B11-Hormonal coordination

Question 1

What is the endocrine system?

Answer 1

a group of glands that secrete hormones directly into the bloodstream

Question 2

How do hormones work

Answer 2

receptors on the target organ pick up the hormone molecule and trigger a response.

Question 3

What are examples of hormones released by the pituitary gland?

Answer 3

FSH, LH, ADH

Question 4

What is FSH?

Answer 4

causes maturation of egg and secretion of oestrogen

Question 5

What is the order of glands from top to bottom and their function

Answer 5

• pituitary- master gland
• thyroid gland-controls metabolic rate
• adrenal- secretes adrenaline
• pancreas- controls glucose level in blood
• ovary/ testes- controls development of secondary sexual characteristics

Question 6

What is a hormone?

Answer 6

chemical messengers with a target organ

Question 7

Why do we need glucose?

Answer 7

to respire

Question 8

How is the level of glucose detected in the pancreas?

Answer 8

receptors in the pancreas

Question 9

What effect does insulin have?

Answer 9

reduces the amount of glucose

moves glucose from the blood into cells where it can be used for respiration or converted into insoluble starch

Question 10

What happens when the glucose level is too low?

Answer 10

receptors in the pancreas detect the low glucose level and releases a hormone called glucagon. This causes the stored glycogen to be converted back to glucose.

Glucagon interacts with insulin in a negative feedback cycle to control glucose levels.

Question 11

What is type 1 diabetes?

Answer 11

when the pancreas doesn’t produce enough insulin meaning the blood concentration of glucose isn’t monitored
without insulin glucose levels are very high and can eventually glucose is lost through urine
glucose doesn’t go to the cells and they don’t respire causing you to feel tired

genetic

Question 12

What is type 2 diabetes?

Answer 12

linked with obesity and lack of exercise
pancreas makes less insulin than needed
body cells stop responding to the insulin

Question 13

How is type 1 diabetes managed?

Answer 13

• insulin injections after every meal injected into the bloodstream. acts like normal insulin and allows glucose to go into cells
• pancreas transplant
• transplanting pancreatic cells

Question 14

How is type 2 diabetes managed?

Answer 14

• exercise
• healthy diet
• loosing weight

Question 15

What is a negative feedback system?

Answer 15

• work to maintain a steady state

- if changes occur to the environment, a change happens to try to bring the conditions back to normal

Question 16

What is thyroxine and its negative feedback?

Answer 16

• produced by thyroid gland

- controls metabolic rate and how much oxygen is used by tissues

Question 17

What is adrenaline?

Answer 17

• ‘fight or flight’ hormone
• makes heart rate increase and breathing to increase
• stored glycogen to convert to glucose for respiration
• mental awareness to increase

Question 18

What are secondary sexual characteristics?

Answer 18

during puberty sexual hormones cause these:

• growth spirt
• more hair
• F breasts develop
• M testes grow and become active

Question 19

Describe the hormones in the menstrual cycle

Answer 19

FSH is released by pituitary gland which causes egg to mature in the ovary and stimulates the release of oestrogen.

Oestrogen causes the uterus lining to thicken and inhibits the production of FSH

Pituitary gland releases LH which triggers ovulation

Once egg is released it triggers the release of progesterone which stops production of FSH and LH so no more eggs are released and also maintains uterus lining in case of fertilisation

if no fertilisation then progesterone levels fall.

Question 20

FSH

Answer 20

causes egg to mature in ovary

Question 21

LH

Answer 21

causes egg to release ovulation