Gas Exchange

Question 1

Causes dilution of gasses in the upper resp

Answer 1

Humidification

Question 2

Partial pressures of inspired air

Answer 2

Total 760
N2: 601
O2: 159
CO2 0.3
H20: variable

Question 3

Occurs if humidification of air does not occur

Answer 3

Lung tissue damage or infection

Question 4

Pp of H20 in alveoli

Answer 4

47 mm Hg

Question 5

Pp flow of 02

Answer 5

o	159 mm inspired
o	105 alveoli
o	100 arterial
o	40 systemic tissue
o	40 veins

Question 6

Pp flow of CO2

Answer 6

o	0.3 mm Inspired
o	40 alveoli
o	40 artery
o	45 systemic tissue
o	45 veins

Question 7

Increased contact area with RBCs in alveolar capillaries

Answer 7

Thin walls

Question 8

Layers of the resp membrane

Answer 8

• Fluid + surfactant
• Alveolar epithelium
• Basement membrane of epithelium
• Thin interstitial space
• Basement membrane of capillary
  Capillary endothelium

Question 9

Factors influencing diffusion across resp membrane

Answer 9

• Thickness (edema, fibrosis)
• Surface area
• Diffusion constant (co2 more rapid than 02)
• Pressure difference

Question 10

Where oxygen is in transport

Answer 10

• 98.5% hemoglobin

- 1.5% dissolved in blood

Question 11

Where oxygen binds

Answer 11

To the heme (fe) group on hemoglobin, up to 4. Now oxyhemoglobin

Question 12

02 sat in arteries compared to veins

Answer 12

100% art, 80% vein

Question 13

The oxy chart shift to the right means….

Answer 13

More 02 removal

Question 14

the oxy chart shift to the left means

Answer 14

Less 02 removal

Question 15

Causes more 02 removal

Answer 15

• Decrease in pH
• Increase in temp
• Increase in CO2

Question 16

As it gets colder, oxygen is ________ to remove

Answer 16

harder

Question 17

Methods of CO2 transport

Answer 17

• Bicarbonate (70%)
• Hemoglobin (23%)
• Blood (7%)

Question 18

Acidosis effect of nervous system

Answer 18

Depression of CNS

Question 19

Alkalosis effect of nervous system

Answer 19

Increased excitability of PNS

Question 20

Chemical buffer systems

Answer 20

• Bicarbonate
• Phosphate
• Protein

Question 21

Line of Buffers

Answer 21

• Chemical
• Resp
• Renal

Question 22

More CO2 causes ______ bicarbonate

Answer 22

More, but also releases a acid

Question 23

Phosphate buffer

Answer 23

More for intra/extracellular fluid than for blood

Question 24

Protein buffers

Answer 24

• Includes hemoglobin
• Carboxyl group gets rid of H+
• Amino group accepts H+
• These side chains are present on 27 amino acids

Question 25

How the kidney works

Answer 25

• Can excrete either acids or bases

- Can produce bicarbonate

Question 26

Response time of resp system

Answer 26

Minutes to hours

Question 27

Response time of renal system

Answer 27

1-2 days

Question 28

Def of metabolic acid/alkalosis

Answer 28

Any cause other than resp

Question 29

Can cause costal breathing to dominate over diaphragmatic

Answer 29

• Exercise
• Abdominal pressures, fluids, or masses restrict movement
• Pain with deep breaths

Question 30

Accessory muscles of breathing

Answer 30

• Scalene
• SCM
• Pec minor
• SA
• Abdominal wall

Question 31

How do the accessory muscles increase depth of breathing?

Answer 31

• Scalene/SCM: raise upper ribs/sternum
• Pec min/SA: when scapula is fixed, lift the rib cage
• Abdominal wall: Push diaphragm superiorly

Question 32

Functions of the thoracic wall

Answer 32

• Protection
• Resist negative pressure of lungs
• Attachment + support of UE
• Muscle attachment

Question 33

Location of kidneys

Answer 33

Posterior abdominal wall, T12-L3

Question 34

What kidney is slightly higher

Answer 34

Right