hormones and kidney Flashcards
how does your body warm up
1) your temperature receptors detect that core body temperature is too high
2) the thermoregulatory centre acts as a coordination centre, it receives information from the temperature receptors and triggers the effectors automatically
3) the effectors e.g sweat glands produce a response and counteract the change
how does your body cool down
1) temperature receptors detect that core body temperature is too low
2) the thermoregulatory centre acts as a coordination centre, it receives information from the temperature receptors and triggers the effectors automatically
3) effectors e.g muscles produce a response and counteract the change
how do your effectors produce a more sensitive response to the body’s temperature
- some effects work antagonistically and will work at the same time to achieve a very precise temperature, this mechanism allows a more sensitve response
how does the body keep the core body temp constant
by balancing the energy gained and lost
where is the thermoregulatory centre found
in the brain
what does the thermoregulatory centre contain
receptors that are sensitive to the temperature of the blood flowing through the brain
what does the thermoregulatory centre do
- the thermoregulatory centre acts as a coordination centre, it receives information from the temperature receptors of the brain and skin giving information about the body temperature
what happens to your body when your too hot
1) sweat is produced by the sweat glands and evaporates from the skin, this transfers energy to the environment
2) the blood vessels supplying the skin dilate so more blood flows to the surface of the skin, this is called vasodilation, and this helps transfer energy from the skin to the environment
what happens to the body when you are cold
1) hairs stand up to trap an insulating layer of air
2) no sweat is produced
3) blood vessels supplying skin capillaries constrict to close off the skins blood supply, this is called vasoconstriction
4) when youre cold you shiver by muscles contracting automatically, this needs respiration which transfers some energy to warm up the body
what are hormones
chemical molecules released directly into the blood
what do hormones do
- control things in organs and cells that need constant adjustment
- are carried in the blood to other parts of the body and only affect particular cells in target organs
where are hormones produced
in glands called endocrine glands
examples of endocrine glands that make up the endocrine system
- pituitary gland - this produces many hormones that regulate body conditions, these hormones also affect other glands causing them to produce hormones that bring about a change (also known as master gland)
- thyroid - this produces thyroxine which involves regulating things such as the rate of metabolism, heart rate and temp
- adrenal gland - produces adrenaline which is used to prepare the body for a fight or flight response
- ovaries - produce oestrogen - which is involved in the menstrual cycle
- pancreas - produces insulin which is used to regulate the blood glucose level
examples of endocrine glands that make up the endocrine system
- pituitary gland - this produces many hormones that regulate body conditions, these hormones also affect other glands causing them to produce hormones that bring about a change (also known as master gland)
- thyroid - this produces thyroxine which involves regulating things such as the rate of metabolism, heart rate and temp
- adrenal gland - produces adrenaline which is used to prepare the body for a fight or flight response
- ovaries - produce oestrogen - which is involved in the menstrual cycle
- pancreas - produces insulin which is used to regulate the blood glucose level
- testes - produces testosterone which controls puberty and sperm production in males
difference between hormones and nerves
HORMONES
- slow action
- act for a long time
- act in a more general way
NERVES
- very fast action
- acts for a short time
- acts on a very precise area
what happens when your blood glucose is too high
1) insulin is secreted by the pancreas
2) insulin travels in the bloodstream all around the body and triggers body cells to take up glucose from the blood, liver and muscle cells to convert the glucose into glycogen to store excess glucose
3) as the glucose has now been taken out of the blood and stored the concentration of glucose in the blood returns to its normal level
what happens when the blood glucose level is too low
1) the pancreas releases the hormone glucagon into the bloodstream
2) glucagon triggers liver cells to convert glycogen stores back to glucose
3) the glucose is then released into the blood
4) this causes the blood glucose concentration to return back to normal
what is diabetes
a condition that affects your ability to control your blood sugar level
what is type 1 diabetes
- this is where the pancreas produce little or no insulin
- this causes the blood glucose concentration to rises and stay at a high level as the pancreas does not produce a sufficient amount of insulin
how do you treat type 1 diabetes
- they have insulin therapy - this is involves them being injected with insulin throughout the day, especially at meal times to make sure that glucose is removed from the blood quickly once the food has been digested, stopping the level from getting to high - the amount of insulin injected depends on the persons diet and how active they are
- they are also encouraged to limit their intake of food rich in simple carbohydrates - which causes glucose levels to rise rapidly and to do regular exercise - which removes excess glucose from blood
symptoms of type 1 diabetes
- you urinate a lot as the kidney has to secrete glucose into the urine making you more thirsty
- feel very fatigue and tired as not enough glucose is sent to the cells
- you start to lose weight as the body starts to break down fats and proteins as fuel
what is type 2 diabetes
when a person becomes resistant to their own insulin causing the blood glucose level to rise too high
how do you treat type 2 diabetes
- having a carbohydrate controlled diet to stop the blood glucose concentration from rising to high
- regular exercise
what causes type 2 diabetes
- genetics
- obesity
what does the kidney do
it makes urine by taking waste products out of the blood to filter it
useful substances passed through the kidney are absorbed back into the blood from the kidney through the process of selective reabsorption
what substances are removed from the body in urine
- urea
- ions
- water
why does urea need to be removed from the blood
- proteins cant be stored by the body so any excess amino acids are converted into fats and carbohydrates which can be stored, this occurs in the liver and is called deamination
- ammonia is a waste product in deamination, which is toxic so it’s converted to urea in the liver, urea is then transported to the kidneys where it’s filtered out of the blood and excreted from the body in urine
why does ions need to removed from the blood
- ions are taken into the body in food and then absorbed into the blood
- if the ion content is wrong this could disrupt the balance between ions and water, meaning too much or too little water is drawn into the cell by osmosis, having the wrong amount of water can damage cells or mean they don’t work as well
- some ions are lost in sweat, however this amount is not regulated so the right balance of ions in the body must be maintained by the kidneys.
- the right amount of ions is reabsorbed into the blood after filtration and the rest is removed from the body into the urine
why does water need to be removed from the blood
- we lose water from the skin in sweat and from the lungs when breathing out this means that water has to be constantly balanced
- we cant control how much water we lose so the amount of water is balanced by the amount we consume and the amount removed by the kidneys in urine
what is the concentration of urine controlled by
a hormone called anti-diuretic hormone, ADH
where is ADH made
in the pituitary gland
what happens if the water content too high
1) receptors in the brain detect that the blood plasma is too dilute
2) the coordination centre in the brain receives this info and coordinates a response
3) the pituitary gland releases less ADH so less water is reabsorbed from the kidney tubules, so you produce the volume or dilute urine and the water concentration returns back to normal
what happens if the water content is low
1) receptors in the brain detect that the blood plasma is too concentrated
2) the coordination centre in the brain receives this info and coordinates a response
3) the pituitary gland releases lots of ADH so more water is reabsorbed from the kidney tubules, so you produce a small volume of concentrated urine and the water concentration returns back to normal
what is negative feedback
an automatic control systems to keep your internal environment stable
how does negative feedback work
1) receptor detects a stimulus
2) the coordination centre receives and processes the info and then organises a response
3) effector produces a response that counteracts the change and restores the optimum level
what happens if your kidneys dont work properly
- waste substances start to build up in the blood and you lose your ability to control the levels and ions in the body and this eventually leads to death