71.

A potted plant was taken in order to prove a factor necessary for photosynthesis. The potted plant was kept in the dark for 24 hours. One of the leaves was covered with black paper in the centre. The potted plant was then placed in sunlight for a few hours.

(i) What aspect of photosynthesis was being tested?

(ii) Why was the plant placed in the dark before beginning the experiment?

(iii) During the starch test, why was the leaf

(1) boiled in water

(2) boiled in methylated spirit

(iv) Write a balanced chemical equation to represent the process of photosynthesis.

(v) Draw a neat diagram of a chloroplast and label its parts.

The diagram given below is a representation of a certain phenomenon pertaining to the nervous system. Study the diagram and answer the following questions:

(i) Name the phenomenon which is being depicted.

(ii) Give the technical tenn for the point of contact between the two nerve cells.

(iii)Name the parts 1, 2, 3 and 4.

(iv)Write the functions of parts Sand 6

(v) How does the arrangement of neurons in the spinal cord differ from that of the rain?

Given below is a diagram representing a stage during mitotic cell division.

Study it carefully and answer the questions which follow:

(i) Is it a plant cell or an animal cell? Give a reason to support your answer.

(ii) Identify the stage shown.

(iii) Name the stage which follows the one shown here. How is that stage identified?

(iv) How will you differentiate between mitosis and meiosis on the basis of the chromosome number in the daughter cells?

(v) Draw a duplicated chromosome and label its parts.

The given diagram represents a nephron and its blood supply. Study the diagram and answer the following questions: 
 

i. Label parts 1, 2, 3 and 4.

ii. State the reason for the high hydrostatic pressure in the glomerulus.

iii Name the blood vessel which contains the least amount of urea in this diagram.

iv. Name the two main stages of urine formation.

v. Name the part of the nephron which lies in the renal medulla.