Short notes
Presentation notes
Content
• Human Endocrine glands, Hormones and their functions.
Presentation notes
Content
• Human Endocrine glands, Hormones and their functions.
• Hormones and homeostasis.
• Hormone related disorders.
• Pheromones
• Plant hormones and functions (Auxins, Cytokinins, Gibberellins, Ethylene, Abscicic acid)
• Synthetic plant hormones.
6. The hormones which maintain the normal rate of glucose in our blood ?
• Hormone related disorders.
• Pheromones
• Plant hormones and functions (Auxins, Cytokinins, Gibberellins, Ethylene, Abscicic acid)
• Synthetic plant hormones.
Questions and answers
1. How is homeostasis maintained?
Homeostasis is maintained by the complementary activities of both quick neural system and slow hormonal system.
2. The chemical substances, secreted by the endocrine glands ?
Hormones.
3. Hormone secreting endocrine glands are also known as 'ductless glands'. Why ?
The hormones secreted by these glands are discharged directly in to blood, not through particular ducts.
4. Though hormones reach all parts of the body, each hormone act at its own target tissues. How is this possible?
Though hormones reach all parts of the body through the blood stream, each hormone act only in its target tissue, having specific receptors for accepting the same hormone. When hormone-receptor complex is formed in the plasma membrane, the enzymes in the cells become active.
5. The table and illustration showing the endocrine glands, site and producing hormones.
Insulin, Glucagon.
7. What is the normal level of glucose in blood? How is it maintained?
70 – 110 mg /100 ml blood.
This rate is maintained by the antagonistic activities of insulin and glucagone , released from Islets of Langerhans of the pancreas. When glucose increases in blood, beta cells in the Islets of Langerhans secretes insulin. It accelerates the process of glucose intake by the cells and conversion of the excess glucose in to glycogen.
When glucose decreases in blood, alpha cells in the Islets of Langerhans secretes glucagon, which converts glycogen and amino acids in to glucose.
8. Islets of Langerhans : Alpha cells : Glucagon ;
Islets of Langerhans : Beta cells : .................?
Insulin..
9. The reason for --------------, (the blood glucose level more than 126mg/100ml) is the deficiency or inactivity of the hormone insulin.
Diabetes mellitus.
10. Patients having diabetes mellitus usually takes insulin injection. Why ?
Insulin maintains the normal rate of glucose in our blood.
11. World Diabetics Day ?
November 14.
12. Name the endocrine glands A and B
shown in the figure.
A- Thyroid gland, B- Parathyroid gland.
13. The chief metabolic hormone ? The hormone that control the basal metabolic rate (BMR) ?
Thyroxine.
14. The element needed for the proper functioning of thyroid gland ?
Iodine. (Deficiency of iodine may cause a disorder, Goitre)
15. A doctor advised one of his patients to include iodised salt and sea food in his diet. What could be the reason ?
The patient need iodine to prevent goitre.
16. Mention the functioning of hormones secreted by thyroid gland.
Thyroxine – Increases the rate of metabolism, energy production, accelerates the development of brain in the foetal stage and infancy, regulates growth in children.
Calcitonin – Maintains the level of calcium in blood by depositing excess calcium in bones or by preventing the mixing of calcium with blood (from the bones).
17. Under secretion of thyroxine : Hypothyroidism,
Over secretion of thyroxine : .................................. ?
Hyperthyroidism.
18. Symptoms of hypothyroidism and hyperthyroidism.
19. Give examples for the conditions due to hyperthyroidism and hypothyroidism.
Hypothyroidism - Cretinism, Myxoedema
Hyperthyroidism - Grave's disease.
20. Deficiency of thyroxine during infancy may cause ---------, stunted physical-mental growth in children.
Cretinism.
21. The prolonged secretion of thyroxine (hyperthyroidism) may cause a disease
called ------- characterized by the bulging of eye balls.
Grave's disease.
22. The hormones which maintain the normal rate of calcium in our blood ?
Calcitonin of thyroid gland, Parathormone of parathyroid gland.
23. What is the normal level of calcium in blood? How is it maintained?
9-11 mg /100 ml blood.
When the level of calcium in blood increases, thyroid gland secretes calcitonin, which lowers the level of calcium in blood, by depositing excess calcium in bones or by preventing the mixing of calcium with blood (from the bones).
When the level of calcium decreases in blood, parathyroid gland secretes parathormone, which increases the level of calcium by helping in its re-absorption from kidneys or by preventing the deposition of calcium in bones.
24.The endocrine gland that active during infancy ? Name its hormone ?
Thymus gland (situated below the sternum / chest bone). Secretes the hormone 'thymosin'.
25. Thymosin is also known as the 'youth hormone'. Why ?
During infancy, thymosin helps in the maturation and activities of lymphocytes and hence it is also known as the 'youth hormone'.
26. Table which shows the functions of hormones of adrenal cortex and medulla.
27. Name the hormone that can be used as medicine against allergy and inflammation. Is it advisable to diabetic patients ? Why ?
