Control and coordination Worksheet-21

Control and coordination Worksheet-21

Subjective questions:

41. Which plant hormone makes a shoot bend towards sunlight?

42. Where is the auxin hormone made in a plant stem?

43. What type of movement is shown by Mimosa plant leaves when touched with a finger?

44. Name the specialised cell of multicellular animals that perceive external stimuli.

45. Which type of movement is shown by the leaves of 'touch-me-not' when touched?

46. Name the hormone that controls the basal metabolism and its source gland.

47. Name the hormone that controls the water and electrolyte balance in the body and its source glands.

48. What happens at the synapse between two neurons?

49. Which part of the brain maintains posture and equilibrium of the body?

50. How do we detect the smell of an agarbatti (incense sticks)?

51. Give an example of a plant hormone that produces growth.

52. Which signals will get disrupted in case of a spinal cord injury?

Answer:

41. Auxin.

42. The auxin hormone is made in the tip of the stem.

43. Nastic movement.

44. Neurons.

45. Nastic movement.

46. Thyroxine from thyroid glands.

47. Vasopressin from Pituitary glands.

48. At the synapse the two neurons join together.

49. Cerebellum, which is a part of the hind brain maintains the posture and equilibrium of the body.

50. We can detect the smell of an agarbatti (incense sticks) by the olfactory lobes of the fore-brain. The particles of fragrance from agarbatti strike the nerve cells of olfactoreceptor and through motor neurons, impulses are sent to brain where olfactory lobes of fore-brain analyse and produce the sensation of smell.

51. Plant hormone auxin and gibberellin promotes growth of plant.

52. All the signals and responses which pass from and to the brain through the spinal cord will get disturbed. Reflex actions will get disrupted.