Question

Give one key difference between:
Plant cell and animal cell
1) Cell wall is absent in plant cell and present in animal cell
2) Cell wall is present in plant cell and absent in animal cell
3) Chloroplast is absent in plant cell and present in animal cell
4) Vacuole is absent in plant cell and present in animal cell

Answer 1

Hint: Cell wall is an additional non-living, rigid structure present in plant cells It is also present in cells of Bacteria, Algae and Fungi. It has a protective function.

Complete Answer:
Plant cells possess cell walls and this feature distinguishes them from animal cells. Cell wall is a non-living, outermost covering of plant cells which is formed by the living protoplast. Besides the plant cells, the cells of Bacteria, Fungi and Algae also have cell walls but the composition cell wall is different in different groups.
(a) Plant cell wall: Plant cell wall is mainly composed of cellulose, hemicellulose and pectin.
(b) Bacterial cell wall: Bacterial cell wall is composed of special macromolecules called peptidoglycan murrain or mucopeptides) Peptidoglycan is the polymer of N- acetyl muramic acid (NAM) and a cetylglucosamin (NAG).
(c) Fungal cell wall:Fungal cell wall is mainly composed of chitin-chitin is the polymer of N-acetyl glucosamine (NAG).
(d) Algae cell wall: Algae cell wall is composed of cellulose, mannars, galactans and minerals like calcium carbonate.

Formation of cell wall: Cell wall is formed from Phragmoplast luring the cell plate formation and cytokinesis cell wall of plant consist of following regions:
(i) Primary cell wall:The initial wall of young plant cells is called primary cell wall It is thin , elastic and expansive meristematic and paren chymatous cells have only primary cell wall.
(ii) Secondary cell wall: It is thick, rigid, permeable and lies near the plasma membrane or tertiary cell wall (in same case):- Thickening of secondary cell wall due to high deposition of lignin as well as suberin
(iii) Middle Lamella:Middle lamella is a thin, sticky and amorphous cementing material that is present between the adjacent cell for making plant tissue ? at is composed of calcium and magnesium pectate.

Hence the correct answer is option ‘C’ .

Note: Cell walls protect the cell from mechanical as well as pathogenic attacks .It maintains the cell shape and helps in cell to cell interaction. Chloroplast not present in animal cells and vacuoles are present in both animal and plant cells but much more larger in plant cells.