B12.1 - 12.5 - Homeostasis In Action✔️ Flashcards
How is urea removed from the body?
Urea is removed by travelling to the kidneys through the bloodstream where it is then filtered allong with salts and water to form urine
What is ammonia?
Ammonia is the waste product when amino acids are broken down in the liver - highly toxic and is converted into urea - less toxic
What is deamination?
The process in which amino acids are broken down into ammonia a highly toxic waste product
What is urea?
Nitrogenous wate product produced when amino acids are broken down and is less toxic then ammonia which it is converted from removed via sweating or as urine - uread is produced when you eat more protein than you need
What can excess urea cause?
Urea is highly toxic and can cause damage to cells
Ways in which water be removed from the body?
-skin
-urine
-faeces
-lungs
Two ways urea can be removed and how?
-removed through sweating along with salts,minreal ions and water
-removed along witch excess water as urine
What waste products does the lungs remove?
-removes carbon dioxide - waste product of aerobic respiration
-removes water
What waste products does the skin remove?
removes minreal ions,salts,water and urea
What waste products are removed with urine?
Excess water,minreal ions and urea
Controlled way of removing excess minreal ions from the body?
Urinating
Uncontrolled way of removing excess minreal ions from the body?
Sweating
What chemical process produced carbon dioxide as a waste product?
Aerobic respiration
Describe how carbon dioxide is transported out the body from where it is produced?
Carbon dioxide transported from tissues like muscles into the bloodstream and then diffuses into the air in the alveoli of your lungs out of the bloodstream - where it is then released when we exhale
Name the organs where urea is made?
Liver - produced by the breakdown of excess amino acids
Why is it important to maintain a water balance?
So cells do not gain or loos water through osmosis which can cause cell damage
How does the body achieve water ballance?
If we are dehydrated kidneys produce less urine - which becomes more concentrated - we also get thirsty - if overhydrated the kidneys will produce large amounts of dilute urine
Which organs removes water and carbon dioxide from the body?
Lungs
Average body temperature?
37 degrees - temperature at which enzymes work best
What does control of core body temperature relie on?
Core body temperature relies on the thermoregulatory centre in the hypothalamus of your brain
How is the thermoregulatory centre in the hypothalamus of your brain adapted for its job?
Contains receptors that are sensitive to temperature changes in the blood flowing through the brain - extra information comes from temperature receptors in the skin
What happens when core body temperature begins to rise?
When core body temperature begins to rise impulses are sent from the thermoregulatroy centre to the body so more energy is transferred to the surroudings to cool you down
What is vasodilation?
When the blood vessels dilate (widen) as a result of the blood vessels muscular walls relaxing - helps to enhance blood flow to areas that are lacking oxygen or other nutrients
How does vasodilation help with temperature control?
Blood vessles widen so skin flushes as there is more blood and more energy is transfered from your skin to the surroundings - cooling you down
Why does the body produce more sweat to cool down?
More sweat from the sweat glands in your skin this extra sweat cools your body down as water evaporates from your skin - transfering more energy from your skin to the surroundings
How does the body keep warm?
-vasoconstrictionin of the blood vessels - they close up which reduces energy transfered by radiation through the surface of the skin
-sweat production is reduced or stopped - less water from sweat evaporates
-skeletal muscles contract and relax rapidly causing you to shiver - muscle contratins require respiration and the energy transfered raises your body temperature
How does the blood vessels vasconstrcting keep you warm?
The blood vessels constrict (close up) reducing the energy transfered by radiation through the surface of the skin
Why are the kidneys important?
Important for homeostasis in the water balance of your body - kidneys conserve water if your short of it (urine little and very concentrated) if you have to much water (lot of urine and will be dilute) - kidneys also control concentration of minreal ions in your body by removing excess minreal ions by excreting them in your urine
How do the kidneys filter the blood?
Glucose,minreal ion,urea and water all move out of the blood into the kidney but the red blood cells and proteins are to big and do not go into the kidney tissues - urine trickles into the bladder to be stored and the glucose is reabsorbed back into the blood by diffusion and active transport - water and dissolved minreal ion are reabsorbed depending on the bodies need for them (selective reabsorption)
What is selective reabsortpion?
The body deciding the amount of water and dissolved minreal ions that are needed to be reabsorbed back into the blood - amount of water reabsorbed into blood is controlled by a sensetie feeback mechanism that makes sure the water balance of your bodily fluids and cells is always kept whithin a narrow range
What hormone is involved in maintaining water balance?
ADH secreted by the pituratary gland when the receptor cells in the brain detect the concentration of solutes in the blood plasma
What are the kidneys made up of?
Millions of tiny tubules - along these tubules that selective reabsorption of water and minreal ions takes place
What happens when the concentration of solutes in the blood becomes to concentrated?
if the concentraion of solutes in the blood becomes to concentrated lots of ADH is released which causes the kidneys tubules to reabsorb more water returning concentration of solutes in the blood to normal
What happens when the concentration of solutes in the blood becomes to dilute?
If the solute concentration in the blood becomes too dilute, less ADH is released into the blood and less water is reabsorbed in the kidneys tubules so you produce a large volume of dilute urine and the blood solute concentration returns back to normal
Two ways of treating kidney failure?
-dialysis - function of kidney is carried out artificialy
-kidney transplant - failed kidney replaced with a healthy one
How does a dialysis machine work?
Carries out the function of the kidneys (cleans the blood) - persons blood leaves their body and flows between partially permeable membranes (on the other side of the partially permeable membranes is the dialysis fluid which contains the same concentration of useful substance as the blood of a healthy persons)treatment of dialysis restores the concentration of these dissolved substances to that of a normal person
Issues with dialysis tratement?
-takes a long time - 8 hours and may have to go to hospital if you dont have a machine at home
-have to recieve treatment severeal times a week - due to the build up of waste substance in the blood
-have to manage diet carefully - have to manage protein intake to keep urea levels low
How is the loss of useful substances prevented during dialysis?
Careful control of the dialysis fluid which contains the same concentration of glucose and minreal ions as the blood of a healthy person which ensures there is no net movment of glucose out of the blood as the dialysis fluid contains normal plasma levels of minreal ions (so any excess minreal ions are removed from the blood by diffusion down a concentration gradient returning levels to normal)
Why does the dialysid fluid contain no urea?
Ensures there is a steep gradient from the blood down to the fluid - ensues most of the urea leaves the blood
What type of transport does dialysis depend on?
Diffusion down concentraion gradient which has to be maintained there is no active transport
What is a problem with kidney transplants?
-risk of rejection - the antigens on the donor organ are different to those of the recipient and the patients immune system starts to attack the donor organ which can result in its destruction
How to reduce risk of rejection with kidney transplants?
-match the antigens of the donor and the recipents - so the “tissue type” is very similar
-take immunosuppressant drugs to supress the immune system which prevents the rejection of the new organ - have to be taken your whole life
Issues with taking immunosuppressant drugs?
-immunosuppressant drugs - prevent the pateient from dealing effectivley with infectious diseases - have to be carefull if they beccome ill
-transplanted organs dont last forever once it fails patient has to return to dialysis machine until another match is found - however scientists grew functioning embryonic kidney tissue from stem cell so there is perhaps a possibility of growing them without antigens
Factors of dialysis?
much more expensive then a transplant and eventually dialysis causes serious damage to the body however it is more widley available and alows people with kidney failure to live an almsot normal life
Factors of a kidney transplant?
You can eat and drink what you want and have an almost normal life however the disadvantages of kidney transplants are the risk of rejection and you have to take immunosuppressant drugs every day for your life an you need frequent check ups
