Short Questions of Cell:-
1.What will happen if the already swollen raisin is kept in salt solution?
Sol: The water flows out from the raisin and goes into the solution medium. Consequently, the raisin shrinks in size.
2.What is the function of Cellulose in a plant cell?
Sol: The plant cell wall is mainly composed of cellulose. Cellulose is a complex substance which provides structural strength to plants.
3. Name two structures which are found in plant cell , but not in animal cell.
Sol: Chloroplast and cell wall are found in plant cell but not in animal cell.
4. What is dictyosomes?
Sol: In plants, Golgi bodies are called as dictyosomes.
5. Is there any animal cell that lack lysosomes ?
Sol: Yes, Mammalian RBCs (Red Blood Corpuscles) lack lysosomes.
6. Name the energy currency of cell
Sol: Adenosine Triphosphate (ATP) is considered by biologist to be energy of the cell.
7. What is the name of membrane of the vacuole of plant cell?
Sol: Tonoplast is the name of membrane of the vacuole of plant cell.
8. “ A cell is building block of an organisms “ - Explain why?
Sol: The body of an organisms is made up of various organ systems and these organ systems are made up of various tissue and tissues are the group of cells performing same function. Hence, cell is building block of an organisms.
9. “ Every multicellular organisms has arisen from a single cell. “ – Justify this statement.
Sol: Cell divided to produce cells similar to themselves. Thus, all cells are derive from the pre-existing cells and every multicellular organisms has arisen from a single cell. E. g., development of human start from a single diploid cell called zygote formed by the fussion of an ovum and sperm.
10.Illustrate the various function performed by the cell.
Sol: Cell perform various function performed by a cell are given below –
(i) Synthesis of substance like protine and lipids.
(ii) Secretion of enzymes.
(iii) Removel of dead material.
(iv) Oxidation to generate energy.
11.What do you mean by plasmolysis?
Sol: When a living plant cell loses water through osmosis, shrinkage or contraction of the cell contents away from the cell wall occurs. This phenomenon is known as plasmolysis.
11. What would happen, if cell wall is not
Present in plant cell?
Sol: (i) Shape of cell will not remain definite because cell wall provides structural strength to plant cell.
(ii) Cell will not be able to withstand pressure and burst, if placed in very dilute media.
Foreign
12. Give scientific reasons for the following:
i) Inner membrane of’ mitochondria is
deeply folded.
(ii) Mitochondria are able to make some of
Their proteins.
Sol: (i) Inner membrane of mitochondria is deeply
Folded as these folds create large surface area for ATP generating chemical reactions.
(ii) Mitochondria contain their own DNA and
Ribosomes and hence, can make their own
Proteins.
13. Bacteria do not have chloroplast, but some
Bacteria are photoautotrophic in nature
And perform photosynthesis. Which part of bacterial cell performs this?(NCERT Exemplar)
Sol: Bacterial cell do not have chloroplast yet some photoautotrophic bacteria perform photosynthesis due to the presence of light absorbing pigments and reaction centres embedded in the cell membrane.
The reaction centres exist in forms of sacs, tubes or sheets depending on the amount of surface area needed.
14. Name the two cell organelles, which are
Bound by a double layered membrane. Give
One function of each.
Sol: Mitochondria-site of ATP generating reactions.
Chloroplasts- site of photosynthesis.
15. Give one word answer to the following:
(i) Organelle containing chlorophyll.
(ii) An organelle with cristae.
(iv) An organelle with ribosomes attached to
Its surface.
(v) Living matter of the cell.
Sol. (i) Chloroplast
(ii) Mitochondria
(ii) Rough endoplasmic reticulum
iv) Protoplasm
16. Why do some regions appear darker than
Other regions on staining the cell with
Methylene blue? Name the other solutions
That can be used for staining?
Sol: Different regions of cells get coloured differentially due to their chemical composition.
Other solutions that can be used for staining are
Iodine solution or safranin solution.
17. Why does the skin of your fingers shrink when you wash clothes for a long time?(NCERT Exemplar)
Sol: The solution of soaps and detergents are hypertonic as compared to the osmotic concentration of our skin. Therefore, washing of clothes results in exosmosis in skin cells that come in contact with the soap solution. Due to this reason, the skin of the fingers shrinks while washing clothes for a long time.
18. A person takes concentrated solution
Of salt. After sometime he starts vomiting.
What is the phenomenon responsible for
Such a situation? Explain. NCERT Exemplar
Sol: Solution of salt is hypertonic in nature, so causes irritation and excessive dehydration due to exosmosis in intestine. This makes the person
Uncomfortable causing reverse movements as
Vomiting.
19. What do you mean by the following terms?
(i)Protoplasm
(ii) Cytoplasm
(iii) Nucleoplasm
Sol: i) Protoplasm It is the living substance present in the cell containing both cytoplasm and nucleoplasm.
ii) Cytoplasm It is a part of protoplasm filled within the space between the nuclear membrane and cell membrane. It is homogeneous in nature
containing water, amino acids, oxygen etc.
iii) Nucleoplasm It is a transparent, semi-fluid
substance filled within the space between nuclear membrane and nucleolus. It consists of nucleic acids, basic and acidic proteins, lipids and
minerals.
20. Name the process by which unicellular fresh water organisms and most plant cells from surrounding medium.
Sol: Endosmosis, I. e. inward movement of the water into the cell from the surrounding medium.
Long Questions of Cell:-
1.Explain main functional region of a cell with the help of a explain.
