Class 10 SELINA Solutions Biology Chapter 1 - Cell - The Structural and Functional Unit Of Life
Cell - The Structural and Functional Unit Of Life Exercise Ex. 1
Solution A.1
(a) Mitochondria
(b) Cell membrane/plasma membrane
(c) Cell wall
(d) Endoplasmic reticulum
(e) Golgi apparatus
(f) Lysosomes
(g) Vacuoles
(h) Chromatin fibres.
(i) Nucleus
(j) Centrosome
Solution A.2
(a) Unicellular animals - Amoeba, Paramoecium
(b) Unicellular plants - Chlamydomonas, Diatoms
(c) Cell organelles - Mitochondria, Nucleus
(d) Cell inclusions - Vacuoles, Granules
(e) Stains which make the nucleus distinct - Iodine, Eosin
Solution A.3
(a) Leucoplast
(b) Anthocyanin
(c) Carotene
(d) Dictyosomes
(e) White blood cells (WBCs)
(f) Red blood cells (RBCs)
(g) Guard cells
(h) Cytosol
(i) Cristae
(j) Cisternae
Solution B.1
(a) Cell: Cell is the structural and functional unit of life capable of independent existence.
(b) Organelles: Organelles are specialized and membrane-bound living structures in a cell concerned with definite functions.
(c) Cytoplasm: Cytoplasm is the part of the cell which is inside the cell membrane and outside the nucleus.
(d) Protoplasm: The living parts of the cell which consist of cytoplasm, nucleus and other living bodies collectively constitute protoplasm or protoplast.
(e) Nucleus: Nucleus is a large spherical body lying nearly in the centre of the cytoplasm.
Solution B.2
(a) Differences between plant cell and animal cell:
|
Plant cell |
Animal cell |
|
1. It is usually larger in size. |
1. It is usually smaller in size. |
|
2. It consists of a definite cell wall made up of cellulose. |
2. It lacks a cell wall. |
|
3. It consists of large and prominent vacuoles. |
3. It consists of small and temporary vacuoles. |
|
4. It consists of less dense cytoplasm. |
4. It consists of denser and more granular cytoplasm. |
(b) Differences between cell wall and cell membrane:
|
Cell wall |
Cell membrane |
|
1. It is the outermost covering in plant cells. |
1. It is the outermost covering in animal cells. |
|
2. It is the non-living and rigid layer. |
2. It is the thin, flexible and living membrane. |
|
3. It is freely permeable. |
3. It is semi-permeable. |
|
4. It is made up of cellulose. |
4. It is made up of lipoproteins. |
(c) Differences between centrosome and chromosome:
|
Centrosome |
Chromosome |
|
1. It is a region surrounding the centrioles located near the nucleus. |
1. It is a highly coiled structure contained within the nucleus. |
|
2. Usually, one centrosome is present per cell. |
2. Several chromosomes can be present per cell. |
|
3. It consists of one or two centrioles. |
3. It consists of DNA coiled around the histone protein core. |
|
4. It initiates and regulates cell division. |
4. It transfers hereditary characters from parents to offspring. |
(d) Differences between chloroplast and chromoplast:
|
Chloroplast |
Chromoplast |
|
1. It is green in colour. |
1. It is variously coloured. |
|
2. It contains the pigment chlorophyll. |
2. It contains pigments such as xanthophyll and carotene. |
|
3. It traps solar energy for photosynthesis. |
3. It imparts colour to flowers and fruits. |
