Hormones

Question 1

What are hormones

Answer 1

Chemical molecules released directly into the blood. They are carried in the blood to other parts of the body but only affect particular cells in particular organs called the target organs

Question 2

Where are hormones produced and what is their function

Answer 2

Produced in various glands called endocrine glands which make up the endocrine system. Hormones control things in organs and cells that need constant adjustment. They tend to have long-lasting effects

Question 3

6 Examples of glands

Answer 3

Pituitary gland- regulate body conditions, these hormones act on other glands, direct them to release hormones, can be called the master gland
Thyroid- prodcues thyroxine which regulates rate of metabolism, heart rate and temperature
Adrenal gland- produces adrenaline, prepares the body for ‘fight or flight’
Pancreas- produces insulin to regulate blood glucose levels
Testes (male)- produce testosterone to control puberty and sperm production in males
Ovaries(female)- produce oestrogen, involved in menstrual cycle

Question 4

Difference between hormones and nerves

Answer 4

Nerves have very fast action, act for a short time, act on a precise area
Hormones have slow action, act for a long time, act in a more general way

Question 5

What does the pancreas do when blood glucose levels are too high/low

Answer 5

When glucose is too high, pancreas releases insulin which makes liver take glucose from the blood and turn it into glycogen
When glucose is too low, pancreas releases glucagon which makes liver turn glycogen into glucose and release it into the blood

Question 6

Type 1 Diabetes

Answer 6

Pancreas produces little or no insulin and a persons blood glucose level can rise to a level that can kill them. People with this need insulin therapy which involves several injections of insulin throughout the day, at mealtimes most likely. This makes sure that glucose levels don’t rise too high and it’s removed from the blood when digested

Question 7

Type 2 diabetes

Answer 7

When a person becomes resistant to their own insulin, they produce it but their bodies don’t respond properly to the hormone. This can also cause a persons blood sugar level to rise to a dangerous level. Being overweight can increase your chance of developing type 2 diabetes as obesity is a major risk factor of developing it. It can be controlled be eating a controlled diet with regular exercise

Question 8

4 stages of the mentsrual cycle

Answer 8

1. menstruation starts, uterus lining breaks down for about 4 days
2. uterus lining builds up again from day 4-14 into a thick spongy layer full of blood vessels, ready to receive a fertilised egg
3. egg develops and is released from the ovary at day 14, called ovulation
4. Wall is maintained for 14 days until day 28. If no fertilised egg has landed on the uterus wall by day 28, the lining breaks down and the cycle starts again

Question 9

FSH (Follicle-Stimulating Hormone)

Answer 9

Produced in pituitary gland, causes egg to mature in one of the ovaries in a structure called follicle, stimulates ovaries to produce oestrogen

Question 10

LH (Luteinising Hormone)

Answer 10

Produced by pituitary gland, stimulates the release of an egg at ovulation

Question 11

Oestrogen

Answer 11

Produced in ovaries, causes uterus lining to grow, stimulates release of LH and inhibits release of FSH

Question 12

Progesterone

Answer 12

Produced in ovaries by remains of follicle after ovulation, maintains lining of uterus during second half of the cycle, when level of progesterone falls the lining breaks down, inhibits release of LH and FSH

Question 13

Oestrogen and Progesterone in reducing fertility

Answer 13

Oestrogen can prevent the release of an egg, if oestrogen is taken every day to keep the level permanently high it inhibits production of FSH and egg development will stop and stay stopped
Progesterone stimulates production of thick mucus which prevents any sperm getting through and reaching an egg

Question 14

The combined oral contraceptive pill

Answer 14

Contains porgesterone and oestrogen, over 99% effective, side-effects of nausea and headaches, doesn’t protect against STD’s

Question 15

4 Methods of contraception that use hormones

Answer 15

Contraceptive patch- contains oestrogen(O) and progesterone(P) , lasts one week
Contraceptive implant- contains P is placed under skin of arm and lasts 3years
Contraceptive injection- contains P, lasts 2-3 months
Intrauterine device(IUD)- inserted into uterus to kill sperm and prevent implantation

Question 16

3 barrier contraceptions

Answer 16

Condoms, Diaphragm, Spermicide

Question 17

3 other ways to prevent pregnancy

Answer 17

Sterilisation- cutting or tying fallopian tubes
Natural Methods- timing of menstrual cycle
Abstinence- not have intercourse

Question 18

IVF

Answer 18

Involves collecting eggs from the woman’s ovaries and fertilising them in a lab using the man’s sperm. Can involve ICSI when sperm is injected directly into an egg. Fertilised eggs are grown into embryos in a laboratory incubator then they are transferred to the womans uterus

Question 19

How does adrenaline make the ‘fight or flight’

Answer 19

Triggers mechanisms that increase the supply of oxygen and glucose to cells in the brain and muscles