B4W1 Renal

Question 1

What is the concentration of components in plasma from highest to lowest?

Answer 1

Na, Cl, HCO3, K, Ca, PO4

Question 2

What is the major osmolyte of the extracellular fluid?

Answer 2

Na+

Question 3

Compare the ionic composition between interstitial fluid and plasma.

Answer 3

Essentially the same but there is no fluid protein in the interstitial fluid

Question 4

Compare Na+, Cl-. and K+ concntrations between extra and intracellular fluid.

Answer 4

Extracellular
- High Na+ and Cl-
- Low K+

Intracellular
- Low Na+ and Cl-
- High K+

Question 5

Effect of increasing extracellular NaCl?

Answer 5

Swelling of the ECF compartment
Depletion of ICF compartment

Question 6

Effect of adding pure water?

Answer 6

Increase ICF compartment
Depletion of the ECF compartment

Question 7

Effect of isotonic NaCl Water?

Answer 7

Increase ECF compartment
No change in ICF compartment

Question 8

What is the major determinant of ECF volume?

Answer 8

Total body Na+

Question 9

What is the primary function of the kidneys?

Answer 9

Filtration
Reabsorption
Secretion

Question 10

What percentage of cardiac output is received from the kidney?

Answer 10

20%

Question 11

How can you identify superficial glomeruli?

Answer 11

They are the only glomeruli that have a bifurcated interlobular arteries.

Question 12

What is a claudin?

Answer 12

A claudin is a family of proteins that determine the selectivity of tight junctions

Two claudins on two cells near one another form a selectivity barrier

Question 13

Leaky Junction Characteristics

Answer 13

Electrical Resistance, Chemical Gradient, Transepithelial Voltage are low

Transport Rate is high

Question 14

What is Glomerular filtration rate?

Answer 14

Rate of fluid movement from capillary space into Bowman’s Space
Volume filtered per unit of time

Question 15

Average Kidney Glomerular Filtration Rate

Answer 15

180 L/Day

Question 16

Average Daily Urine Amount

Answer 16

1-2 L/Day

Question 17

Endogenous Molecule Used to Measure GFR

Answer 17

Creatinine

Question 18

What is the functional unit of the kidney?

Answer 18

The nephron

Question 19

Two main Components of a Nephron

Answer 19

Glomerulus and Tubule

Question 20

Glomerulus Function

Answer 20

Filter Blood

Question 21

Nephron Tubule Function

Answer 21

Convert Filtrate into Urine

Question 22

What are the two main types of nephrons?

Answer 22

Cortical and Juxtamedullary
85% Cortical
15% Juxtamedullary

Question 23

Main components of Glomerulus or Renal Corpuscle

Answer 23

Vasculature, Mesangial Cells, and Bowman’s Space. All of which are incased by epithelial cells to form Bowman’s Capsule

Question 24

Endothelial Cell Characteristics of the Proximal Tubule

Answer 24

Extensive Apical membrane with a lot of in-folding, has many mitochondria, and a large nucleus

Question 25

What is the Loop of Henle

Answer 25

Medullary Structure that contains S3 Segment of the Proximal Tubule, thin descending limbs, thin ascending limbs, and thick ascending limbs.

Question 26

Segments of the Proximal Tubule

Answer 26

S1 S2 and S3 S1 Renal Cortex - Greatest Rate of Transport S2 Medullary S3 Outer Medullary - Has lowest rate of transport - Has the highest gradient

Question 27

Thin Descending Limbs

Answer 27

5% of filtered water reabsorbed but no Na+ Thin cells, few mitochondria, no membrane in-folding

Question 28

Thin Ascending Limbs

Answer 28

Na+ Maybe reabsorbed or secreted depending on the gradient Thin Cells, few mitochondria, and no membrane in-folding

Question 29

Thick Ascending Limbs

Answer 29

Reabsorb -20-30% NaCl -K+ -Ca2+ and Mg2+ -HCO3- Increase NaCl reabsorption in response to vasopressin Secrete Tamm-Horsfall Protein Does not reabsorb water A lot of mitochondria, little apical membrane in-folding, but a lot of basolateral in-folding

Question 30

Role of Tamm Horsfall Protein (Uromodulin)

Answer 30

Role in immunity and stone prevention

Question 31

Macula Densa

Answer 31

Senses NaCl for tubuloglomerular feedback Regulate Renin Release Release paracrine factor Large nuclei, a lot of mitochondria, basolateral portion is in contact with mesangial cells, the afferent arterioles, and efferent arterioles

Question 32

What characteristics make a goof GFR Marker?

Answer 32

Freely filterable, not reabsorbed or secreted, breakdown or accumulated by kidney, and physiologically inert

Question 33

Downsides of Creatinine as a biomarker

Answer 33

Increases in muscle mass increase creatinine

Question 34

Influences on the glomerular filtration barrier

Answer 34

Blood Pressure/Flow, Urine obstruction, change in extracellular volume, and reaction to hormones