Gas transport and blood gases

Question 1

how are gases carried

Answer 1

dissolved in plasma
chemically combined with haemoglobin
covered into a different molecule

Question 2

external respiration

Answer 2

occurs at the level of the lungs
alveoli

Question 3

loading o2

Answer 3

o2 diffuses along its partial pressure gradient from alveolus to blood until equilibrium is reached

Question 4

loading o2

Answer 4

o2 diffuses along its partial pressure gradient from alveolus to blood until equilibrium is reached

Question 5

unloading co2

Answer 5

co2 diffuses along partial pressure gradient from the blood to the alveolus

Question 6

factors influencing external respiration

Answer 6

1. surface area and the structure of the respiratory membrane
2. partial pressure gradients
3. matching alveolar airflow to pulmonary blood capillary flow

Question 7

internal respiration

Answer 7

o2 diffuses from systemic capillaries into cells
co2 cells to capillaries

Question 8

factors influencing internal respiration

Answer 8

1. available surface area
2. partial pressure gradients
3. rate of blood flow (metabolic rate of tissue)

Question 9

internal respiration

Answer 9

at the level of the rest of the body

Question 10

what is involved in internal respiration

Answer 10

myofibers
adipocytes
epithelial cells
immune cells

Question 11

partial pressures of oxygen and carbon dioxide of arterial blood leaving the lung

Answer 11

they’re constant

Question 12

what type of reaction is the binding of action to haemoglobin

Answer 12

reversible

Question 13

label the image

Answer 13

iron atom
haem group
polypeptide chain

Question 14

what occurs when 4 o2s are bound to haemoglobin

Answer 14

haemoglobin is full saturated

Question 15

globin portion

Answer 15

4 polypeptide chains
4 iron pigments called haem groups

Question 16

oxygen bound to haemoglobin

Answer 16

oxyhaemoglobin

Question 17

affinity and saturation

Answer 17

affinity of haemoglobin for oxygen decreases as its saturation decreases

Question 18

what occurs at high oxygen concentrations

Answer 18

oxyhaemoglobin forms

Question 19

what occurs at lower oxygen concentrations

Answer 19

oxyhemoglobin dissociates to haemoglobin and oxygen

Question 20

lungs at sea level

Answer 20

98% saturated

Question 21

lungs at high elevations

Answer 21

95% saturated

Question 22

Haemoglobin saturation at low partial pressure oxygen

Answer 22

Actively contracting muscle uses more oxygen
Lower partial pressure
35% saturated
As partial pressure decreases
Haemoglobin releases much more oxygen to tissues

Question 23

Factors altering Haemoglobin saturation

Answer 23

Increase in affinity:
Shift left

Increased pH
Decreased partial pressure CO2 (Bohr shift)
Decreased BPG

Question 24

O2 to the right

Answer 24

Increased:
H+
Partial pressure CO2
Temperature
2,3-diphosphoglycerate

Question 25

Bohr effect cause

Answer 25

Action on H+ conc Right shift More unloading of O2 at given partial pressure O2 in tissue

Question 26

Effect of decreased temperature

Answer 26

Shift left

Question 27

Carbon Monoxide and O2 transport

Answer 27

Affinity of Haemoglobin for carbon monoxide is 240 times bigger than O2 CO competitively blocks combination of O2 with Haemoglobin CO bound Hb= carboxyhaemoglobin Shifts curve left Leads to severe hypoxia

Question 28

Transport of CO2 in blood

Answer 28

More readily than oxygen 20x more soluble in plasma Arterial blood is 48% Venous blood is 52%

Question 29

CO2 transport

Answer 29

Physically dissolved 5%, arterial blood Physically dissolved as bicarbonate ion, arterial blood Combined Hb 23%

Question 30

Where does carboxyhaemoglobin form

Answer 30

In regions of high partial pressures of CO2

Question 31

Formation of carboaminohaemoglobin

Answer 31

Reversible Lower pCO2 dissociâtes from CH

Question 32

Oxygen saturation of Haemoglobin is affected by

Answer 32

Partial pressure oxygen Ph Temp BPG partial pressure carbon dioxide

Question 33

Haldane effect

Answer 33

Oxygen loading facilitates Carbon dioxide unloading from Haemoglobin