Essential Ion and Compound Balance and Homeostasis - Renal Flash Cards - Anatomy & Physiology

From WikiVet English

(diff) ← Older revision | Approved revision (diff) | Latest revision (diff) | Newer revision → (diff)

Jump to navigation Jump to search

Use the mouse to highlight the answers. They are written in white

Question Answer Link
What the effects of varying sodium concentration within the body?
  • Too low
    • Water and ECF volumes fall
    • Sodium dependant transporters are disturbed
  • Too High
    • Water and ECF volume increases
    • Sodium dependant transporters are disturbed
Why is sodium not regulated on the basis of plasma concentration?
  • Water follows sodium. Therefore volume notconcentration alter
  • The hormonal controllers affect sodium concentration and ECF concentration
  • ADH and the thirst response dilute any increase in sodium by increasing ECF volume
What is "salt hunger"? It's where an animal with low body salt concentrations actually craves salt Link
What are the three major sources of potassium?
  • Diffusion from the small intestine
  • Active transport from the colon
  • Recovered from cellular breakdown
By which three methods is potassium homeostasis managed? Which of these make up the chronic and which the acute response
  • Cellular translocation - Acute
  • Renal excretion - 90% of chronic
  • GI excretion - 10% of chronic
Which two things control the acute response and how do they do it?
  • Insulin
  • Activation of beta2 adrenoreceptors
  • Work by increasing the activity of Na+ / K+ ATPases causing sodium efflux and potassium influx
Which hormone is the main regulator of potassium?? Aldosterone Link
In which two regions of the nephron is H+ secreted?
  • Proximal tubule
  • Collecting duct
What role do buffers play with regard to excreting hydrogen ions? Once all bicarbonate has been reabsorbed they combine with residual excess hydrogen allowing it to be excreted without the loss of bicarbonate and without making the urine very acidic. Link
In ruminants fed low nitrogen diets more urea is reabsorbed. Why? It is transported to the rumen and converted to microbial protein Link