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Plant cell 

1. Cell is comparatively larger with distinct outlines. 

2. Has a definite and rigid cell wall. 

3. Has negligible amount of cytoplasm. 

4. Cytoplasm is not very dense. 

5. Contains plastids. 

6. No centrosome. 

7. Have prominent one or more vacuoles. 

8. Has simple golgi apparatus composed of units called dictyosomes. 

Animal cell 

1. Size is small with less distinct outlines. 

2. Cell wall absent. 

3. Cytoplasm fills almost the entire cell. 

4. Cytoplasm is granular and relatively dense. 

5. Do not contain plastids 

6. Centrosomes are present.

7. Have temporary vacuoles which are small and concerned with secretion or excretion. 

8. Have complex and prominent golgi apparatus.

Cytoplasm 

1. The living portion of the cell inside the cell except the nucleus. 

2. It has many finer parts contained in it like golgi bodies, mitochondria etc. 

Protoplasm 

The living substance of a cell is called the protoplast. 

It consists of two main parts 

1. cytolasm 

2. nucleus.

The most important feature of a living cell is that it can divide or reproduce of its own kind and this function is regulated by the nucleus of the cell. The nucleus in its nucleoplasm contain a network of dark stained thread like structures called chromatin fibres. These fibres during cell division become thick and ribbon like which are then called chromosomes. The chromosomes are the actual hereditary factors. These are unique for each species both in number and in character. Human body has 46 chromosomes which occur in pairs. 

They are further categarised as: 

1. Chromosomes specific for determining the sex of the species called the sex chromosomes. 

2. Other chromosomes are called autosomes.

1. Organisms which are made up of a single cell are called unicellular organisms. 

2. Muscles cells are elongated and contractile. 

3. The jelly-like fluid that surrounds the nucleus of a cell is called cytoplasm. 

4. Plasma membrane is a selectively permeable membrane.

5. The Nucleo plasma contains a network of thread-like structures called chromatin network. 

6. Golgi bodies are also called dictyosomes. 

7. A plant cell gets shape and support from its cell wall. 

8. In a plant cell food is manufactured in chloroplast. 

9. Chromoplasts give colour to flowers and fruits. 

10. Fluid-filled cell organelles that are usually larger in a plant cell than in an animal cell are called vacuoles

1. The cell is the structural unit of all living things. 

2. All cells arise from pre-existing cells. 

3. Animal cells have no cell wall.

4. Plastids contain pigments. 

5. Vacoules are filled with water and dissolved substance

The essential basic parts of a cell are: 

1. Cell membrane 

2. Cytoplasm 

3. Nucleus 

1. Cell membrane — It is a very thin, delicate and flexible membrane which surrounds each cell. It is also called plasma membrane. It consists of fine pores which allow only certain molecules to pass through it and prohibit the others and therefore, due to its function, also called selectively permeable membrane. 

2. Cytoplasm: This is the living portion of the cell which is a semi-liquid, translucent and colourless liquid. It is the portion of the cell where major functions of the cell are carried out through various finer parts of the cell. The finer structures which are contained in this are called the cell organelles. 

3. Nucleus: The small spherical dark coloured body usually located in the centre of the cell. It is the most important part of the cell which regulates and co-ordinates various life processes. Its major role is during cell division. It contains hereditary factors called the genes.

Nucleus and nucleolus 

Nucleus 

1. It is a cell organelle. 

2. It is the most important part of the cell. 

3. It is present in the cytoplasm of the cell. 

4. It is bounded by a delicate nuclear membrane 

Nucleolus 

1. It is a component of the nucleus. 

2. It is the most important part of the nucleus. 

3. It is present in the nucleo plasma. 

. It does not have any such membrane around it

The organelle that controls all activities in 

(a) nucleus  

1. False. 

Correct: The size of a cell is usually measured in micrometres

2. True

3. False. 

Correct: 

At the time of cell division the chromatin network changes into small thread like structures called chromosome.

4. False. 

Correct: Ribosomes are the sites of protein synthesis in a cell.

5. True

6. True

7. False. 

Correct: Only plant cell is bound by a cell wall.

8. False. 

Correct: Chloroplasts are the kitchen of the cell.

9. False. 

Correct: Vacuoles are filled with a fluid called cell sap.

10. True

The vacuole contains: 

(a) water

The term “cell” was coined by Robert Hooke.

Cell wall 

1. It is made up of cellulose. 

2. It gives shape and rigidity to the plant cell. 

3. It is a non-living structure. 

4. It protects the cell from the entry of disease-causing agents, as well the underlying protoplasm against mechanical injuries. 

Cell Membrane 

1. It is very thin, delicate and flexible. 

2. This allows the entry of certain molecules only, while holding back the others. 

3. It is living structure.

4. It has fine pores in it, through which only certain substances carfpass in and out, while others cannot.

The cell membrane of the cell is composed of fine pores through which only certain molecules of the different substances can pass into the cell. Since it allows only specific molecules to enter prohibiting the other it is referred to as Selectively Permeable.

Match the name of the organelle given in Column A with its function given in Column B.

Cell membrane is called selectively permeable membrane as it allows only selected substances to pass through it, and prevents the passage of other substances.

A cell is called the structural unit of life because all living organism irrespective of their size, shape and complexity are made up of cells and functions performed by organism is the result of the activity of the cells in its body.

The life of all multicellular organisms begin with single cell. This cell divided and redivides, there by forming a cluster of many cells. So cell division is necessaiy for growth.

1. Cell division is a process by which a cell divides, forming two new cells. 

2. It is the basis of growth and reproduction of an organism.

All living organisms, unicellular or multicellular are made up of cells. Microscope make it possible to see inside the cells that make up all living organisms. Without microscope we could not see or understand, how life works. So the invention of microscope made it possible to see the basic component of life.

Cell theory was given by Schleiden and Schwann in the year 1838-1839. It was refined further by Rudolf Virchow. 

The main postulates of cell theory are: 

1. All living beings are made up of one or more cells. 

2. Cells are the basic structural and functional unit of all living beings. 

3. All cells are basically alike in chemical composition and metabolic processes. 

4. New cells arise by division of pre existing cells. (Rudolf Virchow)