Biology SECTION A

              1.       Regular intake of fresh fruits and vegetables is recommended in the diet, since they are a good source of antioxidants, how do antioxidants help a person maintain health and promote longevity?

(a)    They activate the enzymes necessary for vitamin synthesis in the body and help prevent vitamin deficiency

(b)   They prevent excessive oxidation  of carbohydrates, fats and proteins in the body and help avoid unnecessary wastage of energy

(c)     They neutralize the free radicals produced in the body during metabolism

(d)   They activate certain genes in the cells of the body and help delay the ageing process

          2.       Match the following:

List I	List II
A.      Beri- beri        B.      Pellagra       C.      Pernicious anaemia       D.      Scurvy	1.       Vitamin-C       2.       Niacin       3.       Thiamine       4.       Vitamin -B₁₂       5.       Vitamin- A

Codes

                           A   B   C   D

(a)    3   2   4    1

(b)   2   1    5   4

(c)    3   4    2   1

(d)   1   2    3   4

          3.       Consider the following statements in relation to plant tissue chorenchyma

1.       It is formed by the palisade and spongy mesophyll.

2.       It is a form of parenchyma, which contains chloroplasts.

3.       It serves to transport organic solutes made by photosynthesis.

4.       It is a thin transport layer, which has chiefly a protective function.

Which of the statements given above is/ are correct?

(a)    1 and 2

(b)   1,  2 and 3

(c)    2 and 4

(d)   Only 1

          4.       Which of the statements given above is/ are correct?

(a)    1 and 2

(b)   1, 2 and 3

(c)    2 and 4

(d)   Only 1

         5.       Smoking causes oxygen deficiency in the body because of

(a)    Increase in SO₂ levels in blood

(b)   Decrease in O₂ content in blood

(c)    Increase in C0 and C0₂ contents in blood

(d)   Increase in C0 content in blood

        6.       Consider the following statements  regarding osmosis in animals cells

1.       If the water potential of the solution surrounding the cells is too high, the cell shrinks.

2.       If the water potential of the solution surrounding the cell is too low, the cell swells and bursts.

3.       It is important to maintain constant water potential inside the animal body.

4.       In animal cells, water potential far exceeds the solute potential.

Which of the statements given above is/ are correct?

(a)    1 and 2

(b)   Only 3

(c)    Only4

(d)   2 and 3

      7.       The coconut water from a tender coconut is

(a)    An embryo

(b)   A free nuclear endosperm with multiple nuclei

(c)    A cellular endosperm

(d)   A non- nutritive fluid

      8.       Haem is the important biologically in the myoglobin, which is used to store

(a)    Nitrogen in muscles

(b)   Chlorine in muscles

(c)    Oxygen in muscles

(d)   Carbon dioxide in muscles

       9.   Which one of the following is an enzyme?

(a)    Glucagon

(b)   Insulin

(c)    Sometotrophin

(d)   Trypsin

      10.    Sun loving plants are

(a)    Halophytes

(b)   Sciophytes

(c)    Heliphytes

(d)   Autotrophs

Answer:

1.       C

2.       A

3.       B

4.       B

5.       B

6.       A

7.       B

8.       C

9.       D

10.   C