around the outside of the stem and protects the plant from any mechanical shocks.

Procambium:

It is the innermost tissue and gives rise to the xylem and phloem. It helps in the transport of water and nutrients to different parts of the plant.

Ground Meristem:

The cells are large with thick walls. It forms the cortex, pericycle, and pith.

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Struggling to understand the distinction? Selftution.com – the #1 educational website for simplified learning – breaks it down with easy definitions, real-world examples, and interactive comparisons.

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The difference between non-living and dead depends on whether something has ever experienced life or not. Here’s a simplified explanation:

• Dead things once lived, went through a life cycle, and displayed life characteristics.
• For example, a block of wood or a piece of leather is dead because it comes from living organisms like trees or animals.
• Objects like chairs made of wood or shoes made of leather are non-living because they are products and do not exhibit life.
• Stones, water, and cars are non-living because they were never alive or part of any living organism.

Understanding this distinction becomes clearer when we explore the key traits that define living beings.

Characteristics such as cellular organization, growth, reproduction, respiration, and response to stimuli are fundamental markers of life.

If an object has never demonstrated these traits, it is non-living. However, if it once exhibited them but no longer does, it is dead.

To dive deeper into these traits and their significance, don’t forget to check out my post on the characteristics of living and non-living things for kids!

The difference between non-living and dead

Key Difference Between Non-Living and Dead Things

Understanding the difference between non-living and dead involves analyzing several characteristics that are unique to living organisms. Below is a breakdown of key differences based on life processes:

1. Cellular Organization

• Dead things once had a cellular structure, which is a fundamental characteristic of living organisms.
• Non-living things, on the other hand, do not have a cellular organization or any biological structure.

2. Living Processes

• Dead things once underwent vital processes like nutrition, excretion, and respiration when they were alive.
• Non-living things have never produced or utilized food, nor have they engaged in any metabolic activities.

3. Growth

• Dead things grew in size when alive, as part of their life cycle.
• Any growth seen in non-living things is purely due to external factors, like the accumulation of material, not biological processes.

4. Reproduction

• Dead things once reproduced and gave rise to young ones of their kind when they were alive.
• Non-living things do not and never can reproduce.

5. Locomotion

• While alive, dead things once moved to find food, escape predators, or interact with their environment.
• Non-living things cannot move on their own and remain stationary unless acted upon by external forces.

6. Response to Stimuli

• Dead things, when alive, showed responses to external stimuli, such as light, sound, or touch.
• Non-living things never respond to any changes in their surroundings.

7. Life Cycle

• Dead things once followed a complete life cycle, which included birth, growth, reproduction, and eventual death.
• Non-living things do not have a life cycle, as they have never been alive.

By examining these characteristics, we can clearly distinguish between non-living and dead things. The key lies in whether the object once exhibited the traits of life or never did at all!

Structure of generalized plant and animal cells….Selftution

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