Excretory System Flashcards
What is Osmoregulation?
The importance of maintaining water balance inside the cell versus outside of the cell.
How does Osmoregulation relate to homeostasis?
Osmoregulation is maintain the homeostasis of the organisms water content.
Why is the breakdown of proteins potentially toxic to the human body?
The breakdown of proteins are toxic because ammonia is converted i the process. Ammonia is highly toxic, even in low concentrations. Therefore, it is matched with HCO3- to create urea.
What is the role of the liver and kidneys in ensuring that the toxid byproducts do not build up to lethal levels?
The liver matches ammonia with HCO3- to create urea. The kidneys clean blood and sends waste through the ureter to the bladder to be eliminated.
What are the three roles of the kidneys?
- Balances blood pH - Maintains the bodies H2O balance - Excretion of wastes and toxins
What is filteration?
This is the 1st step of urine formation. It occurs as body fluids move from the blood into the bowmans capsule.
What is reabsorption?
This is the 2nd step of urine formation. It transfers essential solutions and H2O from the nephron back into the blood.
What is secretion?
This is 3rd steps of urine formation. It transfers materials (often toxins) from the blood back into the nephron mainl by active transport.
Draw and label a diagram of the kidney making sure to include the location and orientation of nephrons.
Why is urine referred to as hypoosmotic? (Come back to this bc it might be wrong)
Because it has a lower osmotic pressure than a surrounding fluid under comparison.
What are the three steps of urine formation?
- Filteration - Reabsorption - Secretion
Draw a Nephron:
- Label all important regions
- Explain on your diagram what happens at the Bowman’s Capsule
- Explain what happens in the proximal tubule - what substances are moving where and why?
- Explain the descending loop of Henle - what is the importance of the permeability of the membrane and the salt concentration of the external environment?
- What occurs in the distal convoluted tubule?
- What occurs in the collection duct?
- Picture
- At the bowman’s capsule pressure pushes stuff from the capillaries into the bowman’s capsule. The Bowman’s capsule then pushes the now called filtrates into the first section of the nephron; the proximal tubule.
- The proximal tubule uses osmosis to absorb the good stuff needed for the body.
- Salt has a higher concentration
What is the role of antidiuretic hormone (ADH)?
Increases permeability of distal tubule to H2O.
In what portion of the nephron does ADH act and what are the consequences?
It acts in the distal tubule and consiquences of no ADH is less H2O absorption, therefore, causing dehydration. Can be cause by Alcohol and Caffeine.
How does the the kidney help to regulate blood pH?
H+ ions are actively transported into the filtrate in order to control blood pH. This slows or increases until blood pH returns to normal.
