Unit 3 Renal Physiology (BIOL 460)

Lower right label

renal cortex

Upper right label (entire thing)

renal medulla

Cone shaped tissue masses located within the medulla

renal pyramid

Lower left label

ureter

Middle left label

renal pelvis

Ureters, bladder, and the urethra ___ (do/do not) alter the composition of urine

do not

The functional unit of the kidney

nephron

There are about ___ nephrons in each kidney

1 million

The ball of capillaries that filters the fluid from the capillaries; no oxygen or nutrient exchange occurs here

glomerulus

Afferent arterioles deliver blood ___ (to/from) the glomerulus

to

Efferent arterioles deliver blood ___ (to/from) the glomerulus

from

The ___ (afferent/efferent) arteriole has a larger diameter

afferent

___ ___ surround and intertwine around the rest of the nephrons

peritubular capillaries

The peritubular capillaries supply the renal tissue with

blood

Nephrons can be ___ or ___

cortical or juxtamedullary

The peritubular cappilaries surrounding juxtamedullary nephrons are called

vasa recta

Vasa recta are ___ (circuitous and intertwined/straight and form hairpin loops)

straight and form hairpin loops

Nephrons in the corticals are ___ (circuitous and intertwined/straight and from hairpin loops)

circuitous and intertwined

The ___ ___ is a double walled sac that surrounds the glomerulus, together forming the renal corpuscle

Bowman’s capsule

The fluid that collects in the Bowman’s capsule is almost identical in composition to plasma, except that it has almost no ___

protein

The ___ convoluted tubule is located closer to the glomerulus

proximal

The ___ convoluted tubule is located farther from the glomerulus

distal

This structure is not technically a part of the nephron because they are shared among numerous nephrons

collecting duct

The ___ limb of the loop of Henle is from the PCT and travels down into the medulla

descending

The ___ limb of the loop of Henle goes to the DCT and travels up into the cortex

ascending

The PCT and DCT are located in the renal ___

cortex

The loop of Henle and collecting duct are located in the renal ___

medulla

The loops of Henle of cortical nephrons dip ___ (slightly/fully) into the medulla

slightly

The loops of Henle of juxtamedullary nephrons dip ___ (slightly/fully) into the medulla

fully

The percentage of nephrons that are juxtamedullary correlates with greater ___ ___ ability

urine concentrating

List the three key processes of urine production

glomerular filtration, tubular reabsorption, tubular secretion

About ___% of plasma that goes into the glomerulus is pushed into the Bowman’s capsule

20

The glomeruli in your kidneys filters ___ L per day

180

What percentage of the filtrate volume from the glomeruli gets reabsorbed back into the body

99%

The 80% of plasma that was not filtered leaves the glomerulus and travels to the ___ ___ for tubular secretion

peritubular capillaries

Glomerular filtration is ___ (selective/nonselective)

nonselective

Tubular reabsorption is ___ (selective/nonselective)

selective

Tubular secretion is ___ (selective/nonselective)

selective

Glomerular filtration is what is filtered ___ (from/back into) the blood

from

Tubular reabsorption is selective reclaiming ___ (from/back into) the blood

back into

Tubular secretion is selective elimination ___ (from/back into) the blood

from

The glomerulus is made of vessels that are surrounded by

podocytes

Podocytes form filtration ___

slits

Glomerular filtration is ___-based

size

The podocytes make ___ (large/small) filtration slits

small

The pores made by podocytes are too small for ___ to go through

proteins, rbc

Podocytes do allow the following to go through to the lumen of the Bowman’s capsule

water, glucose, amino acids

Glomerular filtration is passive, driven by ___ gradient

pressure

Glucose ___ (is/is not) regulated in the urine

is not

One goal of tubular reabsorption is retrieve all glucose and important nutrients ___ (based on/regardless of) need

regardless of

One goal of tubular reabsorption is to retrieve water, salts, and ions ___ (based on/regardless of) need

based on

Sodium itself is pulled out of the PCT into the blood by what primary active pump

