Keeping Internal Conditions Constant Flashcards
What is homeostasis?
The maintenance of constant internal body conditions
What body conditions must be controlled for homeostasis?
- Temerature
- Blood glucose level
- Water levels
- Ion content levels
- Levels of waste products
What waste products are removed by the body and how?
- CO2 produced by respiration is removed via the lungs when we breathe out
- Urea, produced in the liver from the breakdown of amino acids, is removed by the kindeys in urine and temporarily stored in the bladder
How do water and mineral ions enter the body?
When we eat and drink
What could happen if the water or ion content of the body is wrong?
To much water may move into or out of the cells
This could destroy or damage the cells
What does the kindey do?
Filters the blood, excereting substances you do not want and keeping those your body needs
How do the kindeys produce urine?
- First filtering the blood
- Reabsorbing all the sugar
- Reabsorbing the dissolves ions needed by the body
- Reabsorbing as much water as the body needs
- Releasing urea, excess ions, and excess water in the urine
Where does the urine go before it exits the body?
It is temporarily stored in the bladder
What is the ureter?
Tube through which urine passes from the kindey to the bladder
What is the urethra?
Tube through which urine passes to the outside of the body
What are the names of the blood vessels that supply blood to the kindeys and take it away?
The aorta and renal artery
The renal vein and vena cava
What does the renal artery and renal vein do?
Renal artery brings blood containing urea + other susbstances in solution to the kidney
Renal vein carries blood away after these have been removed
Why don’t we constantly piss all the time?
There’s a ring of at the bottom of the bladder which controls when it opens and closes
What is dialysis?
The process of cleaning blood through a dialysis machine when a person’s kindeys don’t work properly or have failed
How does dialysis work?
- The dialysis fluid contains the same concentration of useful substances (ions + sugars) as the patient’s blood
- This means that they do not diffuse out of the patient’s blood so do not need to be reabsorbed
- Urea diffuses out from the blood into the fluid
- Dialysis restores the concentration of substances in the blood back to normal, but needs to be carries out at regular intervals
If a person has a kindey transplant, what will this mean?
They will no longer require further dialysis
Draw and label a diagram of the process of dialysis
The dialysis machine has a partially permiable membrane
Blood cells and proteins are too large to pass through this