Physiology, Oxygen Transport

Question 1

____ is essential for ATP generation through oxidative phosphorylation, and therefore must be reliably delivered to all metabolically active cells in the body

Answer 1

Oxygen

Question 2

In the setting of hypoxia or low blood oxygen levels, ____ can rapidly occur

Answer 2

irreversible tissue damage

Question 3

Hypoxia can result from (3)

Answer 3

1. impaired oxygen-carrying capacity of the blood
2. impaired unloading of oxygen from hemoglobin in target tissues
3. restriction of blood supply

Question 4

Blood becomes typically saturated with ___ after passing through the lungs

Answer 4

oxygen

Question 5

____ returns to the heart and is distributed throughout the body by way of the systemic vasculature

Answer 5

Oxygenated blood

Question 5

____ returns to the heart and is distributed throughout the body by way of the systemic vasculature

Answer 5

Oxygenated blood

Question 6

Oxygen is carried in the blood in two forms

Answer 6

bound to hemoglobin within red blood cells

dissolved in the plasma

Question 7

The most critical measures of adequate oxygen transportation are ___ & ___

Answer 7

hemoglobin concentration and oxygen saturation

Question 8

play essential roles in oxygen transport

Answer 8

lungs
heart
vasculature
red blood cells

Question 9

are the respiratory organs responsible for the exchange of gasses between the bloodstream and the atmosphere

Answer 9

lungs

Question 10

Venous blood entering the lungs typically has a partial pressure (PO) of ___

Answer 10

40 mm Hg

Question 11

Upon passing through the alveolar and pulmonary capillaries, ___ and ___ are allowed to equilibrate across the blood-air barrier, resulting in carbon dioxide removal from the blood and oxygen absorption

Answer 11

oxygen
carbon dioxide

Question 12

arterial blood leaving the lungs has a PO of approximately ___

Answer 12

100 mg Hg

Question 13

Oxygenated blood is carried through the cardiovascular system to ___

Answer 13

peripheral tissue

Question 14

The compensatory mechanism most relevant to the discussion of oxygen transport is the production of the hormone ____

Answer 14

erythropoietin (EPO)

Question 15

where erythropoietin is produced

Answer 15

peritubular fibroblasts in the renal cortex

Question 15

stimulates the proliferation and differentiation of red blood cells (erythrocytes) in the red bone marrow

Answer 15

Erythropoietin

Question 16

The process of ____ will increase the number of
erythrocytes and subsequent increase in total hemoglobin

Answer 16

erythropoiesis

Question 17

the primary carrier of oxygen in humans

Answer 17

Hemoglobin

Question 18

Approximately ___% of total oxygen transported
in the blood is bound to hemoglobin, while only __% is dissolved directly in plasma

Answer 18

98
2

Question 19

Hemoglobin is a metalloprotein with four subunits composed of an ___ group attached to a ___

Answer 19

iron-containing heme
globin polypeptide chain.

Question 20

Factors that contribute to a right shift in the oxygen
dissociation curve

Answer 20

increased body
temperature
decreased pH
increased 2,3-BPG

Question 21

Regulation of the unloading of oxygen from the red blood cells to the target tissues is mainly by the concentration of ___ within erythrocytes

Answer 21

2,3-bisphosphoglycerate (2,3-BPG)

Question 22

preferentially binds to and stabilizes the deoxygenated form of hemoglobin, resulting in a lower affinity of hemoglobin for oxygen

Answer 22

2,3-BPG

Question 23

Oxygen is measured in the blood in three ways:

Answer 23

partial pressure of dissolved oxygen
oxygen concentration
hemoglobin saturation

Question 24

Oxygen first has to dissolve in ___ before it can bind to hemoglobin

Answer 24

blood

Question 25

The amount of dissolved O2 depends on the oxygen gradient between the ___ and ___ and the ease at which oxygen can move through the alveolar lung tissue itself

Answer 25

alveoli
blood

Question 26

The most critical clinical test in assessing the efficacy of oxygen transportation is the ___

Answer 26

concentration of oxygen (CaO)

Question 27

A persistent reduction in oxygen transportation capacity is most often the result of

Answer 27

anemia

Question 28

a decrease in the total amount of hemoglobin in the blood

Answer 28

anemia

Question 29

are an essential class of inherited disorders resulting in the defective production of hemoglobin

Answer 29

Thalassemias

Question 30

An individual with thalassemia has a mutation that impairs the production of the ___ of hemoglobin

Answer 30

globin polypeptide chain

Question 31

When deoxyhemoglobin polymerizes, it forms fibers that alter the shape of erythrocytes in a process known as ___

Answer 31

sickling

Question 32

carbon monoxide poisoning

Answer 32

carboxyhemoglobinemia

Question 33

The oxygenation process can be categorized into three stages:

Answer 33

oxygenation
oxygen delivery
oxygen consumption.

Question 34

will result in a decreased oxygenation of
blood

Answer 34

Respiratory failure

Question 35

the rate of oxygen transport from the lungs to the microcirculation

Answer 35

Oxygen delivery

Question 36

Oxygen delivery is dependent on

Answer 36

cardiac output and arterial oxygen content