B.3 Nervous, endocrine, Blood sugar levels Flashcards
Explain how the nervous system deals with a hot rod touching a finger?
Pain/ stimulus is detected by receptors, electrical impulses are sent along sensory neurone CNS. CNS coordanates a response and sends impulses to relay The relay neurone sends electrical impulses to the motor neurone which causes an effector to produce a response
What do sensory and relay neurones do? two different things
Sensory - carries electrical impulses from receptor cells to CNS
Relay - Carries electrical impulses from sensory to motor
What does the motor neurone do?
carries electrical impulses from CNA to effectors
What is a reflex action?
An automatic, involuntary reaction
What are hormones?
Chemical messengers sent in blood
Where are hormones made?
Endocrine glands
What is homeostasis?
Keeping the condition in your body constant
Where is thyroxine produced?
Thyroid gland
Where is adrenaline produced?
Adrenal gland
Where is insulin produced?
Pancreas
Where are oestrogen and progesterone produced?
Ovaries
Where is testosterone produced?
Testes
Compare nerves and hormones speed of communication and method of transportation
Nerves - Very fast speed, travel in electrical impulses along the axon
Hormones - Slower speed, travel through the blood
Compare nerves and hormones duration of response and area targeted?
Nerves - Short acting response, very precise area targeted.
Hormones - Longer acting response and large area targeted
What is negative feedback?
It controls the level of hormones
How does negative feedback work?
When the body detects a change in level of a substance it triggers a response for it to come back to normal levels
What does thyroxine regulate?
Bodies metabolic rate
How does negative feedback keep the right amount of thyroxine in the body?
When thyroxine is higher than normal, TSH is inhibited from the pituatary gland. This reduces the level of thyroxine in the body
When adrenaline is secreted, what does the body do?
Increase rate of ATP production
Increase breathing rate
Increase heart rate
What does metabolic rate mean?
Speed in which chemical reactions occur
How long does the menstrual cycle last?
Around 28 days
Explain the menstrual cycle?
Each month the lining of the uterus thickens ready to recieve an egg, an egg is maturing in one ovary at the same time. Around 14 days later the egg is released. This is called ovulation
What does FSH do?
Causes an egg to mature and causes ovaries to produce oestrogen
What does Oestrogen do?
Causes lining of uterus to build up, causes LH production
As Oestrogen rises what does it inhibit and why?
FSH , so only one egg can be matured
What does LH do?
Releases an egg on day 14
What does Progesterone do?
Maintains uterus lining, inhibits LH and FSH
What does infertile mean?
Unable to reproduce naturally
How can you get pregnant if you are infertile?
IVF
Egg and sperm is fertilised in a lab
What do both progesterone and oestrogen do to prevent pregnancy
Inhibit production of FSH
3 non hormonal contraceptive methods?
IUD
Barriers
Natural
What does natural of non hormonal contraceptive methods mean?
Pulling out
Not having sex
What does barriers of non hormonal contraceptive methods mean?
Condom
Female condom
Diaphragm
Name a hormonal contraceptive methods which use progesterone
Progesterone pill
Name 1 hormonal contraceptive method with involves progesterone and oestrogen
Combined pill
Causes of infertility
Blocked sperm ducks
Not enough sperm being produced
Lack of mature eggs being produced
Failure to release egg from ovaries
What does homeostasis mean?
Maintaining constant blood sugar levels
What food type puts glucose into the body?
carbohydrates
Where are what is excess glucose stored as?
Glycogen, in livers and muscles
If the liver and muscles and full where will glucose be stored?
Lipids ( fats ) in tissues
What monitors and controls blood sugar levels
Pancreas
What hormone do pancreas produce?
Insulin and glucagon
What does insulin do?
Decreases blood sugar levels
How does insulin decrease blood sugar levels?
Insulin makes the liver turn glucose into glycogen
What does glucagon do?
Increases blood sugar levels
How does glucagon increase blood sugar levels?
Makes the liver turn glycogen into glucose
What is type 1 diabetes?
Pancreases produce little insulin, have to get injections
What is type 2 diabetes?
Caused by obesity,becoming resistant to insulin
