(final) Lecture 12 (5/18/16) PT. 1

Question 1

What is hyperconcentration? What allows hyperconcentration of substances?

Answer 1

“concentrating the filtrate that we’re creating when we’re filtering our blood” - Noriega
Countercurrent exchange allows this

Question 2

Definition of countercurrent exchange:

Answer 2

a pair of adjacent channels or tubes containing fluids flowing in opposite directions and having a gradient directed between one channel and the other
*stuff can flow between tubes

Question 3

When the rate of transport from the top tube to the bottom tube is the same as the rate of transport from the bottom tube to the top tube, what is that called?

Answer 3

equilibrium

*no net transfer

Question 4

If the concentration gradient remains the same the entire time those tubes are passing by each other, will it reach equilibrium?

Answer 4

No

*the top tube will continue to be able to transfer into the bottom tube

Question 5

In a warm environment/on a hot day, you want to get rid of excess heat. Are we dealing with countercurrent exchange?

Answer 5

No; we’re trying to get rid of heat, not conserve it.

Question 6

In a cold environment/on a cold day, you want to retain heat. Are we dealing with countercurrent exchange?

Answer 6

Yes; we’re trying to conserve as much heat as possible

Question 7

What is the smallest functional unit of the kidney?

Answer 7

nephron

*filtration of blood

Question 8

The kidney/renal lobe consists of…

Answer 8

renal pyramid (medulla)
renal cortex
*and a bunch of nephrons

Question 9

True or false:

One collecting duct can collect from multiple nephrons.

Answer 9

true

Question 10

The countercurrent exchange in a nephron is at the…

Answer 10

Loop of Henle

Question 11

There is active transport in only one direction in the kidney. What’s being transported and to where?

Answer 11

Salts are being transported to concentrate salts in the urine

Question 12

What makes up the renal corpuscle?

Answer 12

Bowman’s (nephron) capsule

Glomerulus

Question 13

What does the glomerulus do?

Answer 13

It is a ball of capillaries that exchanges substances

Question 14

What is the “beginning” of the nephron and also the tube/duct system of the nephron?

Answer 14

Bowman’s capsule

Question 15

Where does the filtrate that comes from the renal corpuscle go?

Answer 15

The lumen of Bowman’s capsule

Question 16

From Bowman’s capsule, where does the filtrate go?

Answer 16

Proximal convoluted tubule

Question 17

After the proximal convoluted tubule, where does the filtrate go?

Answer 17

Loop of Henle

Question 18

Is the Loop of Henle in the cortex or the medulla?

Answer 18

medulla

the filtrate goes from the cortex to the medulla to the cortex

Question 19

After the Loop of Henle, where does the filtrate go?

Answer 19

Distal convoluted tubule

Question 20

What’s the initial part of the Loop of Henle? What’s the later part?

Answer 20

Descending limb

Ascending limb

Question 21

Through what does the filtrate go when it enters the renal corpuscle?

Answer 21

the afferent arteriole

Question 22

What is the afferent arteriole doing?

Answer 22

bringing blood into the glomerulus

Question 23

The blood goes through the capillaries in the glomerulus and comes out where?

Answer 23

the efferent arteriole

Question 24

The afferent and efferent arterioles make a V with a little “crotch” in the middle. What is in between them?

Answer 24

the distal convoluted tubule

Question 25

Why is it significant that the distal convoluted tubule is in between the afferent and efferent tubules?

Answer 25

There is a collection of cells in that area where the vessel and the tube are next to each other

Question 26

What are the cells called that are in between the distal convoluted tubule and the glomerulus?

Answer 26

juxtaglomerular cells

Question 27

What do the juxtaglomerular cells make up?

Answer 27

the juxtaglomerular apparatus

Question 28

What do the juxtaglomerular cells sense?

Answer 28

pressure

Question 29

What is the significance of the juxtaglomerular cells sensing pressure?

Answer 29

blood is made up of mostly plasma and plasma is mostly water; the cells are sensing the water pressure to see how much water there is in the body
*the higher the blood pressure, the higher the water pressure

Question 30

What solvent is used in the kidney?

Answer 30

water

Question 31

Kidney function:

Answer 31

flitration

water balance regulation

Question 32

The filtration process begins with the…

Answer 32

filtration membrane at the renal corpuscle

Question 33

Capillaries have holes called…

Answer 33

fenestration

Question 34

What initiates concentration of glomerular filtrate?

Answer 34

proximal convoluted tubule

Question 35

75% of _______ is removed by active transport in the proximal convoluted tubule. What follows passively?

Answer 35

sodium

chloride

Question 36

The remaining fluid concentration in the nephron tube is ___________ as that of surrounding interstitial fluid.

Answer 36

about the same

Question 37

Remember…

What do you need for depolarization?

Answer 37

sodium

Question 38

Most of the sodium you’re recovering during reabsorption is going into the…

Answer 38

proximal convoluted tubule

Question 39

“Drawing the sodium (positive) back in, the chloride (negative) does what?”

Answer 39

passively comes back in

Question 40

What kind of cells are in the medulla?

Answer 40

mesenchymal