Cell Structure and Functions-NCERT Solutions

1.  (a)  True

      (b)  True

      (c)  False

      (d)  True

2.  Sketch of human nerve cell- refer to NCERT text book -

      Function of nerve cell – (a) it helps in the transfer of messages from various body parts to brain and from brain to various body parts of the body.

      (b) Nerve cells help in coordination of the functions of the organs of body.

3.  (a) Cytoplasm- it is a jelly like substance which is present between nucleus and the cell membrane. There are various other organelles present in the cytoplasm. It is made up of carbohydrates, proteins and water.

      (b) Nucleus of a cell- Nucleus is a dense, spherical structure situated in the centre of a cell. Nuclear membrane separates the nucleus from cytoplasm. It contains genetic materials like RNA and DNA.

4.  Cytoplasm contains organelles.

5.  Diagrams of plant and animal cell- refer to NCERT textbook -

      Differences:

6.  Eukaryotes have a well designed nucleus and organelles covered with membranes but prokaryotes do not have a well designed nuclear membrane.

7.  Chromosomes are present in the nucleus of the cell and they carry characteristics of parent cells to daughter cells.

8.  Numerous cell units combine to form tissues. These tissues combine to form organs which form a complete body. Hence cell is the structural unit of an organism that perform all basic functions of life.

9.  Photosynthesis is the main process in plants which takes places in the presence of chlorophyll which is found in chloroplasts. That’s why chloroplast is found only in plant cells.