Map Lecture Exam Ii Resp 2

Front 1

What is the primary function of the respiratory system?

Back 1

gas exchange between air and circulating blood
• lungs - provide gas exchange "interface" between air & blood → supply body with O₂ and dispose of CO₂

Front 2

What is the secondary function of the respiratory system?

Back 2

acid-case balance (by regulating CO₂ in the blood)

Front 3

The respiratory system consists of ___ and ___ zones

Back 3

conducting and respiratory zones

Front 4

conducting zone

Back 4

from nasal cavity to terminal bronchioles "dead space"
• maintenance of open airway
• humidity
• adjust temperature
• cleanse

Front 5

respiratory zone

Back 5

respiratory bronchioles and alveoli
• site of gas exchange

Front 6

respiratory muscles

Back 6

diaphragm and other muscle that promote ventilation

Front 7

ANS regulates smooth muscle to control _____ diameter

Back 7

ANS regulates smooth muscle to control bronchiole diameter
• controls airflow & resistance in lungs

Front 8

bronchodilation

Back 8

controlled by SNS → reduces resistance

Front 9

bronchoconstriction

Back 9

controlled by PNS and histamine release (allergies) → increases resistance

Front 10

What is alveoli?

Back 10

air-filled pockets within lungs where gas exchange takes place
• ~300 million alveoli
• account for most of lung's volume
• provide tremendous surface area for gas exchange

Front 11

Alveoli are patrolled by _____ _____ (dust cells) - phagocytize microbes

Back 11

alveolar macrophages

Front 12

What are Type 1 cells?

Back 12

thin, delicate endothelial cells

Front 13

What are Type 2 cells?

Back 13

produce surfactant (oily secretion - coats epithelium & reduce surface tension)

Front 14

Surface tension

Back 14

caused by attraction of H₂O molecules to each other (collapses alveoli) (premature babies - immature Type 2 cells = little/no surfactant)

Front 15

Pulmonary capillaries

Back 15

exchange CO₂ and O₂ with alveoli
• capillaries surround alveoli

Front 16

Respiratory Membrane

Back 16

thin membrane of alveoli where gas exchange takes place (air-blood interface)

Front 17

What are the three layers that gases must diffuse across?

Back 17

1. Type 1 alveolar cells
2. Fused basal laminae between alveolar and endothelial cells
3. Endothelial cells of capillary

Front 18

Blood supply to the lungs: pulmonary circuit

Back 18

purpose is gas exchange (also nourishes respiratory membrane)

pulmonary arteries → pulmonary capillaries → pulmonary veins

Front 19

Blood supply to the lungs: systemic circuit

Back 19

purpose is to nourish lung tissue

Bronchial arteries → Bronchial capillaries → Pulmonary veins

Front 20

Each lung is located within a double-layers _____ membrane

Back 20

serous

Front 21

Visceral pleura

Back 21

lines outer lung surface

Front 22

Parietal pleura

Back 22

lines inner surface of thoracic wall

Front 23

Thoracic wall:

Back 23

• floor - diaphragm
• circumference - ribs & intercostals

Front 24

The right and left pleural cavities are separated by the _____

Back 24

mediastinum

Front 25

Each pleural cavity holds a long and lungs function ____

Back 25

independently

Front 26

pleural cavity

Back 26

holds serous fluid that reduces friction as lungs inflate/deflate

Front 27

What are the two principles affecting air movement?

Back 27

atmospheric pressure and Boyle's Law

Front 28

Atmospheric Pressure

Back 28

(Patm) ~ weight of the Earth's atmosphere (on our bodies and everything around us)

• affects air movement into and out of our lungs

• our lungs have their own pressure that varies between above and below atmospheric pressure as we breathe

Front 29

Respiratory Pressure

Back 29

is describe relative to Patm

• Negative respiratory pressure is pressure < Patm
• Positive respiratory pressure is pressure > Patm

Front 30

Boyle's Law

Back 30

defines the relationship between gas pressure and volume

↓ V of container:
• each molecule travels same distance within a time period
• hit wall more frequently
• molecules exert more pressure on container
• = ↑ P

Front 31

Respiratory cycle

Back 31

1 inspiration (inhalation) + 1 expiration (exhalation)

causes volume changes in thoracic cavity (with expansion or contraction of diaphragm or rib cage) that create changes in pressure

Front 32

Mechanics of Breathing

Back 32

based on pressure differences (△P) between air in lungs and atmosphere during on Respiratory Cycle

Front 33

What is the normal atmosphere pressure?

Back 33

1 atm at sea level = 760 mm Hg

Front 34

intra-alveolar pressure (Palv)

Back 34

pressure of the lungs (within alveoli)
• measured relative to atmosphere pressure

Front 35

During relaxed breathing ....

Back 35

inhalation = −1 mm Hg inside lungs
exhalation = +1 mm Hg inside lungs

Front 36

At rest ("Quiet" inspiration/expiration) the most important muscles are:

Back 36

diaphragm and external intracostal muscles of the ribs

Front 37

accessory respiratory muscles →

Back 37

activated only when respiration increases significantly ("forced" inspiration/exhalation)

Front 38

Quiet inspiration

Back 38

diaphragm and external intercostal muscles (inspiratory muscles) contract and the rib cages rises

Front 39

Quiet expiration

Back 39

inspiratory muscles relax and the rib cage descends due to gravity

Front 40

What are some physical properties of the lungs?

