The Kidney - Osmoregulation Flashcards
What does ADH stand for
Anti-diuretic hormone
What controls water potential
Hypothalamus
Osmoreceptor neurones
Antierior pituitary glans
ADH
WHat process controls water potential of body fluids
Osmoregulation
What monitors water potential of the blood
Osmoreceptors
How do osmoreceptors control water potential (detecting change)
Osmoreceptors found in the hypothalamus
Detect a decrease in water potential of the blood, verve impulses are sent along sensory neurones to the posterior pituitary gland
How do osmoreceptors control water potential of the blood (after detecting the change)
Nerve impulses stimulate the posterior pituitary gland to release antidiuretic hormone (ADH)
ADH enter the blood and travel throughout the body
What does ADH do to control water potential
ADH is released in the posterior pituitary gland which causes the kidneys to reabsorb more water to reduce the loss of water in the urine
Is osmoregulation positive or negative feedback
Negative
How does osmoregulation detect change detail
1) Osmo-receptor cells in hypothalamus lose water by osmosis and shrink (osmosis is high to low concentration of water, high water potential in blood causes water in cells to leave via osmosis)
2) This stimulated neuro-secretory cells to produce more ADH from the posterior pituitary gland
How does ADH control water potential in detail
1) ADH travels to kidney and acts on collecting ducts in the kidney that increases aquaporins that are inserted into the cell surface membrane in the collecting duct so water can enter the bloodstream
2) Urine is therefore produced with a lesser water potential
Negative feedback of water potential in blood when water potential is high
1) Hypothalamus detects high blood water potential
2) Pituitary secretes less ADH
3) Aquaporin channels close
4) Less water is reabsorbed from urine
5) Water potential brought back up to normal
Negative feedback of water potential in blood when too low
1) Hypothalamus detects low blood water potential
2) Pituitary secretes more ADH
3) ADH increases production of cAMP
4) cAMP increases the number of aquaporins
5) More water is reabsorbed from the urine
6) Water potential of blood is brought back up to normal
What molecules affect blood glucose concentration
Insulin
Glucagon
Adrenaline
How does insulin, glucagon and adrenaline affects blood glucose concentration control
Insulin = decereases blood conc of glucose if too high
Glucagon = increases
Adrenaline = increases
How does insulin reduce glucose in blood
Convert glucose into glycogen
Put it in muscles
Break down glucose and use it
Make it into fats