b12 Flashcards
What monitors and controls body temperature?
Thermoregulatory centre in the brain
How is body temperature detected?
Receptors in thermoregulatory centre measure blood temperature; Receptors in skin send impulses to thermoregulatory centre
What happens if body temperature is too high?
Blood vessels dilate, vasodilation; Sweat glands make sweat
What happens if body temperature is too low?
Blood vessels constrict, vasoconstriction; Sweating stops; Skeletal muscles contract - shivering
How does water leave the body?
Via lungs during exhalation - uncontrolled; Via skin in sweat - uncontrolled; Via kidneys in urine - controlled
How do ions leave the body?
Via skin in sweat - uncontrolled; Via kidneys in urine - controlled
How does urea leave the body?
Via skin in sweat - uncontrolled; Via kidneys in urine - controlled
Why does osmotic balance need to be maintained?
So cells can work efficiently
Where does urea come from?
Excess protein → amino acids → deamination → ammonia → urea
Where is urea produced?
The liver
List the processes that occur in the kidney
Filtration, selective reabsorption and excretion
Which substances are reabsorbed?
Some water and ions; All glucose
Which hormone controls reabsorption of water and where is it made?
ADH - pituitary gland
When is ADH released?
When blood is too concentrated
What effect does ADH have?
Causes more water to be reabsorbed by the tubules
How can we treat people with kidney failure?
Dialysis or transplants
