B12 Homeostasis In Action Flashcards
12.1 How is the body temperature monitored and controlled?
It is monitored and controlled by the thermoregulatory centre in the brain. The thermoregulatory centre contains receptors sensitive to the temperature in the blood.
12.1 What does the skin do to control the body temperature?
The skin contains temperature receptors and sends nerve impulses to the thermoregulatory centre.
12.1 What happens when the body temperature is high?
The blood vessels dilate (vasodilation) and sweat is produced from the sweat glands. Both cause a transfer of energy from the skin to the environment.
12.1 What happens if the body temperature is too low?
Blood vessels constrict (vasoconstriction) and sweating stops, reducing the transfer of energy to the environment.
12.1 How do skeletal muscles raise the temperature?
They contract (shiver) and the exothermic reactions of respiration needed for muscle contraction raise the temperature.
12.2 How is water loss in the body where you have no control?
- Water leaves the lungs every time you exhale
- Water, mineral ions, and urea are lost through the skin through sweat.
12.2 What are the two poisonous substances in your body?
Carbon dioxide and urea
12.2 Why does Carbon Dioxide need to be removed/maintained?
- It produces an acidic soluton
- This would affect the working of all the enzymes in the cells.
12.2 How does the body remove Carbon Dioxide in your body?
- It diffuses out of your cells into your blood down a concentration gradient.
- It diffuses from the blood into the air in the alveoli of your lungs.
- The it is removed when you exhale.
12.2 Why does Urea need to be removed/maintained?
The Urea passes from the liver cells into your blood. Urea is poisonous and if levels build up in your body which causes damage to your cells.
12.2 How does your body remove Urea.
It is filtered out of your body by your kidneys and then passed out of your body in the urine passed out of your body in the urine produced by kidneys, along with any excess water and salt.
12.2 How is water and mineral ions loss in the body when you control it?
Urea, along excess water and mineral ions, is removed via the kidneys in the urine.
12.3 What is the function of kidneys?
- Your kidneys are important for homeostasis in water and salt (mineral ions) balance of your body.
12.3 What does a healthy kidney do?
- It produces urine by filtering the blood. It then reabsorbs all of the glucose, plus any mineral ions and water needed by your body.
- Anything not needed is removed by the urine.
12.3 How is water in the blood maintained?
It is maintained by the hormone ADH, which changes the amount pf water reabsorbed by the kidney tubules.
