Plant and animal cells are both eukaryotic cells that contain membrane-bound organelles. Plant cells have a cell wall and chloroplasts for photosynthesis, while animal cells lack these features. The key components of plant cells include the cell wall, cell membrane, chloroplasts, vacuoles, nucleus, and mitochondria. Plant cells vary in shape but are generally cube-shaped. Animal cells come in various irregular shapes and sizes, and their organelles include the nucleus, mitochondria, endoplasmic reticulum, Golgi bodies, and ribosomes. Both plant and animal cells work together through their specialized organelles to carry out functions necessary for survival.

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Organization of Cells
Cell
A cell is the smallest unit of an individual. Many cells together form a tissue. Many tissues together
form the organ. The organs together form the organ system.
Prokaryotic cell
A prokaryote is a single celled organism that lacks a proper nucleus or any membrane bound
organelle. ‘Pro’ means before and ‘karyon’ means nucleus. Most of the prokaryotic cells are bacterial
cells. Genetic material is in the form of a circularised DNA.
Parts of a Prokaryotic cell
1. Cell membrane: Surrounds the cytoplasm of the cell. Responsible for the transport of solutes
inside and outside of the cell
2. Capsule: Helps in attachment of the bacterium to the other bacteria. Also gives virulent
properties to the bacterium.
3. Cytoplasm: Gel like fluid enclosed within the cell membrane. It contains water, enzymes,
salts and other cell components like DNA.
4. Ribosome: Cell structure responsible for protein synthesis
5. DNA: A circular DNA molecule which contains the genetic information and acts like the brain
of the cell.
6. Pili & flagellum: Pili are small cilia like locomotory organelles. Flagellum is a long tail like
organelle used for locomotion

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Eukaryotic cell
1. Plant Cell
Plant cells are eukaryotic cells or cells with membrane bound nucleus. Generally, plant cells are
larger than animal cells and are mostly similar in size and are rectangular or cube shaped. Plant cells
are similar to animal cells in being eukaryotic and they have similar cell organelles.
What is a Plant Cell?
Plant cells are eukaryotic cells. The most important distinctive structure of plant cell is the presence of
the cell wall outside the cell membrane. It forms the outer lining of the cell. The cell wall mostly
constitutes of cellulose and pectin, and its main function is providing support and rigidity. Plants cells
also contain many membrane bound cellular structures. These organelles carry out specific functions
necessary for survival and normal operation of the cells. There are a wide range of operations like
producing hormones, enzymes, and all metabolic activities of the cell.

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Distinctive Features of Plant Cell
The features that are distinctive in plant cells are as follows:
Cell wall provide plant cells rigidity and structural support and cell to cell interaction.
Plastids help in storage of plant products.
Chloroplasts aid in carrying out the process of photosynthesis to produce food for the plants.
Vacuoles are water-filled, membrane bound organelles which stores useful materials.
Plants have specialized cells in order to perform certain functions for the survival of plants. Some cells
manufacture and store organic molecules, others transport nutrients throughout the plant.
Parts of Plant Cell
Plants cell constitute of membrane bound nucleus and many cellular structures. These organelles
carry out functions that are necessary for the proper functioning and survival of the cell. The cell
organelles of the plant are enclosed by a cell wall and cell membrane. The constituents of the cell are
suspended in the cytoplasm or cytosol.
The parts of the plant cell are as follows:
Cell wall is the outermost rigid covering of the plant cell. It is a salient feature of plant cell.
Cell membrane or the plasma membrane is the outer lining of the cell inside the cell wall.
Cytosol or cytoplasm is the gel-like matrix inside the cell membrane which constitutes all other cell
organelles.
Nucleus is the control centre of the cell. It is a membrane bound structure which contains the
hereditary material of the cell - the DNA
Chloroplast is a plastid with green pigment chlorophyll. It traps light energy and converts it to
chemical energy by the process of photosynthesis.
Mitochondria carries out cellular respiration and provides energy to the cells.
Vacuoles are the temporary storage center of the cell.
Golgi body is the unit where proteins are sorted and packed.
Ribosomes are structures that assemble proteins.

