Renal Conditions Flashcards
What is the main function of the kidneys?
To regulate the extracellular fluid environment which is an important aspect of homeostasis.
What is extracellular fluid?
Fluid which exists outside of the body cells.
What is the role of extracellular fluid?
To supply body cells with nutrients such as oxygen, proteins and amino acids and removing wastes from body cells such as carbon dioxide and urea.
What is the optimum pH for extracellular fluid?
7.35-7.45
Which fluid is a major component of extracellular fluid?
Interstitial fluid
What does interstitial mean?
Between the cells
As well as interstitial fluid, what is the other major component of extracellular fluid?
The plasma in the blood.
At the arteriole end of capillary beds, which three things are squeezed out of the plasma to become interstitial fluid?
Water, electrolytes and nutrients.
At the venous ends of capillary beds which three things return to the plasma?
Water, electrolytes and waste metabolites.
Which term refers to the concentration of osmotically active particles in the plasma?
Serum osmolality
What is the main osmotically active particle in the blood?
Sodium
Which principle acts to keep sodium out of the cells?
The sodium potassium pump.
What are the risks of water entering or leaving the cell by osmosis?
Cell shrinkage or cell enlargement (swelling).
What is the key osmolality range which must be adhered to in order to prevent water from leaving or entering the cells? How is this managed by the kidneys?
275-295mmol/kg.
The kidney regulates this by excreting more or less water.
What is the average blood volume in adults?
3L
Why must blood volume be carefully regulated by the kidneys?
In order to maintain a normal blood pressure to keep blood circulating at an adequate rate.
What is blood volume determined by?
The amount of water and sodium ingested (from the diet) and the amount lost from the body (through urine).
Name three hormones produced by the kidneys?
Erythropoietin, renin and active vitamin D.
Name the 5 key functions of the kidneys:
- Produce hormones (renin, vitamin D and erythropoietin)
- Reglulation of electrolyte levels in the plasma
- Maintain blood volumes
- Maintain blood acid base balance (pH)
- Excretion of waste
- Regulation of the osmolality of the plasma
Name the 4 main componants of the renal system and their primary functions:
The kidneys: filter blood removing waste products
The bladder: stores urine prior to micturation
2x ureters: collect urine from the kidneys and convey it to the bladder
The urethra:takes urine from the bladder to outside the body
Which arteries supply the kidneys?
The renal arteries
The renal arteries are a direct branch of the…
Abdominal aorta
What are the outer and inner parts of the kidneys called?
Outer cortex
Inner medulla
Filtration is carried out by microscopic tubules called:
Nephrons