Sol: Plasma membrane, cytoplasm nucleus are three main functional region of cell.
(I) Plasma membrane It is a thin, selectively permeable membrane, covering the cell and is made up of lipids and proteins . It is about 7nm thick. And in 1972,S.J.Singer and G. L. Nicolson suggested a model, called fluid mosaic model for explaining the ultar structure of plasma membrane. It gives shape, protect, to the cell.
(II) Cytoplasm It is aqueous material containing a variety of cell organelles along with non-living inclusions. It is formed of proteins, nucleic acids, carbohydrates, lipids and certain inorganic substance.
(III) Nucleus It is the most essential part of a cell. It compared with the control room of the factory . It was first discovered by Robert Brown in 1831.The nucleus is usually spherical, oval shape and it is in the center of the cell. Nucleus is bonded by double membrane called nuclear envelop and it is connected with ER. There is some pores on nuclear envelop called nuclear pores. The unclear envelop enclose the nuclear sap or nucleoplasm. Within nuclear sap there are nucleolus and chromatin material.
2.Write the main function of ten cell components. With a proper label diagram.
Sol:
(I) Plasma Membrane It acts as a semipermeable membrane and allows only selective substance to pass through it.
(II) Chromosome To carry hereditary character of an organisms from one generation to another.
(III) Lysosomes Breakdown (by hydrolytic enzymes)of unwanted Macromolecules is the main function of this organelle.
(IV) Ribosomes This helps in protein synthesis.
(V) Nucleus Control centre of the cell. Contains cellular DNA in forma of genes.
(VI) Mitochondria The main function in mitochondria in aerobic cells is the production of energy by synthesis of ATP.
(VII) Cell Wall It provide protection and rigidity to the plant cell.
(VIII) Chloroplast These are the sites of photosynthesis within the sites the plant cell.
(IX) Endoplasmic Reticulum Severs as channel for transport of the material.
(X) Nucleolus Biosynthesis of ribosomal (rRNA) and act as a platform for protein at.
3.Grass look green, papaya appears yellow. Which cell organelles is responsible for this? [CBSE 2016]
Sol: Plastid these are found in plant cell only. Plastids are the major cell organelles in plant. On the basis of pigment present in plastid, they are divided into two types ; i)the colourless leucoplast and ii) the pigmented chloroplasts. The colourless leucoplast store starch, oil and protein granule whereas the pigmented chloroplast have different colours and can be of several types. The most important ones are those containing chlorophyll know as chloroplast which is responsible for the preparation of food by photosynthesis. Other Chromoplast contain non – green pigment, which are responsible for the characterization colours of fruit and flower.
For detailed information **
Name of the Plastid | Pigment present | Function | Location |
Chloroplast | Green (called chlorophyll) | Involved in the photosynthesis of food | Leaves |
Chromoplast | Any colour other than green | Impart attractive colour to flower and fruit | Coloured part of plant |
Leucoplast
| No pigment (Colourless) | Store starch, oilamd protein etc. | Underground part of plants |
4.Give brief description on discovery of cell.
Sol: Robert Hooke (1665) is credited with the discovery of cell. When Hooke made his chance observation a honey comb -like pattern with his crude microscope. It is looking like a small room So, the name given as ‘cell' because in Latin small room is called cell.
In 1674 , Anton Van Leeuwenhoek discovered free cell like bacteria , protozoa, red blood cells and sperms with the help of an improve microscope. Robert Brown in 1831 discovered the nucleus in the cells. In 1839,Johannes Purkinje named the cell is a mass of protoplasm.
5.Write the difference between prokaryotic and eukaryotic cells.
Sol. Difference between prokaryotic and eukaryotic cells are given below –
Sl. No | Feature | Prokaryotic cell | Eukaryotic cell |
1 | Size | Small, (1-10 μm) | Large, (5-100 μm) |
2 | Cell | Non Cellulosic | Cellulosic in plants only |
3 | Cell Organelle | Absence except ribosomes | Present, e.g., mitochondria, endoplasmic reticulum, Golgi apparatus, lysosomes, Peroxisomes, Plastids, etc. |
4 | Nuclear Membrane | Absent. Nucleoid or nuclear region is not surrounded by nuclear membrane, i.e., DNA is naked. | Present. DNA is surrounded by a nuclear membrane. |
5 | Nucleolus | Absent | Present |
6 | Cytoskeleton | Absent | Present |
7 | Chromosomes | Single | More then one |
8 | Cell division | By fission or budding | Mitotic or meiotic |
6. Write about active and bulk transport. And short the difference between endocytosis and phagocytosis.
Sol: Active Transport It involved movement of material across the plasma membrane using energy in form of ATP. It is very fast method. It also involves transport of large amount of substance across the plasma membrane using energy by special methods : (a) Endocytosis (b) Exocytosis.
Bulk Transport It involves transport of large amount of substance across the plasma membrane using energy by special methods :
(a) Phagocytosis ( cell eating)
(b) Pinocytosis (cell drinking)
Difference between endocytosis and exocytosis are given below –
Endocytosis | Exocytosis |
1.It is the intake of extra – cellular fluid, droplet and macromolecules. | 1.It is the intake of extracellular particles. |
2.Plasma membrane invagination to take up the material. | 2.Plasma membrane grows around the particles as pseudopodia. |
3.It is nutritive process. | 3.It is a nutritive and a defensive process. |
4.Endocytotic vesicles are only 0.1μm wide. | 4.Phagocytasis vesicles are 1to 2 μm or more wide. |
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