Exam 3 - Lecture 35 (Org. of Urinary Sys. II) Flashcards
What is the cell type transition from the renal corpuscle to the PCT?
Simple squamous –> cuboidal epithelium
What are 3 atypical features that are present in the cells of the PT?
- Long microvilli
- Lots of mitochondria
- Apical canaliculi
What is the function of long microvilli in the PT?
Increase SA
What is the function of mitochondria in the PT?
Make energy in the form of ATP
What is the function of apical canaliculi in the PT?
Reabsorption at the luminal membrane
Where is the nucleus positioned in the cells of the PT?
Central or close to the basal membrane
Besides long microvilli, mitochondria, and apical canaliculi, what else can we find in the cells of the PT?
lysosomes
Long microvilli of the PT make up the _____.
Brush border
Where is the apical canaliculi positioned in the cells of the PT?
At the cell’s apical surface just deep to the microvilli
Which of the following statements about the cells of the proximal tubule is most accurate?
A) They are simple squamous B) They have an extensive brush border C) They lack mitochondria D) Nuclei are located apically E) They are inefficient at absorption
B) They have an extensive brush border
In what part of the kidney is the PT located?
cortex
Where is the Loop of Henle located in the kidney?
medulla
What is the cell transition from the PT to the LoH?
cuboidal –> squamous epithelium
Why is the epithelium of the LoH so thin?
Because of passive transport occurring there
What are the differences in permeability between the descending and ascending limbs of the LoH?
Descending = permeable to H2O but not to NaCl Ascending = permeable to NaCl but not H2O
What is the characteristic/shape of the nucleus in the LoH?
It bulges
Where in the kidney is the DT located?
Small amount in medulla, mostly in the cortex
What is the cell type of the DT?
Low cuboidal epithelium
What is the positioning of the nuclei in the DT?
Apically located
How many microvilli does the DT have compared to the PT?
Fewer
How many mitochondria does the DT have compared to the PT?
Fewer
What is the H2O permeability status of the DT?
Not permeable to water
When is the only time the later DT is permeable to H2O?
If an anti-diuretic is present
What is the shape of the nucleus in the DT?
Oval-shaped
What is the shape of the nucleus in the PT?
Round
How does the lumen of the DT appear on a histology slide?
clear (not a fuzzy brush border like the PT)
What is the macula densa?
Layer of DT cells that communicate info from the DT to the glomerulus.
What type of cells does the macula densa have?
cuboidal epithelium
Does the macula densa have a basal lamina?
No
What are juxtaglomerular cells?
Specialized smooth muscle cell of the afferent arteriole wall
What 4 things are present in the juxtaglomerular cells?
- Renin (hormone)
- Angiotensin converting enzyme
- Angiotensin I (hormone)
- Angiotensin II (hormone)
Where in the kidney is the collecting tubule found?
Cortex and medulla
What is the size of the CT as it goes further into the medulla?
gets bigger
What two cells are found in the collecting tubules?
- Principal cells
2. Intercalated cells
What two types of CT make up the main CT?
- Medullary CT
2. Papillary CT
What are principal cells important for in the CT?
Reabsorption
Do principal cells have a brush border?
No
What is the purpose of intercalated cells of the CT?
Reabsorption but different than principal cells
What is the cell shape of the CT?
Cells lower than PT but higher than DT
What is a unique characteristic of the nuclei of the CT cells?
Have a pale halo present around them
What is the mucosa of the ureter made up of and where is it located?
Transitional epithelium; overlies lamina propria
What is the lamina propria?
1st layer of the tunica muscularis
What are the 5 layers of the ureter from inner to outermost?
- Mucosa w/transitional epithelium
- Lamina propria
- Tunica muscularis (inner longitudinal)
- Tunica muscularis (outer circular)
- Tunica adventitia
What 4 things are transitional epithelium found in?
- Pelvis
- Ureter
- Bladder
- Urethra
What are the 7 layers of the bladder from innermost to outermost?
- Transitional epithelium
- Lamina propria (outer)
- Lamina propria (inner)
- Tunica muscularis (inner longitudinal)
- Tunica muscularis (middle circular)
- Tunica muscularis (outer longitudinal)
- Tunica adventitia
What is the tunica muscularis of the bladder called?
Dextrusor muscle
What is the tunica adventitia made of?
C.t.
What is the function of the internal sphincter muscle of the bladder?
Involuntary control of micturition
What is the function of the external sphincter muscle of the bladder?
Voluntary control of micturition
What is micturition?
Expelling of urine from bladder
What are the layers of the urethra from inner to outermost?
- Transitional epithelium
- Lamina propria (lg and porous)
- Tunica muscularis (inner circular)
- Tunica muscualris (outer longitudinal)
- Tunica adventitia
What is special about the lamina propria of the urethra?
It is large and porous
What does the urethra do?
Carries urine from bladder to the outside
What does the ureter do?
Carries urine from the kidney to the bladder
What epithelial type lines the LoH?
A) High cuboidal
B) Simple squamous
C) Transitional
D) Low cuboidal
B) Simple squamous
