B3 Homeostasis

Question 1

Where is urea produced?

Answer 1

Urea is produced by the liver and excreted by the kidneys

Question 2

Where does “filtration” and “re absorption” take place in the kidneys?

Answer 2

Filtration occurs in the glomerulus, while the majority of re absorption occurs in the proximal convoluted tubule of the nephron.

Question 3

What organ stores urine?

Answer 3

Kidneys

Question 4

Explain why protein is not found in the urine of a healthy person

Answer 4

• Protein is too large
• Cannot pass through filter
• Cant leave the blood

Question 5

Describe the process of dialysis

Answer 5

Dialysis has to be done regularly to keep the concentrations of dissolved substances in the blood at normal levels, and to remove waste substances.
In a dialysis machines, the persons blood flows alongside a selectively permeable barrier surrounded by dialysis fluid.
-Three times a week, 3-4 hours

Question 6

2 advantages and 1 disadvantages of a kidney transplant rather than dialysis treatment

Answer 6

A - Patients can lead a more normal life without having to watch what they eat and drink
A - Cheaper for the NHS overall
D- Shortage of organ donors

Question 7

Where is body temperature controlled?

Answer 7

The hypothalamus is the processing centre in the brain that controls body temperature

Question 8

Explain the effect of shivering and sweating on the core body temperature

Answer 8

Sweat is produced by sweat glands and evaporates from the skin, which removes heat.
When you’re cold you shiver which requires respiration, which releases some energy to warm the body

Question 9

State which organ controls blood glucose concentration

Answer 9

Insulin is a hormone produced by the pancreas that regulates glucose levels in the blood.

Question 10

Give one way other than using insulin of treating diabetes

Answer 10

Tablets and medication

Regular exercise