Back 40

elasticity, compliance, and airway resistance

Front 41

What is elasticity?

Back 41

stretching force
• inward recoil force of lungs due to elastic tissue and surface tension of fluid lining alveoli

Front 42

What is compliance?

Back 42

ease of expansion
• increase compliance → easier to expand lungs → decrease work of breathing

Front 43

What is airway resistance?

Back 43

depends of diameter of lungs

Front 44

Respiratory system adapts to changing oxygen demands by varying:

Back 44

• number of breaths per minute (respiratory rate) (

Front 45

respiratory rate

Back 45

number of breaths per minute
average = 12 breaths per minute

Front 46

tidal volume

Back 46

volume of air moved per breath (Vt)
average = 500 mL per breath

Front 47

Respiratory Minute Volume

Back 47

(VE) - amount of air moved per minute calculated by:

Front 48

Anatomical Dead Space

Back 48

volume of air that doesn't reach alveoli (air remaining in conducting passages - trachea, mouth, etc)

Front 49

Alveolar Dead Space

Back 49

if alveoli cease in gas exchange (e.g. damage or lined with mucus)

Front 50

Total Dead Space

Back 50

(Vd) = Anatomical Dead Space + Alveolar Dead Space

Front 51

Alveolar Ventilation (VA)

Back 51

amount of air reaching alveoli each minute
Calculated as:

Front 52

Measurements of airflow: Respiratory volumes

TV

Back 52

TV = volume of one breath

Front 53

Measurements of airflow: Respiratory volumes

IRV

Back 53

IRV = volume inhaled with maximum effort in excess of tidal volume

Front 54

Measurements of airflow: Respiratory volumes

ERV

Back 54

ERV = volume exhaled with max. effort in excess of tidal volume

Front 55

Measurements of airflow: Respiratory volumes

RV

Back 55

RV = volume remaining in lungs after max. expiration (keeps alveoli inflated)

Front 56

Measurements of airflow: Respiratory capacities

VC

Back 56

VC = volume exhaled with maximum effort after maximum inspiration

Front 57

Measurements of airflow: Respiratory capacities

IC

Back 57

IC = volume of air inhaled after normal tidal expiration

Front 58

Functional residual capacity

Back 58

Functional residual capacity = volume in lungs after normal tidal expiration

Front 59

Total lung capacity

Back 59

Total lung capacity = maximum volume lungs can contain

Front 60

VC =

Back 60

ERV + TV + IRV

Front 61

IC =

Back 61

TV + IRV

Front 62

Functional residual capacity =

Back 62

ERV + RV

Front 63

Total lung capacity =

Back 63

VC + RV

Front 64

Pulmonary function tests

Back 64

used to asses one's respiratory status (compared with "normal" values)

Front 65

spirometer

Back 65

instrument used to measure different volumes of breathed air (water is displaced by the breathed air, and the volume can be recorded)

Helpful in distinguishing obstructive or restrictive disorders

Front 66

Obstructive disorder

Back 66

difficult to get air out of the lungs (expiration)
• emphysema, bronchitis, and asthma

Front 67

Restrictive disorder

Back 67

difficult to get air into the lungs (inhalation)
• mascular diseases, chest wall deformities

Front 68

Gas exchange occurs between air in ____ & ____

Back 68

alveoli & blood → across respiratory membrane

Front 69

Gases are exchange by diffusion in response to a ____ ____

Back 69

concentration gradient

Front 70

To understand how gases are exchanged between air in alveoli & blood you will need to consider:

Back 70

1. Partial pressure of gases (Dalton's Law)
2. Diffusion of molecules between gas & a liquid (Henry's Law)

Front 71

Dalton's Law of Partial Pressure (PP)

Back 71

• Total pressure (of gas mixture) = sum of individual gas pressures... called the partial pressures
• The partial pressure of each gas is directly proportional to its percentages in the mixture
Partial pressure (PO₂, PCO₂ is the driving force for diffusion of gases
• Gases diffuse from high to low pressure (down their own concentration gradient)
Composition of Air:
Nitrogen ~ 78.6%
Water vapor ~ 0.5%
Oxygen ~ 20.9%
Carbon dioxide ~0.04%
Atmospheric Pressure = 760 mm Hg
Each gas above contributes to the total pressure → in proportion to its number of molecules (or its partial pressure)
All partial pressure of molecules in air together add up to 760 mm Hg (atm pressure)

Front 72

If you have a container with 4 gases:
50% CO₂
25% O₂
12.5% N₂
12.5% CH₄

Total pressure in the container at: 800 mm Hg

According to Dalton's Gas Law; what is the partial pressure of CO₂, O₂?

Back 72

CO₂ = 400 mm Hg
O₂ = 200 mm Hg
N₂ = 100 mm Hg
CH₄ = 100 mm Hg

Front 73

Henry's Law of Dissolves Gases

Back 73

• When the mixture of gases is in contact with a liquid, each gas will dissolve in the liquid in proportion to its partial pressure
• The greater the concentration of a particular gas → the faster it will go into solution
• At equilibrium - partial pressure in 2 phases (gas & liquid) are equal

Front 74

Forced Exhalation includes respiratory accessory muscles such as:

Back 74

internal intercostals and abdominal muscles

Front 75

Force Inhalation includes accessory accessory respiratory muscles such as:

Back 75

Sternocleidomastoid & scalenes and Pectoralis minor and serratus anterior