export_resp 12

Question 1

ventilation

Answer 1

air exchange between atmosphere and alveoli

Question 2

what are the pulmonary defenses?

Answer 2

mucus, cilia, immune cells

Question 3

breakdown of airways

Answer 3

trachea - bronchi - bronchioles - terminal bronchioles - respiratory bronchioles - alveolar ducts - alveolar sacs

Question 4

where does gas exchange occur in the lungs?

Answer 4

respiratory bronchioles, alveolar ducts, alveolar sacs

Question 5

what secrete mucus?

Answer 5

goblet cells and mucus-secreting glands

Question 6

what cells secrete surfactant?

Answer 6

type II on alveoli

Question 7

pleural sac

Answer 7

double-walled structure surrounding each lung

Question 8

intrapleural space

Answer 8

• space between lung and thoracic wall

- contains intrapleural fluid

Question 9

elastic recoil

Answer 9

tendency for lungs to want to pull in

Question 10

transpulmonary pressure (Ptp)

Answer 10

difference in P between alveolar P and intraplural P

-pushed outward on lung wall

Question 11

transrespiratory pressure (Prs)

Answer 11

pressure diff between alveolar P and atmospheric P

-determines airflow

Question 12

transmural pressure across chest wall (Pcw)

Answer 12

P difference between intraplural P and atmospheric P

-F pushing on chest wall

Question 13

inspiratory muscles

Answer 13

diaphragm, external intercostals

Question 14

expiratory muscles (when not passive)

Answer 14

abs, internal intercostals

Question 15

how does diaphragm cause inspiration?

Answer 15

diaphragm contract –> inc thoracic volume –> dec thoracic P –> inspiration

Question 16

tests to measure lungs

Answer 16

• amount of air lungs can hold

- residual volume

Question 17

vital capacity

Answer 17

amount of air in lungs after max inhale and exhale

Question 18

tidal volume

Answer 18

amount of air inhaled/exhaled during relaxed breathing

Question 19

residual volume

Answer 19

amount of air in lungs after max expiration

-keeps alveoli inflated

Question 20

functional residual capacity

Answer 20

amount of air in lungs after relaxed expiration

Question 21

what is anatomic dead space?

Answer 21

volume in airways left over from preceding breath

Question 22

what type of breath increases alveolar ventilation?

Answer 22

deep breath

Question 23

tidal volume

Answer 23

volume per breath

Question 24

alveolar ventilation

Answer 24

tidal volume minus dead space

Question 25

alveolar dead space

Answer 25

no blood or air supply

Question 26

what determines volume of air moved during ventilation?

Answer 26

1) Ptp 2) compliance (lung elasticity) 2) airway resistance

Question 27

low lung compliance=

Answer 27

- stiff - difficult to expand - high surface tension (low surfactant)

Question 28

emphysema

Answer 28

-high compliance (floppy) lung

Question 29

what determines compliance?

Answer 29

1) elastic lung tissue | 2) surface tension

Question 30

what causes surface tension?

Answer 30

forces acting on water at surface of alveoli

Question 31

surfactant

Answer 31

- phospholipids and proteins - secreted by type II cells -lowers surface tension

Question 32

what determines airway resistance?

Answer 32

size of airway

Question 33

what determines flow rate?

Answer 33

- pressure | - resistance*

Question 34

as number of airways inc, total resistance ____

Answer 34

decreases (even though individual airways increase)

Question 35

why doesnt resistance limit air flow?

Answer 35

- lateral traction (pulled open when alveoli expand) | - pranspulm pressure (acts outward and pulls them open)

Question 36

what signals to airway resistance?

Answer 36

- inc parasymp and inflammation | - dec by CO2 and epinephrine

Question 37

when is resistance greatest?

Answer 37

expiration and low lung volumes

Question 38

what increases mucus secretion and airway contractions?

Answer 38

- parasym | - paracrines (hisamine)

Question 39

what causes airway dilation?

Answer 39

- epinephrine | - PCO2 in alveoli

Question 40

asthma effects

Answer 40

- elasticity - surface tension -resistance

Question 41

asthma therapies

Answer 41

- reduce inflammation | - bronchiodilators

Question 42

emphysema

Answer 42

- destroyed alveolar walls (dec surface area) - airway collapse - destroyed pulmonary capilalries - inc resistance (dec recoil and lateral traction)

Question 43

bronchitis

Answer 43

- excessive mucus - inflammation -inc resistance

Question 44

COPD

Answer 44

emphysema and bronchitis

Question 45

fibrosis

Answer 45

- inc connective tissue stiffens lungs - unable to expand alveoli - lung volumes dec - inc diffusion distance - R unchanges/slight dec