Na/K ATPase

The Na/K ATPase pump also provides the energy for secondary active sodium co-transporters. The co-transports now push materials against their gradient ___ (into/out of) the PCT

out of

Secondary active sodium co-transporters also allow what other materials to be reabsorbed into the blood

glucose, amino acids, organic nutrients

Chloride ions follow ___ down the electrical gradient and into the blood

sodium

Water is also reabsorbed by the blood through ___ in the PCT wall and by squeezing between the cells

aquaporins

The movement of water being reabsorbed into the blood also encourages urea to ___ (stay in PCT/diffuse into blood)

diffuse into blood

How fast the people operating a conveyor belt can work is called the

transport maximum

The maximum absorption rate in a particular molecule per time

transport maximum

The number of items on the conveyor belt is called the

renal threshold

The concentration in the blood at which you exceed the transport maximum

renal threshold

Glucose is urinated, not because it’s regulated, but because its ___ ___ has been exceeded

renal threshold

If we reach the renal threshold, we ___ (do/do not) respond by changing the activity of the transporters

do not

List the three variables that play a role in reabsorption, transport maximum, and renal threshold

sodium pumps, amount of molecules, GFR

How fast the belt is moving is called the

glomerular filtration rate

The rate of how much blood passes through the glomerulus per minute

GFR

The descending limb of the loop of Henle is ___ (permeable/impermeable) to water

permeable

The ascending limb of the loop of Henle is ___ (permeable/impermeable) to water

imperable

Aquaporins are found the ___ limb

descending

Co-transporters are found in the ___ limb

ascending

Water leaves the ___ limb

descending

Na, K, and Cl salts leave the ___ limb

ascending

The co-transporters on the ascending limb pump ___ Na, ___ K, and ___ Cl out of the limb

1, 1, 2

The loop of Henle establishes a vertical ___ gradient in the medulla

osmotic

The deeper into the medulla, the ___ (more/less) salty it is

more

The countercurrent multiplier, maintained by the ___, creates the salty gradient in the medulla

loop of Henle

The countercurrent exchange, maintained by the ___, preserves/protects the gradient

vasa recta

Salt diffuses ___ (into/out of) the blood into the ISF from the vasa recta on the way down

into

Salt diffuses ___ (into/out of) the blood into the ISF from the vasa recta on the way up

out of

The countercurrent ___ ensures that the vasa recta doesn’t soak up the entire salt gradient

exchange

A majority of tubular secretion occurs in the ___

PCT

List some substances tubularly secreted in the PCT

H, drugs, toxins, waste

Tubular secretion in the PCT is ___ (active/passive)

active

Tubular secretion ___ (does/does not) occur in the loop of Henle

does not

List the materials tubularly secreted in the DCT

H+, K+

H+ is secreted in the DCT by the electronegative gradient established by the reabsorption of

sodium

Tubular secretion of K+ into the DCT is controlled by what hormone

aldosterone

Obligatory urine volume is ___ mL

500

Filter it and you will ___ it

pee

If you’re critically dehydrated, you will shut down ___ as a means of holding onto your water

filtration

The renal system can be regulated through ___ or ___-controlled mechanisms

GFR or hormone

If GFR is too high, you ___ (lose/retain) salt, water, glucose, etc.

lose

A fast GFR is a ___ (water and salt / glucose and amino acid) issue first and foremost

water and salt

If GFR is too slow, there will be a ___ accumulation

waste

GFR is determined by the net filtration pressure which includes:

glomerular blood pressure, capsule hydrostatic pressure, and osmotic pressure

What is the name of the pressure that forces filtrate out of the glomerulus and into the Bowman’s capsule; it is a reflection of systemic BP and of the fact that the afferent arteriole is larger than the efferent arteriole

glomerular blood pressure

What is the name of the pressure of fluid that is already in the Bowman’s capsule

capsule hydrostatic pressure

What is the name of the pressure that pulls water back into the blood along with the solutes

osmotic pressure

Children with Kwashiokor ___ (can/cannot) conserve their water because they lack protein to create the salty gradient and osmotic pressure to retain water

cannot

Capsule hydrostatic pressure pushes ___ (with/against) the fluid trying to enter to Bowman’s capsule

against