7.2 The liver and skin

how is protein generally stored/minimally lost

proteins typically arent used in energy reactions

excess proteins cant be stored so they have to be removed

small amounts are lost via urine, skin, hair, and fingernails

how does the liver effect proteins

it can metabolize them for energy

deamination removes amino group using enzymes

then converted into ammonia and urea

remaining amino acid converted into carbohydrate to be broken down for energy

what is the amino acid breakdown equation

amino acid + oxygen → carbohydrate + ammonia

what happens to the leftover ammonia

it is very toxic so the liver rapidly converts it into urea to be excreted in urine

what is the ammonia to urea equation

energy + carbon dioxide + ammonia → urea + water

what are other functions of the liver

detoxifies alcohol and antibiotics

deactivates hormones to be excreted through kidneys

breaks down haemoglobin into bile pigments

what does the skin do

protects body

regulates temperature

secretes sweat

what is the composition of sweat

sodium chloride, lactic acid, and urea, dissolved in water

how do sweat glands excrete sweat

duct carries sweat to hair follicle or pore

cells surrounding glands contract and squeeze sweat out to surface