respiration 5

Question 1

lung compliance and elastance

Answer 1

• compliance is how easily the lungs stretch during inhalation
• elastance is ease of returning to shape on exhalation

Question 2

surfactants

Answer 2

• surface tension in alveolar fluid lowers compliance

- reduces surface tension by disrupting cohesive forces between water molecules

Question 3

resistance increases/decreases with…

Answer 3

increases with length and viscosity

descreases with radius

Question 4

airway resistance and diameter

Answer 4

as diameter increases, resistance decreases, and vice versa

• higher resistance requires more work/energy
• diameter is affect by nervous system , hormones, and paracrine messengers

Question 5

bronchoconstriction

Answer 5

caused by parasympathetic nerve stimulation and histamine

Question 6

bronchodilation

Answer 6

caused by sympathetic nerve stim, epinephrine, high CO2, and corticosteroids

Question 7

dead space

Answer 7

air that does not participate in gas exchange

anatomical: volume of trachea and bronchi
alveolar: volume of alveoli that is not perfused

Question 8

tidal volume

Answer 8

volume of air moved in one normal ventilatory cycle

Question 9

alveolar ventilation

Answer 9

volume of air that enters alveoli with each resp cycle

aka VA=VT-VD

Question 10

inspired reserve volume (IRV)

Answer 10

max inspiration beyond normal tidal volume

Question 11

inspiratory capacity (IC)

Answer 11

VT plus IRV

Question 12

expired reserve volume (ERV)

Answer 12

max expiration beyond normal tidal volume

Question 13

vital capacity VC

Answer 13

VT+IRV+ERV

Question 14

residual volume RV

Answer 14

never expired or measured

Question 15

total lung capacity TLC

Answer 15

Vt+IRV+ERV+RV or VC+RV

Question 16

ventilation-perfusion matching

Answer 16

efficient gas exchange at resp surface requires match of vent and blood flow, at a ratio of Va/Q; alveolar ventilation vs rate of flow
-arterioles dilate or constrict to distribute blood to well ventilated alveoli

Question 17

O2 transport, Metalloproteins

Answer 17

• respiratory pigments used to increase oxygen carrying capacity by up to 50x
• proteins contain metal ions which reversibly bind to oxygen
• at tissue surface low PO2 in blood causes release of O2 down its gradient

Question 18

metalloproteins

Answer 18

3 types: hemoglobins, hemocyanins, and hemerythrins

Question 19

hemoglobins

Answer 19

• globin protein bound to heme molecule that contains iron
• usually within blood cells
• appear red when oxygenated
• myoglobin is type of hemoglobin found in muscles
• found in vertebrates, nematodes, crustaceans, and insects

Question 20

hemocyanins

Answer 20

• found in arthropods and molluscs
• contain COPPER, not heme
• dissolved in hemolymph and appears blue when oxygenated

Question 21

hemerythrins

Answer 21

found in brachiopods and some annelids

• contains iron directly bound to protein, no heme involved
• ususaly inside coleomic cells or muscle cells
• appears violet-pink when oxygented

Question 22

oxygen loading

Answer 22

amount of oxygen stored on hemoglobin determind via:

1. amount of pressure oxygen can bring to bear on the system/how much O2 is being loaded=PO22 of the plasma
2. the affinity/ability of the carrier (hemoglobin) to carry O2=Hb=oxygen affinity of hemoglobin

Question 23

oxygen loading and PO2 of envrionment/plasma

Answer 23

high PO2 favours loading, low favours unloading

Question 24

oxygen loading and Hb affinity

Answer 24

high affinity favours loading, low affinity favours unloading

Question 25

hyperbolic oxygen equilibrium graphs

Answer 25

found in myoglobin because each oxygen binds independently

Question 26

sigmoidal oxygen equil graphs

Answer 26

sigmoidal because of cooperativity; hemoglobin has a higher affinity for oxygen since more oxygen bind to its heme

Question 27

factors that affect hb affinity

Answer 27

pH, pCO2, aka the bohr and root effects | -temperature effect and organic modulators

Question 28

bohr effect

Answer 28

higher pH, fewer H+, minimal CO2, and O2 its taken up more easily at resp surface - low pH lots of H+ and CO2 allows O2 more easily released at tissues - bohr effect is a decreased affinity due to increased CO2

Question 29

root effect

Answer 29

increased H+/decreased pH decreases affinity

Question 30

temperature shift

Answer 30

higher temp indicates more active tissues, thus O2 affinity must decrease to move more O2 to tissues

Question 31

organic modulators

Answer 31

act as allosteric regulators, they affect the function of a protein by binding to the non-active sties -can be activators or inhibitors -important in control loops ie 2,3-DPG in mammals and reptiles lowers Hb affinity