Ch 23 Lecture Respiratory System

Front 1

The Respiratory System

Back 1

Supplies O2 to blood and gets rid of CO2

Front 2

The Respiratory System consists of

Back 2

–Nose and nasal cavity
–Throat (pharynx)
–Voice box (larynx)
–Windpipe (trachea)
–Bronchial tubes
–Lungs

Front 3

The Respiratory System

Back 3

Front 4

Functions of Respiratory System

Back 4

•Cleaning and humidifying air
•Ventilation
•Gas exchange
•Gas transport
•Smell
•Speech

Front 5

Pulmonary Lobule

Back 5

Front 6

Pulmonary Lobule

Back 6

-Small compartments within lungs
-Separated by elastic connective tissue

Front 7

Pulmonary Lobule Consist of:

Back 7

-Terminal bronchiole supplies air to lobule
-Several branches of terminal bronchiole called respiratory bronchioles
-Branches of respiratory bronchioles called alveolar ducts supply air to alveolar sacs
-Alveolar sacs consist of several bubble-like chambers called alveoli (alveolus) where most gas exchange with blood occurs
-Blood supply

Front 8

Terminal bronchiole

Back 8

supplies air to lobule

Front 9

Several branches of terminal bronchiole called

Back 9

respiratory bronchioles

Front 10

respiratory bronchioles

Back 10

first part of lungs capable of gas exchange

Front 11

Branches of respiratory bronchioles called

Back 11

alveolar ducts supply air to alveolar sacs

Front 12

Alveolar sacs consist of several bubble-like chambers called

Back 12

alveoli (alveolus) where most gas exchange with blood occurs

Front 13

Pulmonary Lobule with Alveolar Sac

Back 13

Front 14

Pulmonary Lobule

Back 14

Front 15

Pulmonary Lobule

Back 15

Front 16

Details of Alveolar Structure

Back 16

Front 17

Respiratory Membrane (RM)

Back 17

gas exchange

Front 18

Respiratory Physiology

Back 18

•Ventilation
•Control of Ventilation
•Gas Exchange
•Gas Transport
•Carbon dioxide transport

Front 19

Ventilation
•Basic concepts and definitions

Back 19

–Breathing in is called inhalation or inspiration
–Breathing out is called exhalation or expiration

Front 20

Breathing in is called

Back 20

inhalation or inspiration

Front 21

Breathing out is called

Back 21

exhalation or expiration

Front 22

Inhalation

Back 22

Contraction of diaphragm and rib muscles (ext. intercostals) enlarges chest

Front 23

Inhalation

Back 23

Reduces intrapulmonary pressure to below (negative to) atmospheric pressure

Front 24

Inhalation

Back 24

Air flows into lungs

Front 25

Exhalation

Back 25

Diaphragm and rib muscles (ext. Intercostals) relax

Front 26

Exhalation

Back 26

Chest gets smaller

Front 27

Exhalation

Back 27

Elastic recoil of chest and lungs, and contraction of certain muscles

Front 28

Exhalation

Back 28

Increases intrapulmonary (lung) pressure to above (positive to) atmospheric pressure

Front 29

Exhalation

Back 29

Air is pushed (squeezed) out of lungs

Front 30

Ventilation Explained by Boyle’s Law

Back 30

•Boyle’s Law
–As size of container increases, pressure inside decreases
–As the size of container decreases, pressure inside is increases

Front 31

Ventilation Explained by Boyle’s Law

Back 31

Front 32

Ventilation Cycle – Between Breathes

Back 32

Front 33

Inhalation

Back 33

Front 34

Exhalation

Back 34

Front 35

Resting Ventilation

Back 35

Eupnea

Front 36

Inhalation is active

Back 36

–Diaphragm and external intercostal muscles expand chest and lungs
–Intrapulmonary pressure decreases to below atmospheric pressure
–Air flows into lungs

Front 37

Exhalation is passive

Back 37

–Diaphragm and external intercostal muscles relax
–Chest volume decreases
–Elastic recoil of lungs increases intrapulmonary pressure to above (positive to) atmospheric pressure
–Air flows out of lungs

Front 38

Forced inhalation and exhalation

Back 38

Must be larger change in chest and lung volumes resulting in larger changes in intrapulmonary pressure

Front 39

Forced inhalation and exhalation

Back 39

Other muscles become involved resulting in deeper inhalation followed by more forceful exhalation

Front 40

Forced inhalation and exhalation

Back 40

Muscles not only expand chest on inhalation, they compress chest on exhalation

Front 41

Respiratory Volumes and Capacities

Back 41

•Volume is one measure of quantity of air
•Capacity is sum of two or more volumes
•Spirometer or respirometer device for measuring volumes and capacities
•Record called spirogram

Front 42

Volume

Back 42

is one measure of quantity of air

Front 43

Capacity

Back 43

is sum of two or more volumes

Front 44

Spirometer or respirometer device

Back 44

for measuring volumes and capacities

Front 45

Record

Back 45

called spirogram

Front 46

Ventilation Rates and Volumes

Back 46

•Ventilation rate is number of breaths per minute
•Resting ventilation rate is 12-18 breaths per minute
•Tidal volume (TV) or (VT) is amount of air in one breath
•Resting tidal volume is around 500 mL

Front 47

Ventilation rate is

Back 47

number of breaths per minute

Front 48

Resting ventilation rate is

Back 48

12-18 breaths per minute

Front 49

Tidal volume (TV) or (VT) is

Back 49

amount of air in one breath

Front 50

Resting tidal volume is

Back 50

around 500 mL

Front 51

Respiratory Minute Volume

Back 51

–If rate = 12 breaths per minute
–And Tidal volume (VT) = 500 mL per minute
–Then respiratory minute volume =

Front 52

Ventilation Rates and Volumes

Back 52

•If resting tidal volume (VT) = 500 mL, then
•Alveolar Ventilation (VA)
–350 mL reaches alveoli
–Participates in gas exchange

Front 53

Anatomic Dead Space or Air (VD)

Back 53

–150 mL remains in conducting airways above alveoli
–This air does not participate in gas exchange
–Is mixture of fresh inhaled air and air to be exhaled

Front 54

Inspiratory Reserve Volume (IRV)

Back 54

–Additional volume that can be inhaled with maximum effort after the tidal volume.
–Might be more than 3 liters
–Provides more inhaled air when active

Front 55

Expiratory Reserve Volume (ERV)

Back 55

–Additional volume that can be exhaled after the tidal volume
–Might be around 1liter

Front 56

Residual Volume (RV)

Back 56

–Volume that cannot be exhaled
–Lungs must remain inflated
–Might be around 1 liter

Front 57

Vital Capacity (VC)

Back 57

–Maximum amount of air inhaled and exhaled in one respiratory cycle
–VC = VT + IRV + ERV

Front 58

Spirogram

Back 58