Homeostasis - created from Mind Map

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Water Content - (Osmoregulation)

Temperature

Blood sugar concentration

Controlled via osmosis

Alcohol interferes with both

Regulation takes place in the kidneys

When the water content is higher outside the cell than in, water enters the cell by osmosis

This causes the cell to rupture.

Under the control of the anti-diuretic hormone (ADH)

Too Low

Filter blood and regulate water content

Concentration of salt in the body becomes high

Detected by Osmoreceptor cells found in the hypothalamus

Stimulates thirst sensors in the brain

Stimulates pituitary gland to release ADH into the blood

Carried to the kidneys

If temperature gets too high, heat sensitive cell detect this.

Inside cells, if the temperature exceeds 40c, enzymes become denatured

Regulated by the hypothalamus and pituitary gland

If temperature gets too low

Alcohol interferes with both

The Capillaries dilate (vasodilation) which results in an increased blood flow to the skin.

Sweat glands produce sweat to cool skin and blood

This is what causes blushing and redness

Heat is then lost to the environment

Cannot be reformed, and cell dies

Hypothalamus measures the temperature of the blood flowing through it

Initiates responses to combat

Rapid contraction of muscles generates heat

Goosebumps/hairs stand on end (Piloerection)

Capillaries narrow (Vasoconstriction) which results in decreased blood flow to the skin

Shivering

Layer of air is trapped above the surface of the skin

Forms insulator and prevents heat loss

Warm blood is kept deep within body so heat loss to the outside is minimised

Why skin can look blue in the cold

Become easily dehydrated

Don't respond properly to temperature changes

Too much sugar is drawn out of the cell

Insulin regulates sugar concentration

Too high

Too low

Causes it to collapse

Pancreas has receptors that detect the rise in blood glucose levels

Then releases insulin into the blood

Insulin is a hormone

Removes sugar from the blood

Converts glucose to glycogen

Promotes the uptake of glucose by muscles for respiration

Pancreas detects fall in glucose levels

Releases glucagon into the bloodstream

Activates enzymes inside the tissues especially the liver and muscles

Converts glycogen to glucose