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Endoplasmic reticulum are membrane covered organelles that transport materials.
Plant Cell Structure and Function
All parts of the plant play a significant role in the proper functioning of the cell. Unlike animals, plant
cells are surrounded by a rigid cell wall.
Cell wall: The cell wall is a rigid layer that surrounds the plant cells. It is made up of cellulose. Cell
wall is a characteristic feature to cells of plants. Plant cell walls are primarily made up of cellulose.
Plant cell wall consists of three layers: the primary cell wall, secondary cell wall and the middle
lamella. It is located outside the cell membrane whose main function is to provide rigidity, strength,
protection against mechanical stress and infection. Cell wall is made up of cellulose,
pectins,glycoproteins, hemicellulose and lignin.
Cell membrane: It is the outer boundary of the cell, it encloses the cytoplasm and the organelles of
the cells. In plants cells it is inside the cell wall. The cell membrane is semi permeable, allowing only
specific substances to pass through and blocking others.
Chloroplasts: It is an elongated or disc-shaped organelle containing chlorophyll. They have two
membranes and have structures that look like stack of coins. They are flattened structures which
contain chemical chlorophyll. The process of photosynthesis occurs in this region of the plant cell. The
chlorophyll is a green pigment that absorbs energy from sunlight to make food for the plants by
converting light energy into chemical energy.
Vacuole: Vacuoles are known as cells storage center. Plant cells have large membrane bound
chamber called vacuole. Its main function is storage. Vacuoles are found in the cytoplasm of most

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plant cells. They are membrane bound organelles, they perform functions of secretion, excretion and
storage.
Plastids: Plastids are storage organelles. They store products like starch for synthesis of fatty acids
and terpenes.
Golgi complex: The Golgi bodies look like the endoplasmic reticulum and are situated near the
nucleus. They are found in almost all eukaryotic cells. Their main function is to process and package
macromolecules synthesized from other parts of the cell. The Golgi apparatus is referred to as the
cell's packaging center.
Ribosomes: Ribosomes are smallest and the most abundant cell organelle. It comprises of RNA and
protein. Ribosomes are sites for protein synthesis. They are found in all cells because protein are
necessary for the survival of the cell. The ribososomes are known as the protein factories of the cell.
Endoplasmic reticulum: Endoplasmic reticulum is a membrane bound compartment, which look like
flattened sacs lined side by side. It is a large network of interconnecting membrane tunnels. It is
composed of both rough endoplasmic reticulum and smooth endoplasmic reticulum.
They are responsible for protein translation, and protein transport to be used in the cell membrane.
They also aid in sequestration of calcium, and production and storage of glycogen and other
macromolecules.
Mitochondria: Mitochondria are surrounded by two membranes. They are described as the 'power
plants' of the cell as they convert glucose to energy molecules (ATP). They possess their own
hereditary material which help in self-duplication and multiplication.
Lysosome: Lysosome contain digestive enzymes. They digest excess or worn out organelles, food
particles and any foreign bodies. They are called as ‘suicide bags’ of the cell.
Cytoplasm: It is a gel-like matrix inside enclosed by the cell membrane. The cytoplasm supports cell
organelles and also prevents the cell from bursting or shrinking.
Nucleus: It is the control center of the cell. It is bound by a double membrane known as the nuclear
envelope. It is a porous membrane, it allows passage of substances and is a distinctive characteristic
of the eukaryotic cell. Most of the genetic material is organized as multiple long linear DNA molecules.
The nucleus directs all the activities of the cell and also help in protein formation.
2. Animal Cell
All animal cells are multicellular. They are eukaryotic cells. Animal cells are surrounded by plasma
membrane and it contains the nucleus and organelles that are membrane bound. Animal cells are of

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various sizes and have irregular shapes. Most of the cells size range between 1 and 100 micrometers
and are visible only with help of microscope.
Animal Cell Definition
Animal cells are eukarytoic. Animal cells have an outer boundary known as the plasma
membrane. The nucleus and the organelles of the cell are bound by a membrane. The genetic
material (DNA) in animal cells is within the nucleus that is bound by a double membrane. The cell
organelles have a vast range of functions to perform like hormone and enzyme production to
providing energy for the cells.
The components of animal cells are centrioles, cilia and flagella, endoplasmic reticulum, golgi
apparatus, lysosomes, microfilaments, microtubules, mitochondria, nucleus, peroxisomes, plasma
membrane and ribosomes.
Parts of Animal Cell
Animal cell contains membrane bound nucleus, it also contains other membrane bound cellular
organelles. These cellular organelles carry out specific functions that are necessary for the normal
functioning of the cell. Animal cells lack cell wall, a large vacuole and plastids. Due to the lack of the
cell wall, the shape and size of the animal cells are mostly irregular. The constituents of animal cells
are structures like centrioles, cilia and flagella and lysosomes.

