Renal System Flashcards
What are the structures of the urinary system?
- kidney
- ureters
- bladder
- urethra
Contrast contents of male and female urethra
- male: urine + sperm
- female: urine ONLY (shorter and so easier to get UTIs)
Bladder function
store urine
- What are the two urethral/ bladder sphincters?
- What type of muscle are they?
- How are they controlled?
- internal urethral sphincter- smooth m. under involuntary unconscious control (normally sympathetic NS keeps sphincter constricted to NOT let out urine)(when parasympathetics activate detrusor to contract to start urinating, it also causes sympathetic inhibition, which relaxes IUS)
- external urethral sphincter- skeletal m. under voluntary conscious control. (somatic NS)
both have to be RELAXED for micturition aka voiding aka urination
What part of kidney (medulla or cortex) does most filtration of blood occur?
renal cortex
bc nephron filtering units mainly are here
What part of the kidney (cortex or medulla) is the site of EPO production?
renal cortex
Renal medulla general function
has tubules of the nephron that reabsorb (as well as secrete) substances and concentrates urine
The renal artery brings [____] blood to the kidneys from the [_____]
- oxygenated
- abdominal aorta
The renal [_____] brings [____] blood to the heart
- vein
- filtered deoxygenated
What is the site of filtration?
renal corpuscle = glomerulus + bownman (aka glomerular) capsule
What is the structural and functional unit of the kidney?
the nephrons (bowman’s capsule + tubules)
What is the general blood flow once we get to AA of the kidney’s?
AA brings blood to be filtered to the glomerulus –> filtration occurs in the glomerulus into bowman’s capsule –> 2 paths (1. filtrate moves through PCT, thin descending loop of henle, thick ascending loop of henle, early DCT, late DCT, and the collecting duct –> renal pelvis –> ureter –> bladder –> urethra) (2. some substances go directly through glomerulus and into the EA –> peritubular capillaries (invovled in reabsoprtion and secretion) –> interlobular vein –> arcuate vein –> interlobar vein –> renal vein –> inferior vena cava)
Constriction and dilation of the [___] and [___] control the GFR
- AA
- EA
The consistent [__] pressure in the glomerular capillaries allows for filtration to occur in the glomerulus
high
note: this pressure is maintained by general body arterial pressure as well as AA being always more so dilated (so increase pressure downstream) and EA being more so constricted (so increase pressure upstream)
- What is the capillary within the nephron?
- What part of the kidney (cortex or medulla) is it located?
- What does this capillary do?
- glomerulus
- renal cortex
- filters blood out of the AA INTO bowman’s capsule through blood pressure.
The nephron tubules are surrounded by [___] where substances are [____] back into the capillaries OR [___] into the nephron tubules
- peritubular capillaries
- reabsorbed
- secreted
What are considered the nephron filtrating units?
Where are these located?
glomerulus
located in renal cortex
What are the parts of the nephron invovled in the reabsorption and secretion of substances?
Where are these mainly located?
tubules
in renal medulla (mainly)
How is the kidney able to filter blood?
good blood pressure is maintained throughout body and so at glomerular capillaries to push fluid from the capillaries into bowman’s space