gas transport by blood

Question 1

The most abundant gas in the atmosphere

Answer 1

nitrogen

Question 2

Air sum of all the partial pressures is approx.

Answer 2

760 mmHg

Question 3

air composition at sea level-partial pressure of oxygen

Answer 3

160 mmHg

Question 4

percent of oxygen of air

Answer 4

21%

Question 5

how to calculate partial pressure of O2

Answer 5

Pp Oxygen = % composition of air x P total

Question 6

What happens at altitude?

Answer 6

air becomes less dense, O2 composition remains the same partial pressure of O2 changes , exerting less pressure

Question 7

diffusion occurs due

Answer 7

partial pressure gradient

Question 8

partial pressure of O2 is higher in pulmonary capillaries or in alveoli?

Answer 8

aveoli

Question 9

t/f pressure force for diffusion of CO2 is lower than O2

Answer 9

true

Question 10

henry’s law

Answer 10

Amount of gas dissolved in a liquid is directly proportional to its partial pressure at a constant temperature

Question 11

Partial pressure of O2 in arterial blood

Answer 11

100mmHg

Question 12

t/f at higher pressure more gas will dissolve

Answer 12

true

Question 13

t/f at lower gas pressure less gas will dissolve

Answer 13

true

Question 14

oxygen transport in blood

Answer 14

dissolved in blood
bound to hemoglobin

Question 15

percent of O2 dissolved in blood

Answer 15

3% dissolved in plasma

Question 16

percent of o2 bound to hemoglobin

Answer 16

97%

Question 17

t/f the o2 dissolved in blood plasma are the ones that exert partial pressure of O2

Answer 17

true

Question 18

once bound to hemoglobin O2

Answer 18

does not exert pressure

Question 19

O2 pressure in blood cannot be used to

Answer 19

determine quantity of O2 in blood

Question 20

what do you need to now to calculate quantity of O2 in blood?

Answer 20

Hb concentration
Oxygen saturation in arterial blood

Question 21

t/f oxygen saturation depends on partial pressure of oxygen

Answer 21

true

Question 22

Hb structure

Answer 22

Quaternary protein: 2 ⍺ chains and 2 β chains
Each chain is bound to a red pigment: Heme
Ferrous iron (Fe2+) which combines with O2
Each molecule of Hb combine with 4 molecules of O2

Question 23

OxyHg-Dissociation curve

Answer 23

Describes the relationship between SaO2 and oxygen tension

Question 24

t/f Oxygen affinity for the heme group depends on the oxygenation of the others

Answer 24

true

Question 25

p50 is the PaO2 pressure at which

Answer 25

50% of the Hb is saturated

Question 26

t/f Each specie has a specific p50

Answer 26

true

Question 27

Oxygen transport: OxyHg-Dissociation curve = curve to the right

Answer 27

affinity O2-Hb decreased

Question 28

Oxygen transport: OxyHg-Dissociation curve = curve to the left

Answer 28

Increased O2 – Hb binding affinity

Question 29

Causes of Oxygen transport: OxyHg-Dissociation curve = curve to the left

Answer 29

Metabolic alkalosis with low PaCO2 and pH increased Low temperatures: Hypothermia diphosphoglycerate decreased: old RBC transfusions O2 binding affinity increased: it is more difficult for the Hb to offloading O2

Question 30

Causes of Oxygen transport: OxyHg-Dissociation curve = curve to the right

Answer 30

Metabolic acidosis, ph. is low, and CO2 is high – Metabolic active tissues Increased of Temperature Increased in the concentration of 2.3DPG O2 binding affinity for the Hb decreases: Hb releases easily the O2

Question 31

forms of hemoglobin transport : physiological

Answer 31

Deoxy-hemaemoglobin Oxy-hemoglobin HbF: fetal Hg (2 ⍺ and 2 γ)

Question 32

forms of hemoglobin transport : pathological

Answer 32

HbS: people with sickle cell diseases (abnormal β chain) MetHb- Methemoglobin COHb – Carbon monoxide hemoglobin

Question 33

Methemoglobin

Answer 33

Fe2+ gets oxidized to Fe3+ form of the Hb does not bind to O2 – Oxygen capacity is decreased

Question 34

treatment for Methemoglobin

Answer 34

methylene blue

Question 35

t/f CO and O2 bind the same sites on the Hb- they compete each other

Answer 35

true

Question 36

t/f Direct relation between amount of oxygen and Hb

Answer 36

true

Question 37

Hufner’s Constant

Answer 37

1g of Hb can combine to 1.34ml O2

Question 38

3 forms of blood transport of CO2

Answer 38

Dissolved - 5% in arterial blood Reacting with H2O and producing Bicarbonate – Effect of Carbonic Anhydrase In reaction with Hb and plasma proteins as carbaminohemoglobin

Question 39

The majority of CO2 in arterial blood is transported reacting

Answer 39

Co2 + H2O, inside the RBC as carbonic acid

Question 40

t/f Pathological forms of the Hb can altere the bounding reaction with O2

Answer 40

true