Jackson 1

Question 1

Lungs Regulate

Answer 1

blood pH

ventilation rate affects amount of CO2 in plasma

Question 2

Lungs Provide microbial defense by means of

Answer 2

epithelial secretions –

lymphoid tissue in tract –

coughing and sneezing reflexes –

Question 3

Lungs

6. Activate (or inactivate)

Answer 3

chemical messengers in blood –

e.g. convert angiotensin I to angiotensin II

Question 4

Lungs 7. Defend against

Answer 4

blood clots – small blood clots get trapped in narrow vessels in lungs and are dissolved

Question 5

Components and zones of the respiratory system

Answer 5

airways – series of tubes needed to exchange air between lungs and environment

lungs – site of gas exchange between air and blood

mechanical aids – skeletal muscles used to vary the volume of the thoracic cavity

Question 6

upper airway – structures are

Answer 6

outside of the thoracic cavity

mouth/nose → pharynx → larynx → top of trachea

Question 7

2. conducting zone –

Answer 7

in thoracic cavity, but no gas exchange occurs

trachea → primary bronchi → secondary bronchi → tertiary bronchioles → bronchioles → terminal bronchioles

trachea and bronchi include cartilaginous rings and mucous glands –

bronchioles lose cartilage and glands, but add smooth muscle

Question 8

respiratory zone – structures where

Answer 8

gas exchange can occur

respiratory bronchioles → alveolar ducts → alveolar sacs

Question 9

respiratory bronchioles very

Answer 9

thin-walled; have alveoli in walls

Question 10

Branching creates

Answer 10

parallel airways to maintain airflow and minimize increasing resistance to airflow. Compare this set-up to one in which multiple tubes simply become narrower.

Question 11

Air is warmed and moistened – heat and water vapor are

Answer 11

exchanged with the blood in airway walls

Question 12

Conducting zone protects against

Answer 12

microbes

Question 13

goblet cells secrete mucus which can

Answer 13

trap airborne particles and pathogens;

Question 14

cilia on epithelial cells move

Answer 14

mucus upwards to pharynx where it can be swallowed or expelled

Question 15

Closed pneumothorax:

Answer 15

Pleural cavity pressure less than ATM

Question 16

Open pneumothorax:

Answer 16

pleural cavity pressure = atm

Question 17

tension pneumothorax:

Answer 17

pleural cavity pressure > ATM

Question 18

Cystic fibrosis is a disease that

Answer 18

impairs the normal function of the conducting zone

Question 19

Cystic fibrosis: mutation in genetic code for

Answer 19

Cl- channel reduces the amount of Na+ and Cl- secreted across the epithelium into mucus. This leads to there being less water in the mucus (due to osmosis)→ mucus is thick and dry

Question 20

Cystic fibrosis: consequences of abnormal mucus -

Answer 20

infectious agents are trapped, but not expelled; airways are obstructed

Question 21

Airflow is regulated by

Answer 21

bronchiolar smooth muscle

Question 22

——- in alveoli provides time for exchange –

Answer 22

low rate of bloodflow

Question 23

Microbial defense is provided by

Answer 23

pulmonary macrophage

Question 24

Type I –

Answer 24

epithelial; gas exchange surface

Question 25

Type II –

Answer 25

secrete surfactant

Question 26

Macrophages – are considered the

Answer 26

3rd alveoli cells??

Question 27

alveolar sacs are

Answer 27

~0.5 μm in diameter

Question 28

distance between alveolus and capillary

Answer 28

≈ 0.2 μm

Question 29

Respiratory gases are small non-polar molecules that diffuse down a “concentration” gradient - diffuse easily through plasma membranes, less easily through

Answer 29

body fluids

Question 30

CO2 solubility = 77 mmol/L;

Answer 30

77 mmol/L;

Question 31

O2 solubility =

Answer 31

2.2 mmol/L

Question 32

Intrapleural fluid fills sacs (—– thick

Answer 32

10 – 20 μm thick)

Question 33

Air flow is a function of the

Answer 33

pressure gradient and the resistance to flow within the airways

Question 34

F =

Answer 34

ΔP/R
In the respiratory system, the pressure difference (ΔP) of concern is the difference between gas pressure in the lung/alveoli and atmospheric pressure (Palv - Patm )

Question 35

If Palv < Patm, air flows

Answer 35

into lung (inspiration)

Question 36

If Palv > Patm, air flows

Answer 36

out of lung (expiration)

Question 37

Alveolar pressure changes in response to

Answer 37

changing the volume of the lungs according to Boyle’s Law

(P1 V1 = P2 V2 ),

Question 38

transpulmonary (Ptp) =

Answer 38

Palv - Pip (Pip = interpleural pressure)

Question 39

diaphragm contracts →

Answer 39

lowers floor of cavity → increases volume - inhale

Question 40

external intercostals contract →

Answer 40

raise ribcage → increase volume - inhale

Question 41

diaphragm relaxes →

Answer 41

raises floor of cavity → reduces volume - exhale.

Question 42

external intercostals relax /internal intercostals contract→

Answer 42

lower ribcage → reduces volume - exhale

Question 43

Palv equal Patm

Answer 43

between breaths (no air is moving)

Question 44

Pip below

Answer 44

atmospheric pressure between breaths

Question 45

Ptp = Palv – Pip;

Answer 45

lungs remain expanded
lungs tend to recoil inward –

chest wall tends to recoil outward –

net result is Pip is always subatmospheric

Question 46

During inspiration – diaphragm

Answer 46

contracts → thorax expands

Question 47

During inspiration:

Pip becomes

Answer 47

more negative

Question 48

During inspiration: Ptp

Answer 48

increases so lung volume increases and air flows in until Palv = Patm

Question 49

During expiration - diaphragm

Answer 49

relaxes → thorax compresses

Question 50

During expiration: Pip becomes

Answer 50

less negative

Question 51

During expiration: Ptp

Answer 51

decreases so lung volume decreases and air flows out until Palv = Patm