1. Which of the following statements is correct about receptors ?

Olfactory receptors detect taste and gustatory receptors smell

Auditory receptors detect smell and olfactory receptors detect taste

Gustatory receptors detect taste while olfactory receptors detect smell

Both gustatory and olfactory receptors detect smell

Answer: Gustatory receptors detect taste while olfactory receptors detect smell

Explanation:


2. If there is a deficiency of growth hormone the child becomes _____ ?

Giant

Dwarf

Mentally retarded

Blind

Answer: Dwarf

Explanation:


3. Consider the following statements and choose the incorrect one ?

A gland which does not have a duct and secrets its product directly into the bloodstream is called an endocrine gland.

A gland which secretes its product into a duct tube is called an exocrine gland.

Hormones are the chemical substances which coordinate the activities of living organisms and also their growth.

None of the above.

Answer: None of the above.

Explanation:

all these statements are correct. Hence, your answer will be option [D].


4. Identify which of the following statements about thyroxin is incorrect ?

It regulates protein, carbohydrates and fat metabolism in the body.

Iron is essential for the synthesis of thyroxin.

Thyroxin is also called thyroid hormone.

Thyroid gland requires iodine to synthesize thyroxin.

Answer: Iron is essential for the synthesis of thyroxin.

Explanation:

Iron is essential for the synthesis of thyroxin.


5. Abscisic acid controls ?

cell division

leaf fall and dormancy

shoot elongation

cell elongation and cell wall formation

Answer: leaf fall and dormancy

Explanation:


6. The main effect of cytokinin in plants is to ?

prevent the growth of lateral buds

stimulate cell division

regulate opening and closing of stomata

improve the quality of fruits

Answer: stimulate cell division

Explanation:


7. The leaves of Mimosa are sensitive to ?

heat

touch

smell

light

Answer: touch

Explanation:


8. Reflex arc is formed by ?

muscle -> spinal cord -> receptor

receptor -> spinal cord -> muscle

receptor -> brain -> muscles

muscle -> brain -> receptor

Answer: receptor -> spinal cord -> muscle

Explanation:


9. Which part of a nerve cell contains a nucleus ?

Nerve endings

Cyton

Dendrite

Axon

Answer: Cyton

Explanation:


10. Which part of nervous system controls the reflex activities of the body ?

Cerebellum

Cerebrum

Brain

Spinal cord

Answer: Spinal cord

Explanation: