Chapter 13 Flashcards
What is formed in the liver from excess amino acids?
urea
What is is excreted through the lungs?
carbon dioxide
What do kidneys excrete?
urea and excess water and salts
Explain that the volume and concentration of urine produced is affected by water intake, temperature and exercise
If you exercised a lot, did not drink a lot of water or you are in a very hot environment then the kidneys will take back as much as they can so you produce a more concentrated urine and conserve water. if you have not been exercising, did drink a lot of water or you are in a cold environment, you release more water and produce more dilute urine.
Identify on drawings, diagrams and images, the ureters, bladder and urethra
sure
Describe the role of the liver in the assimilation of amino acids by converting them to proteins, including plasma proteins, e.g. fibrinogen
Amino acids can not be stored so the liver breaks down amino acids not required for making proteins. Each amino acid molecule is broken down into two by deamination. One molecule is converted to carbohydrates and fats and the ammonia molecule (deamination is the removal of the nitrogen part /amino group) combines with CO2 to form urea. **
deamination
the removal of the nitrogen-containing part of amino acids to form urea
Explain the need for excretion
Excretion is needed to remove substances such as urea and carbon dioxide as their buildup is toxic and can destroy tissue.
Outline the structure of the kidney
the cortex, medulla and ureter
Outline the structure and functioning of a kidney tubule
The glomerulus in a kidney tubule is responsible for the filtration from the blood of water, glucose, urea and salts. The tubule is responsible for the reabsorption of all of the glucose, most of the water and some salts back into the blood. Leading to the concentration of urea in the urine as well as loss of excess water and salts. The urine is removed as it passes down the ureter and into the bladder.
Explain dialysis in terms of salt balance, the maintenance of glucose concentration and the removal of urea
The solution used in dialysis is called dialysate. The fresh dialysate entering the dialyser does not contain urea. This means that urea is transported by diffusion from the blood into the dialysate down a concentration gradient. The fresh dialysate contains glucose and salts at the correct blood concentrations. Diffusion of these substances from the blood only occurs if their concentrations are too high.
Describe the use of dialysis in kidney machines
Kidney dialysis is a method of artificially filtering the blood in order to remove excess urea, water, salts, glucose and other waste products. Dialysis involves the use of a dialysis machine
Discuss the advantages and disadvantages of
kidney transplants, compared with dialysis
Ad:
- a person can turn to full health while a person needs to go through kidney dialysis 3 times a week. This can effect their work, exercise and spend time with friends and family.
- dialysis does not work as efficiently as a healthy transplanted kidney, so it has long-term health consequences.
Disad:
- Finding a suitable donor kidney may take a very long time.
- The patient’s body can sometimes reject the transplanted kidney. This occurs because the immune system recognises the new kidney as non-self and mounts an immune response against it.
- Immunosuppressant drugs must be taken to prevent the rejection of the new kidney, but these may have side effects.
- The operation is expensive and recovery may be slow.
