![]() When light is coming from one side of the plant, auxin diffuses towards the shady side of the shoot. (b) When growing plants detect light, a hormone called auxin, synthesised at the shoot tip, helps the cells to grow longer. Plant hormones auxin and cytokinin help in cell division. They help to coordinate growth, development and responses to the environment. Ĭhemical control in the plants is performed through plant hormones. (b) Name and explain the role of plant hormone involved in phototropism. Name a plant hormone which is essential for cell division. (a) State the role performed b y plant hormones. (ii) Low glucose level in the blood does not induce the pancreatic cells to produce insulin so that less conversion of glucose to glycogen occurs. (i) High glucose level in blood induces the pancreatic cells to produce more insulin which converts glucose to glycogen. ![]() (b) The timing and amount of hormone secreted are regulated by the “Feedback mechanisms”. (b) Explain with an example how the timing and amount of hormone secreted are regulated in a human body. (ii) Spinal Nerves: Originating from spinal cord. (i) Cranial Nerves: Originating from brain. (b) Peripheral nervous system facilitates the communication between central nervous system and other body parts.Ĭomponents of peripheral nervous system are: (ii) Involuntary actions are controlled by mid-brain (the medulla oblongata). (a) (i) Voluntary actions are controlled by the cerebrum (the forebrain). Name the components of this nervous system and distinguish between their origins. (b) State the significance of peripheral nervous system. (i) voluntary actions (ii) involuntary actions. (a) Name the part of human brain which controls: When the appropriate amount of glucose level is obtained in the blood, the release of insulin is stopped. A feedback mechanism controls the timing and secretion of hormones released by various glands.įor example: On the rise of blood glucose level, information is sent to pancreas to release insulin. Excess or deficiency of such hormones can have harmful effects on our body. Hormones are secreted in extremely less quantity. What is the feedback mechanism of hormonic regulation? Take the example of insulin to explain this phenomenon.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |