Urinary System Flashcards
What is the urinary system of mammals comprised of?
- pair of kidneys
- ureters
- urinary bladder
- urethra
What type of organ is the kidney?
- parenchymal organ
- highly vascular organ
What are the tubular organs of the urinary system?
- ureter
- urinary bladder
- urethra
What are the different functions of kidneys?
- filter blood
- reabsorb water
- reabsorb electrolytes
- eliminate metabolic wastes (as urine)
- hormone production
How do kidneys eliminate metabolic waste?
- as urine
- through the ureter which leads to the bladder
What biologically active molecules does the kidney produce? State their names.
hormones:
- erythropoietin
- renin
- angiotensin II
What function are the kidneys associated with?
the excretory function
Why are kidneys classified as “highly vascular organs”?
they recieve 20-25% of the cardiac output
(large volume of blood continuously rushes through the kidneys).
What is the name of the kidneys functional component?
the nephron
What is initially seperated from the blood in the kidneys (nephrons)? What does it form?
plasma is seperated from cells and large proteins forming primary urine.
What happens to primary urine once it is formed?
Primary urine passes through tubules where it is additionally filtrated.
What is formed from primary urine, after it is filtered? What is it composed of?
final urine:
- water
- electrolytes
- many waste products: urea, uric acid, and creatonin.
What is reabsorbed in the kidneys? What is it called? Where does it go?
- glucose
- ions
- small molecules
reabsorbed back to the blood
“clean blood” exits the kidney
What is erythropoietin?
- hormone
- associated with deoxia
- decreased level of oxygen in the cells cellular level
Why is erythropoietin produced?
- sufficiently compensate normal red blood cell turnover
- (increase the number of erythrocytes inorder to carry more oxygen)
What is renin? What is its function?
- regulates the renin-angiotensin-aldosterone system (RAAS)
- mediates the volume of extracellular fluids
- regulating arterial pressure
Explain the structure of the kidney.
- tough fibrous capsule (irregular dense connective tissue)
- very little connective tissue
- cortex (granular)
- medullar (striated)
organised into lobes
- pyramidal structure
What do the kidneys have as an outer layer? What is it composed of? What is its function?
tough fibrous capsule:
- made of irregular dense connective tissue
- for protection
How much connective tissue is present between the kidney nephrons?
- very little connective tissue
What is the kidneys outer region called? What is its appearance? Why?
cortex:
- granular
- full of ovoid filtration units
Why is the cortex granular?
it is full of ovoid filtration units
What is the inner region of the kidney called? What type of appearance does it have?
medulla:
- striated appearance
What is the kidney organised into? What are their structures? Explain their composition.
organised into lobes:
- pyramidal structure
- outer portion: cortex
- inner portion: medulla
What is an exceptional feature of the kidney? What does this further mean?
The tough fibrous capsule is not branched!
- does not have branches or trabecules going deeper into the organs lobes/lobules
this means that there are very little stroma components deeper to the capsule.
–> most of the organ is composed of PARENCHYMA