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Parts of the animal cell are as follows:
Cell membrane - forms the outer covering of the cell, and is semi-permeable.
Cytoplasm - is a gel-like matrix where all the other cell organelles are suspended inside the cell.
Nucleus - contains the hereditary material DNA and directs the activities of the cell.
Endoplasmic Reticulum - are a network of membranes composed of rough and smooth
endoplasmic reticulum.
Golgi complex - is responsible for storing, packaging of cellular products.
Lysosomes - are enzyme sacs, that digest cellular wastes.
Mitochondria - is the site for cellular respiration and producers of energy.
Ribosomes - are made of RNA and proteins, and are sites for protein synthesis.
Nucleolus - is the structure within the nucleus and helps in synthesis of ribosomes
Cilia & Cilia & Flagella – locomotory organelles
Animal Cell Structure
Animal cells are eukaryotic cells, the nucleus and other organelles of the cell are bound by
membrane.
Cell membrane
 It is a semi-permeable barrier, allowing only a few molecules to move across it.
 Electron microscopic studies of cell membrane show the lipid bi-layer model of
the plasma membrane, it also known as the fluid mosaic model.
 The cell membrane is made up of phospholipids which has polar (hydrophillic) heads and
non-polar (hydrophobic) tails.
Cytoplasm
 The fluid matrix that fills the cell is the cytoplasm.
 The cellular organelles are suspended in this matrix of the cytoplasm.
 This matrix maintains the pressure of the cell, ensures the cell doesn't shrink or burst.
Nucleus
 Nucleus is the house for most of the cells genetic material- the DNA and RNA.
 The nucleus is surrounded by a porous membrane known as the nuclear membrane.
 The RNA moves in/out of the nucleus through these pores.
 Proteins needed by the nucleus enter through the nuclear pores.
 The RNA helps in protein synthesis through transcription process.

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 The nucleus controls the activity of the cell and is known as the control center.
 The nucleolus is the dark spot in the nucleus, and it is the location for ribosome formation.
Ribosomes
 Ribosomes are the site for protein synthesis where the translation of the RNA takes place.
 As protein synthesis is very important to the cell, ribosomes are found in large number in all
cells.
 Ribosomes are found freely suspended in the cytoplasm and also are attached to the
endoplasmic reticulum.
Endoplasmic reticulum
 ER is the transport system of the cell. It transports molecules that need certain changes and
also molecules to their destination.
 ER is of two types, rough and smooth.
 ER bound to the ribosomes appear rough and is the rough endoplasmic reticulum; while the
smooth ER do not have the ribosomes.
Lysosomes
 It is the digestive system of the cell.
 They have digestive enzymes helps in breakdown the waste moelcules and also help in
detoxification of the cell.
 If the lysosomes were not membrane bound the cell could not have used the destructive
enzymes.
Vacuoles
 They are bound by single membrane and small organelles.
 In many organisms vacuoles are storage organelles.
Vesicles are smaller vacuoles which function for transport in/out of the cell.
Golgi bodies
 Golgi bodies are the packaging center of the cell.
 The Golgi bodies modify the molecules from the rough ER by dividing them into smaller units
with membrane known as vesicles.
 They are flattened stacks of membrane-bound sacs.
Mitochondria
 Mitochondria is the main energy source of the cell.
 They are called the power house of the cell because energy(ATP) is created here.
 Mitochondria consists of inner and outer membrane.

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 It is spherical or rod shaped organelle.
 It is an organelle which is independent as it has its own hereditary material.
Cilia and Flagella
 Cilia and flagella are structurally identical structures.
 They are different based on the function they perform and their length.
 Cilia are short and are in large number per cell while flagella are longer and are fewer in
number.
 They are organelles of movement.
 The flagellar motion is undulating and wave-like whereas the ciliary movement is power
stroke and recovery stroke.