lecture 8 Flashcards
What are the functions of the urinary system?
- regulates
- blood ionic composition
- blood volume/pressure
- blood pH
- conservation of nutrients
- production and secretion of hormones
- assists the liver in detoxification of poisons
- Eliminating ORGANIC WASTES (especially nitrogenous wastes: ammonia, urea, bilirubin, creatine, and uric acid)
What does a renal lobe consist of?
Medulla, cortex, and minor calyx
What is the path of blood flow within the kidney?
What is the path of blood flow to the and from the kidney?
What is the functional unit of the kidney? What are the parts of this unit?
A nephron, it contains two parts: a renal corpuscle and a renal tubule.
What are the three processes for urine to be produced?
- Glomerular filtration
- Tubular reabsorption
- tubular secretion
What are the two layers that surround bowmans capsule?
Bowmans capusle is surrounded by a visceral layer and a parietal layer.
What is important to know about the visceral layer?
- Its is more internal than the parietal
- Consists of modified simple squamous cells called podocytes
- these podocytes have pedicels (modified extensions) that wrap around the capillaries and allow the ultrafiltrate to escape to the bowmans capsule
What is important to know about the parietal layer of the bowmans capsule?
Not much actually, that shit makes up the external wall of the bowmans capsule and is composed of simple squamous epithelium
When looking at an ideal cross section of bowmans capsule what two structures oppose each other by 180 degrees?
The vascular pole (w/macula densa) and the urinary pole
What epithelium are the thick limbs composed of in the nephron? Thin limb compostion?
Thick limbs are composed of: simple cuboidal epithelium
thin limbs are composed of simple squamous epithelium
What are some important distinctions between DCT and PCT in the histological cross section?
- PCT’s are larger in diameter than DCTs
- PCT has a brush border and DCT does not
3.
What is the juxtaglomerular apparatus? What does it do?
The juxtaglomerular apparatus helps to regulate blood pressure in the kidney. It is composed of:
Macula densa + Juxtaglomerular cells + Extraglomerlular Mesangial cells (Lacis cells) = JGA
Whats the pathway of urine in the kidney?
- Blood flow through the kidney (see previous card) When the blood gets to the glomerular caplillaries waste products diffuse through the podocytes and into bowmans capsule
- Bowmans capsule to Proximal convoluted tubule
- Proximal convoluted tubule to thick descending
- Thick descending to thin descending
- Thin descending to thin ascending
- thin ascending to thick ascending
- Thick ascending to Distal convoluted tubule
- Distal convoluted tubule to collecting duct
- Collecting ducts to renal papilla
- Renal papilla to minor calyx
- minor calyx to major calyx
- Major calyx to renal pelvis
- renal pelvis to ureter (note the importance of the distinctino between the renal pelvis and ureter which is the position of the same strucutre in or out of the hilum of the kidney)
What is the composition of epithelium from the bladder to the external urethral orifice in males?
- prostatic urethra - urothelium
- membranous urethra - stratified columnar and pseudostratified columnar epithelium
- spongy urethra - same and membranous but has stratefied squamous at the distal portion
