Cremo review

Question 1

The range of [H+] that corresponds to a normal blood pH is

Answer 1

35-45 nM

Question 2

In an unopened bottle of soda water, the partial pressure of the gas above the liquid is

Answer 2

The same as in the liquid

Question 3

An acidemic patient with normal lung and kidney function would most likely have recently experienced which of the following?

Answer 3

[HCO3-] will increase

Question 4

When a sample of whole blood is exposed to an increased PCO2, what happens?

Answer 4

[HCO3-] and [H+] will increase

Question 5

What is the relative concentration of O2 (in mm Hg) in dry air in Reno?

Answer 5

0.21·680 = 143mmHg

Question 6

Which of the following has the highest PCO2 in the normal human?

Answer 6

Venous blood

Question 7

When a sample of whole blood is exposed to an decreased PCO2, what will occur?

Answer 7

pH will increase

Question 8

Which set of values best represent PCO2 levels related to human physiology?
Inspired air: expired air: alveolar air: venous blood: arterial blood

Answer 8

clinically zero: 4%; 1.2 mM; 1.35 mM; 1.2 mM

Question 9

You can calculate the pH in plasma by plugging in measured values of PaCO2 and [HCO3-] using the Henderson equation. Do you have to account for other buffers present in the plasma to get the correct result for pH?

Answer 9

No, if the values I have measured are correct, the pH will be exactly what the equation says it will be

Question 10

Bicarbonate is added to the blood by acid-producing cells in the stomach in response to a meal. Which best describes the buffering reaction that would mitigate pH changes due to the added bicarbonate?

Answer 10

HbH+ + HCO3 - →Hb + H2CO3 →Hb + CO2 + H2O

Question 11

Which is the buffer system with the highest capacity to mitigate pH changes in the blood due to endogenous acid production?

Answer 11

Bicarbonate system because it is in the highest concentration and is an open system

Question 12

Which of the following has the lowest PCO2 in the normal human?

Answer 12

Inspired air

Question 13

You have a patient who is hypoxemic, but has a normal P(A-a)O2. What could be said about this patient?

Answer 13

They are either hypoventilating or they are experiencing a low PIO2

Question 14

In pure emphysema, the lung is defined by areas of greatly enlarged air spaces with disruption of alveolar walls. What happens to the V/Q ratio?

Answer 14

High V/Q ratio

Question 15

In pure bronchitis, there is abundant mucous secretions in the bronchial tree and narrowing of small airways due to inflammation and wall edema. What happens to the V/Q ratio?

Answer 15

Low V/Q ratio

Question 16

In a lung with an embolism blocking the main artery, what will increase: physiologic dead space, regions with low V/Q, regions with high V/Q?

Answer 16

All of the above

Question 17

An individual alveolus in a state of atelectasis…

Answer 17

has essentially ZERO ventilation

Question 18

A patient with a normal pCO2 but a high p(A-a)O2 difference may have

Answer 18

asthma

Question 19

Four basic mechanisms of hypoxemia

Answer 19

1. a decrease in PIO2
2. pure hypoventilation
3. anatomic shunt
4. V/Q mismatch

Question 20

What is the hallmark of hypoventilation as a cause of hypoxia?

Answer 20

Elevated PaCO2

Question 21

In a normal lung, is the V/Q ratio usually greater than or less than one?

Answer 21

A bit less than one

Question 22

Alveolar gas exchange equation

Answer 22

PAO2 = %O2(Pb-47) - 1.2*PaCO2

Question 23

Which protein has the most iron bound to it on a mol iron/mol protein basis?

Answer 23

Ferritin in the tissues

Question 24

Which proteins are involved in the uptake of iron from the gut lumen into the plasma?

Answer 24

Ferroprotin
DMT1
Hephaestin
Ferric reductase

Question 25

You have a patient with hemochromatosis. What symptoms might you observe?

Answer 25

Elevation in serum ferritin levels.

Hemosiderin in the parenchymal cells of the liver.

Question 26

The aggregated form of ferritin often seen in patients with iron overload is called:

Answer 26

hemosiderin

Question 27

erythropoiesis is stimulated by:

Answer 27

hypoxia

Question 28

What is the rate limiting step during the biosynthesis of heme?

Answer 28

ALA synthase

Question 29

The color of a healing bruise goes from reddish-purple to green to yellow. This color sequence is due to the conversion of:

Answer 29

localized heme to biliverdin to bilirubin

Question 30

What kinds of things can cause conjugated hyperbilirubinemia?

Answer 30

Biliary tree inflammation
Common bile duct obstruction
Hepatitis

Question 31

What catalyzes the rate liming step in heme catabolism?

Answer 31

Heme oxygenase

Question 32

Regulation of heme synthesis depends upon the isoform of this enzyme:

Answer 32

delta-ALA synthase

Question 33

T/F: Men can donate more blood than women without risking iron deficiency?

Answer 33

True

Question 34

Two major sites of heme synthesis:

Answer 34

hepatocytes

developing RBCs

Question 35

Where is erythropoietin produced?

Answer 35

Kidneys

Question 36

What is the most likely cause of jaundice in a newborn infant?

Answer 36

Low glucuronidyl transferase activity

Question 37

The major site of storage of iron in the body

Answer 37

liver parenchymal cell

Question 38

Are the processes where iron is normally lost from the body on a daily basis regulated?

Answer 38

No

Question 39

What does hepcidin do?

Answer 39

Inhibits the processes that put iron into the blood

Question 40

How might an iron deficiency appear clinically?

Answer 40

Low serum ferritin

Question 41

A jaundiced patient has normal indirect bilirubin but elevated direct bilirubin. Why might this be?

Answer 41

Obstructed gall bladder

Question 42

Important enzyme that is involved in the mechanism to sense the concentration of O2 in a cell

Answer 42

Prolyl hydroxylase