Question

1. What are receptors?
2. Name taste and smell receptors?
3. Why we are unable to taste the food properly when we are suffering from cold?
4. What are turgor movements in plants?
5. Diagrammatically explain reflex arc, and show the pathway of the stimulus.
6. Name the parts of the human brain and roles performed by each part of the brain.
7. Name at least four plant hormones and one role of each hormone.
8. Differentiate between electrical and chemical impulse.
9. Explain phototropism with the help of suitable activity.
10. Explain geotropism with the help of suitable activity.
11. Give four examples of reflex actions in our day to day life.
12. Explain feed-back mechanism with suitable example.
13. Why do the leaves of touch-me-not plant droop- down on touching?
14. Which hormone is known as "fight or flight" hormone? Why 15. Elderly people are normally advised to take less sweet by the doctors. Why.
16. Draw a well labelled diagram of human brain.

Answer 1

Explanation:

1. an organ or cell able to respond to light, heat, or other external stimulus and transmit a signal to a sensory nerve.
2. Both smell and taste use chemoreceptors, which essentially means they are both sensing the chemical environment. This chemoreception in regards to taste, occurs via the presence of specialized taste receptors within the mouth that are referred to as taste cells and are bundled together to form taste buds.
3. But when we a have cold, due to the mucus in our nose we are not able to smell the odor and hence our brain is not able to tell us about the flavor of the dishes that we are having. As a result we feel that our food tastes bland and we do not feel like having anything when we are sick.
4. Definition of turgor movement. : a reversible change in position of a plant part due to a change in turgor pressure of various cells (as in sleep movements) — compare nyctitropism.