Lecture 16 Flashcards
What are the four components of the urinary system?
- kidney
- ureter
- bladder
- urethra
How much do kidneys weigh each?
150g
How much blood flow do the kidneys receive?
25%
What is the purpose of the kidney?
to regulate the composition and volume of body fluids
What does the kidney do?
it filters the blood and controlling what substances and how much of the substances, along with water are excreted from the body
What are 5 functions of the kidney?
- regulation of water and ion balance, body pH
- excretion of metabolic wastes
- excretion of foreign chemicals
- endocrine functions (calcitriol, EPO, renin)
- gluconeogenesis
What are some metabolic wastes excreted by the kidney?
- when nucleic acids are broken down to uric acid
- creatinine from muscle
- when urea is broken down to amino acids
Give an example of foreign chemicals that are excreted by the kidneys
drugs
What is the purpose of calcitriol?
for the absorption of Ca2+ in the small intestine
How many litres of plasma are filtered by the kidneys per day?
180L
Of our 5L of blood, about 3L are plasma. How many times do we filter this 3L of plasma per day?
60
What percentage of the filtrate is reabsorbed?
99%
99% of the filtrate is reabsorbed. What happens to the other 1%?
it is excreted as urine
How may years does the kidney so without breaking down?
70 years
What are the 3 sections of the kidney called?
- capsule
- cortex
- medulla
Describe the capsule of the kidney
this is the outermost layer of the kidney and it covers the kidney
Describe the cortex of the kidney
this is the outer portion of the kidney (inner from the capsule) and it has invaginations into the medulla
Describe the medulla of the kidney
this is the inner most portion of the kidney and it is where the medullary pyramids are located
As well as the capsule, cortex and medulla, what else is there in the kidney?
What is this for?
the pelvis
this is for collecting the urine to take it to the ureter
What arteries supply the kidney?
the renal arteries
What veins take blood away from the kidney?
renal veins