Cortisol of the adrenal gland.
Since cortisol increases the synthesis of glucose, it is not advisable to diabetic patients.
28. How is epinephrine or norepinephrine prepare our body to overcome emergencies?
When the sympathetic nervous system gets stimulated, the action of epinephrine or norepinephrine prolongsthe body activities for more time. Due to these activities we get energy to resist or withdraw ourselves from such situations.
29. Why does the pineal gland, seen in the centre of our brain, called as a 'biological clock' ?
Melatonin, the hormone of pineal gland, helps to maintain rhythm of our daily activities like awakening, asleep or definite reproductive periods. So the pineal gland is called as a 'biological clock'.
30.Name the bilobed gland situated just below the hypothalamus.
Pituitary.
31. What are the hormones produced by the hypothalamus ?
Releasing hormones : It stimulate the anterior lobe of the pituitary to secrete
tropic hormones and other hormones.
Inhibitory hormones : It inhibit the production of hormones from the pituitary.
Oxytocin and vasopressin (ADH) : These are stored in the posterior lobe of
pituitary.
32. Name the hormones secreted by the anterior lobe of pituitary. Mention their functions too.
• Tropic hormones.
- TSH (Thyroid stimulating hormone)- Stimulates the activity of thyroid gland.
- ACTH (Adreno cortico tropic hormone)- Stimulates the activity of adrenal cortex.
- GTH (Gonado tropic hormone)- Stimulates the activity of sex organs.
• STH (Somato tropic hormon /GH -Growth hormone)- Promotes the growth of the body.
• Prolactin – Production of milk.
33. Hormones which are stored in the posterior lobe of pituitary ? Their functions ?
• Oxytocin - Facilitates child birth by stimulating the contraction of smooth muscles in the uterine wall
- Facilitates lactation .
• Vasopressin - Helps in the re-absorption of water in the kidneys and thus act as Anti Diuretic hormone
(ADH).
34. How can hypothalamus control the entire endocrine system ?
Pituitary controls certain important glands through its various Tropic hormones, which are secreted under the influence of a variety of Releasing and Inhibitory hormones of the hypothalamus.
Releasing hormones stimulate the anterior lobe of the pituitary to secrete tropic hormones and other hormones while the Inhibitory hormones inhibits the production of hormones from the pituitary.
35. Name the growth disorders related to the growth hormone (somatotropin / STH) of the pituitary.
Dwarfism - The condition characterised by stunted physical growth due to decreased production.
Gigantism – Excessive growth of the body due to increased production of Somato Tropic Hormone.
Acromegaly – Excessive growth of the bones on face, jaws and fingers due to the prolonged production of STH even after the growth phase.
36. Mention the symptoms of acromegaly.
Excessive physical growth with excessive growth of the bones on face, jaws and fingers.
37. Describe about the reason for decreased production of urine during summer season.
During summer season, the production of vasopressin(ADH) increases and there fore re-absorption of water in the kidneys increases, to lower the quantity of urine.
38. The condition in which excess amount of urine is excreted, even in summer season, due to the insufficient production of vasopressin, is known as ---------- ?
Diabetes insipidus .
39. Insulin : Diabetes mellitus : Glucose, Vasopressin : --------?-------- : water.
Diabetes insipidus.
40. Table showing sex organs, hormones and their functions?
41. Hormonal disorders.
42. Define pheromones. How is it useful to animals ?
Pheromones are chemical substances that are secreted in trace amount to the surrounding in order to facilitate communication among organism.
It help in attracting mates, informing about food, determining the path of travel, informing about dangers, help honey bees and termites to live in colonies etc.
[Artificial pheromones are used for controlling pest in agricultural field.]
43. Give examples of pheromones
The musk in the musk deer,
The civeton in civet cat ,
Bombycol in female silkworm .
44. Ants can follow one after another during their trail. How is this possible ?
Because of the chemicals, pheromones, that released to their surroundings.
45. How the life activities are controlled and coordinated in plants ?
Certain plant hormones (plant growth regulators) control and coordinate life activities in plants.
46. Table showing the natural plant hormones and their activities.
47. Name the plant hormone in gaseous form.
Ethylene.
48. The utility of artificial or synthetic plant hormones.
49. Give examples of situations where artificial plant hormones are applied .
Ethylene is used for the flowering of pineapple plants at a time and for the ripening of tomato, lemon, orange etc.
Ethyphon, in liquid form gets transformed into ethylene, increases the production of latex.
Gibberellins are used for increasing fruit size in grapes and apple and also for preventing ripening of frutis to assist in marketing.
50. The activity of auxins in stem and root is different. Substantiate.
True. Auxins promote the growth of terminal bud in stem, but prevent the growth of roots.
51. Though artificial plant hormones are useful, its application should be with utmost care. What is your opinion ?
True. Majority of the synthetic plant hormones are strong chemicals.
