endocrine system

Question 1

where are hormones produced (2)

Answer 1

ductless or endocrine glands

Question 2

what is method 1 of hormone action

Answer 2

when hormones bind to receptors on the cell surface and a second messenger sends the signal into the cell

Question 3

what is method 2 of hormone action

Answer 3

no second messenger is involved. Hormones alter the target cells by activating DNA

Question 4

what is the function of the hypothalamus in the endocrine system

Answer 4

produce hormones (releasing hormones) that stimulate other glands to make hormones

Question 5

what is the purpose of the pituitary gland

Answer 5

produces stimulating hormones which stimulate other glands to make hormones

Question 6

what is the function of the anterior pituitary

Answer 6

receive hormones from the hypothalamus via blood supply

Question 7

what is the function of the posterior pituitary

Answer 7

receive nerve supply from the hypothalamus triggering hormone broduction

Question 8

what does the posterior pituitary gland produce (2)

Answer 8

ADH (anti-diuretic hormone) - involved in water balance.
oxytocin - stimulates labour contractions, promotes a sense of well-being & maternal bonding and behaviour.

Question 9

what does the anterior pituitary gland produce (2)

Answer 9

growth hormone
stimulating hormone

Question 10

what hormones does the thyroid produce (3)

Answer 10

thyroxine (T4) - regulates BMR (basal metabolic rate)
triiodothyronine (T3) - regulates BMR (basal metabolic rate)
calcitonin

Question 11

what does the parathyroid produce

Answer 11

hormones which regulate calcium levels

Question 12

what does calcitonin regulate

Answer 12

how much calcium is deposited the in bone

Question 13

what happens when thyroxine levels fall (5)

Answer 13

The hypothalamus stimulates the pituitary.
The pituitary stimulates TSH (thyroid stimulating hormone.)
The thyroid responds to TSH and secretes thyroxine.
Thyroxine enters the blood and affects the metabolic rate of all cells.
Rising levels of thyroxine stops the brain from producing TSH and the mechanism switches off.

Question 14

what should the blood glucose levels be before a meal and after

Answer 14

before a meal = 4 - 5.9 mmol/L
after a meal = under 7.8 mmol/L

Question 15

where is glucagon and insulin produced

Answer 15

in the pancreatic islets
Glucagon - alpha cells
Insulin - beta cells

Question 16

how does insulin work

Answer 16

binds to receptors on the cell surface and triggers reactions inside the cell. Resulting in glucose transport proteins bringing glucose into the cell.

Question 17

how does glucagon work

Answer 17

travels to the liver from the pancreas and converts glycogen into glucose to be released into the bloodstream. switched on during exercise and when hungry and is regulated by the SNS

Question 18

what happens when there is a fall in glucose (4)

Answer 18

insulin secretion decreases and glucagon is produced.
less glucose is taken up by cells and respired.
stored glycogen in the liver and muscle is converted into glucose by glycogen.
fatty acids are converted into glucose.

Question 19

what is the difference between type 1 and type 2 diabetes

Answer 19

1 - islets are attacked
2 - body is unable to use insulin effectively enough.

Question 20

what happens to the pancreatic islets as we age

Answer 20

they produce less insulin.
excess fat and sugar reduces the number of insulin receptors available.

Question 21

what kind of disorder is hyperthyroidism

Answer 21

metabolic disorder

Question 22

how is glucose regulated in the bloodstream (5)

Answer 22

pancreatic receptors detect glucose rise.
hypothalamus relays information to the pituitary to allow insulin secretion.
insulin converts glucose to glycogen.
The mechanism switches off when high levels of glucose are reached.
Vise versa when glucose levels fall