B5- Homeostasis And Response Flashcards
What are control systems made up of?
Receptors
Coordination centres
Effectors
How does a control system work?
Receptors detect a change in environment (stimulus)
They send this to the coordination centre and then it processes the information and organises a response
Effectors then produce a response
What is the CNS?
Consists of the brain and spinal cord. It is connected to the body by sensory and motor neurones
What are motor neurones?
They carry electrical impulses FROM the CNS to the effectors
What are sensory neurones?
They carry information as electrical impulses FROM receptors TO the the CNS
What are effectors?
They respond to electrical impulses and bring a change
What are receptors?
They detect stimuli (changes in the environment) e.g ears detect sound
Which gland in the body monitors and controls blood glucose concentration?
the pancreas
Which hormone is produced when blood glucose concentration becomes too high?
insulin
Where does the glucose in the blood go if the blood glucose level is too high?
in the liver
What happens to the glucose when it reaches the liver?
it is stored into glycogen
Why do people have type 1 diabetes?
because they produce little or no insulin
How can type 1 diabetes be treated?
By insulin injections
Give two treatments that a doctor would recommend for type 2 diabetes?
regular exercise
healthy diet
Give a risk factor for type 2 diabetes
being overweight
What are hormones?
They are chemicals released by glands which are released directly into the blood stream
Where is the pituitary gland?
In the brain
what is the role of the pituitary gland?
They release many hormones to regulate body conditios
what does the thyroid gland do?
it produces thyroxine and regulates metabolism, heart rate and temperature
where is the thyroid gland?
in the throat
What does the adrenal gland do?
it produces adrenaline and triggers the flight or fight response
Where is the pancreas?
underneath the stomach
what is the role of the pancreas?
it produces insulin and regulates the blood glucose levels
What is the role of the testes?
it produces testosterone and it controls sperm production and puberty in males
what is the role of the ovaries?
it produces oestrogen and is involved in the menstruation cycle
what are the differences between nerves and hormones?
nerves: very fast action, act for a very short time, act on a very precise area
hormones: slower action, act for a long time, act in a more general way
what is the main sex hormone in men?
testosterone
where is the main sex hormone produced?
in the testes
What is the role of the main sex hormone in men?
to produce sperm
What is the name of the main female reproductive hormone produced in the ovary?
oestrogen
what is the name of the process by which eggs are released from the ovary?
Ovulation
how often is an egg released from an ovary?
every 28 days
name the hormone that causes the release of an egg
LH
what is the role of FSH?
causes an egg to mature in one of the ovaries
what is the role of LH
causes the release of an egg (ovulation)
what is the role of oestrogen and progesterone?
these hormones are involved in the growth and maintenance of the uterus lining
what happens when the glucose concentration in the blood becomes too high?
insulin is produced by the pancreas and glucose moves into the liver and muscle cells to be stored as glycogen
suggest how the progesterone level changes before a woman starts to bleed
the progesterone level will fall. progesterone helps to maintain the uterus lining so when the level drops, the lining breaks down and the woman will bleed
what is the name of two hormonal forms of contraception?
contraceptive injection and the contraceptive patch
how is an oral contraceptive taken into the body?
as a tablet taken by the mouth
how do oral contraceptives containing multiple hormones prevent pregnancy?
the hormones stop FSH production
the contraceptive implant is inserted under the skin of the arm. Which hormone does it release?
progesterone
how does the hormone released by the contraceptive implant prevent pregnancy?
it stops the eggs maturing
suggest one advantage of the contraceptive implant over an oral contraceptive
A woman doesnt have to think about the implant everyday and the chances of becoming pregnant remain low
How do barrier methods of contraception prevent a woman from becoming pregnant?
they stop sperm from getting to an egg
name a barrier method of contraception that protects against STD’S
condoms
some barrier methods need to be used with spermicides. explain how spermicides help to prevent pregnancy
they kill sperm, preventing the egg from being fertilised
a couple not wishing to have children do not want to use any form of contraception. suggest how they should avoid pregnancy
they should not have intercourse when the woman is at the point in her menstruation cycle when she is most likely to become pregnant
