hormones

Question 1

hormone

Answer 1

-hormones are chemical substances produced by glands, which are carried by the blood, which alters the activity of one or more specific target organs and is destroyed by the liver

Question 2

anti-diuretic hormone

Answer 2

-endocrine gland - hypothalamus produces ADH, pituitary gland stores and releases ADH
-function - osmoregulation
-target organs - walls of collecting duct

Question 3

insulin and glucagon (secreted directly into bloodstream)

Answer 3

-endocrine gland - islets of langerhans in pancreas
-function - blood glucose regulation
-target organs - insulin is liver and muscle cells, glucagon is liver cells only

Question 4

adrenaline

Answer 4

-endocrine gland - adrenal glands
-function - produced under situations of fear, stress, anger, anxiety
-target organs - heart, lungs, pupils of eyes

Question 5

oestrogen and progesterone

Answer 5

-endocrine gland - ovaries
-function - regulation of menstrual cycle
-target organs - uterine lining/ endometrium

Question 6

higher blood glucose above norm

Answer 6

-islets of langerhans of pancreas is stimulated
-insulin is secreted by the islets of langerhans
-signals liver and muscle cells to convert excess glucose to glycogen for storage
-increases permeability of cell membrane to glucose which increases uptake of glucose into cells
-the concentration of glucose in the blood is reduced back to norm

Question 7

lower blood glucose below norm

Answer 7

-islets of langerhans of pancreas stimulated
-glucagon is secreted by islets of langerhans
-signals liver cells to convert glycogen back to glucose, which is then released into bloodstream
-blood glucose concentration is raised back to norm

Question 8

type 1 diabetes

Answer 8

-islets of langerhans of pancreas produces insufficient insulin
-beta cells that produce insulin are destroyed by autoimmune disease
-tends to develop during childhood
-requires insulin injections to replace missing hormone

Question 9

type 2 diabetes

Answer 9

-islets of langerhans of pancreas produces insulin
-target cells do not respond to insulin production, caused by the down-regulation of insulin receptors on target cells
-tends to develop during adulthood
-controlled by managing diet and lifestyle

Question 10

immediately after a meal,

Answer 10

-glucose cannot be stored in the liver and muscles as glycogen, thus blood glucose levels remain high
-blood glucose concentration can reach a level that exceeds the kidney’s ability to completely reabsorb all the glucose
-the glucose that is not reabsorbed is excreted in the urine

Question 11

after a period of dieting/ starving,

Answer 11

-the body oxidises fats instead of glucose to release energy
-results in the production of ketones which are excreted in urine

Question 12

long term effects of diabetes mellitus

Answer 12

-increased risk of coronary heart disease, kidney failure, blindness

Question 13

adrenaline and target organs

Answer 13

liver and muscle
-increased conversion of stored glycogen to glucose
-glucose is needed for respiration which releases energy

heart
-increased heart rate
-increased volume of blood pumped per unit time, increasing glucose and oxygen supply to muscle for respiration

lungs
-increased breathing rate
-increased absorption of oxygen, which is needed for respiration

brain
-increased blood flow to the brain
-brain can think more clearly

muscle
-increased blood flow to the muscle
-blood contains oxygen and glucose can reach muscles, where aerobic respiration occurs

eyes
-dilation of pupils
-allows more light to enter the eyes for enhanced vision

digestive system, kidneys, skin
-decreased blood flow
-more blood can be transported to brain and muscles