Respiratory Physiology Part 2

Front 1

Plateau rang of O2 Hb dissociation curve

Back 1

60-100mmHg

Therefore I alveolar PO2 a little below normal there is little change in Hb saturation

Front 2

Steep portion of O2- Hb dissociation curve

Back 2

Rand of Po2 in tissues, O2 unloaded

Front 3

Shift to the right in O2-HB dissociation curve

Back 3

Less Hb saturation

Aka O2 unloads more easily/loads less easily

Reasons:

1. increase Pco2

2. Decrease pH

3. Increase temp

Increase metabolism (e.g. exercise)

Front 4

Shift to left of dissociation curve

Back 4

Hb more saturation aka. Loads easier

Cause by (the conditions at the lungs)

1. Decrease Pco2 and temp

2. Increase pH

Front 5

CO2 carried in 3 ways

Back 5

1. Dissolved in plasma 8%

2. Bound to hemoglobin 20%

3. As bicarbonate (HCO3-) 72%

Front 6

CO2 levels In the plasma

Back 6

45mmHg = deoxy

40mmHg = oxygenated

Front 7

Carbamino Hb

Back 7

CO2 on hemoglobin globin

Front 8

Carbonic anhydrase in RBS

Back 8

Front 9

HbH

Back 9

Hemoglobin and H+

Acts as a acid/base buffer

Front 10

Chloride shift

Back 10

HCO3- being transported out of RBC to plasma in exchange for Cl-

(Allows more HCO3- to be made)

Front 11

Deoxy Hb

Back 11

HbH or HbCO2

Front 12

Haldane effect

Back 12

HbO2 binds CO2 and H+ poorly, therefore CO2 is released

Front 13

2 groups of neurons at respiratory centers in Medulla

Back 13

1. Ventral respiratory groups

2. Dorsal respiratory groups

Front 14

VRG

Back 14

Generate rate

Expiratory and inspiratory neurons

Front 15

DRG

Back 15

Receive chemorecpetor input and modify VRG output

Front 16

Inspiratory neurons

Back 16

Impulses down spinal cord to

1. Phrenic nerve (innervetes diaphragm)

2. Thoracic nerve(innervate ext. Intercostal)

Front 17

Expiratory neurons

Back 17

Fire to inhibit inspiration neurons

(Expiration occurs passively)

Front 18

Pontine respiratory centres

Back 18

Work with medullary centers to make breathing smooth and even

If damaged: gasping and irregular

Front 19

Lung stretch receptors

Back 19

In smooth muscle of bronchi and bronchioles

Hering breuer reflex

Front 20

Hering breuer reflex

Back 20

Receptors overstretched on insp.

Leads to

Inhibit Insp. Neurons

Relaxes mucles (expiration)

Front 21

Volentary control

Back 21

Primary motor cortex to skeletal muscle (bypass medulla)

Medulla can override voluntary control

Front 22

Chemical control

Back 22

Via. Chemoreceptors

Peripheral (carotid and aortic bodies)

Central (medualla oblongata)

Front 23

Peripheral chemoreceptors

Back 23

Weakly sensitive to Pco2

Very sensitive to H+

Front 24

Po2 of 50-60mmHg

Back 24

End of plateau of HB-O2 curve

Stimulates peripheral chemoreceptors

Emergency situations

- often caused by lung disease or low atm Po2

Front 25

Central chemoreceptors

Back 25

Respond indirectly to arterial Pco2

ONLY responds to H+

CSF poorly buffered so small change stim. Repsonse

Front 26

Resting arterial Pco2

Back 26

40mmHg (37-43mmHg)

Front 27

Hyperventilation

Back 27

Decrease arterial Pco2 causes cerebral vasoconstriction

Decrease Po2 to brain = dizziness

Front 28

Hypoventilation

Back 28

Increase arterial Pco2 increase H+

Causes CNS confusion

Front 29

Acidosis

Back 29

Increase H+

Front 30

CO poisoning

Back 30

CO binds 210x stronger to Fe than O2

Resulting in decline of total O2

Front 31

CO

Back 31

Incomplete burning of gas, coal, wood, cigarettes