Osmoregulation Flashcards
(19 cards)
What does osmoregulation mean?
Control of water and salt levels in the body.
What does the loop of henle do?
Draws more water out of the filtrate in the nephron
Where are sodium and potassium ions actively transported out of?
Thick ascending limb into the tissues fluid
What causes a high concentration of sodium and potassium ions in the tissue fluid in medulla?
Water cannot follow by osmosis out of the thick ascending limb into
What does an increase of ions cause?
The tissue fluid draws more water out of the descending limb and collecting duct by osmosis, which is then removed by the capillary network
What is the capillary network?
Blood
What is homeostasis?
Regulation of a constant internal environment
What is osmoregulation regulated by?
Hypothalamus and release of ADH
What is ADH?
Antidiuretic hormone
Where is ADH secreted from?
Pituitary gland
What does antidiuretic mean?
Reducing urine output/production by increasing re absorption of water (in kidney)
What happens if the hypothalamus detects the water potential of the blood?
The less water there is in the blood the more ADH is released
What does it mean that ADH is more permeable to water?
Water is reabsorbed by osmosis
If the pituitary gland releases more ADH there would be … water in the urine?
Less
If there was less water in the urine it would make the urine … concentrated.
More
How does drinking alcohol affect urine production?
- alcohol inhibits ADH production
- less water reabsorbed in kidneys
- increase urine production, lead to higher volume
What is negative feedback?
Regulatory mechanism in which the stimulus causing the opposite effect to maintain balance in the system and bring back to normal
Why is osmoregulation an example of negative feedback?
When water levels in blood drop, ADH increases and retains more water to normal level, when water levels increase the amount of ADH released decreases and allows more water to be lost in urine - bringing the blood water levels back to normal
If too much ADH is released what happens to blood pressure?
More water in the blood means high blood blood volume and higher blood pressure
