GAS EXCHANGE Cardio Respiratory System
description
Transcript of GAS EXCHANGE Cardio Respiratory System
GAS EXCHANGECardio Respiratory
System
GAS EXCHANGE
1. supplies oxygen for aerobic cellular respiration (reactant)
2. removes carbon dioxide from aerobic cellular respiration (product)
3. Must carry out ventilation - actively moving air in and out of body surfaces
4. Terrestrial – gases in air Aquatic – gases dissolved in water
Fig. 42-2
Circularcanal
Radial canalMouth
(a) The moon jelly Aurelia, a cnidarian The planarian Dugesia, aflatworm
(b)
MouthPharynx
2 mm5 cm
SOME AQUATIC INVERTEBRATES: Thin-wall - Gases diffuse through the membrane
Fig. 42-21
Parapodium (functions as gill)(a) Marine worm
Gills
(b) Crayfish (c) Sea star
Tube foot
Coelom
Gills
OTHER AQUATIC INVERTIEBRATES USE GILLS
Fig. 42-23
Air sacs
Tracheae
Externalopening
Bodycell
AirsacTracheole
Tracheoles Mitochondria Muscle fiber
2.5 µmBody wall
Trachea
Air
Arachnids (Spiders/Scorpians) - Book Lungs
Fig. 42-22
Anatomy of gills
Gillarch
Waterflow Operculum
Gillarch
Gill filamentorganization
Bloodvessels
Oxygen-poor blood
Oxygen-rich blood
Fluid flowthrough
gill filament
Lamella
Blood flow throughcapillaries in lamella
Water flowbetweenlamellae
Countercurrent exchange
PO2 (mm Hg) in water
PO2 (mm Hg) in blood
Net diffu-sion of O2
from waterto blood
150 120 90 60 30
110 80 20Gill filaments
50140
GILLS
Fig. 42-UN4
GAS EXCHANGE THROUGH SKIN ONLY SKIN LUNGS
SKIN ONLY
SNAKE RESPIRATORY
REPTILES
DINOSAUR BIRD BONES
Fig. 42-26
Anteriorair sacs
Posteriorair sacs Lungs
Air
Lungs
Air
1 mm
Trachea
Air tubes(parabronchi)in lung
EXHALATIONAir sacs empty; lungs fill
INHALATIONAir sacs fill
LUNGS
Fig. 42-25
Lung
Diaphragm
Airinhaled
Rib cageexpands asrib musclescontract
Rib cage getssmaller asrib musclesrelax
Airexhaled
EXHALATIONDiaphragm relaxes
(moves up)
INHALATIONDiaphragm contracts
(moves down)
Air Volume
Fig. 42-27
Breathingcontrolcenters
Cerebrospinalfluid
Pons
Medullaoblongata
Carotidarteries
Aorta
DiaphragmRib muscles
Fig. 42-UN2Inhaled air Exhaled air
Alveolarepithelial cells
Alveolar spaces
CO2 O2
CO 2 O2
Alveolarcapillaries of
lung
Pulmonary veinsPulmonary arteries
Systemic veins Systemic arteries
Heart
SystemiccapillariesCO
2 O 2
CO2 O2
Body tissue
Fig. 42-28Alveolus
PO2 = 100 mm Hg
PO2 = 40 PO2
= 100
PO2 = 100PO2
= 40
Circulatorysystem
Body tissuePO2
≤ 40 mm Hg PCO2 ≥ 46 mm Hg
Body tissue
PCO2 = 46 PCO2
= 40
PCO2 = 40PCO2
= 46
Circulatorysystem
PCO2 = 40 mm Hg
Alveolus
(b) Carbon dioxide(a) Oxygen
Fig. 42-UN1
Chains
IronHeme
ChainsHemoglobin
HEMOGLOBIN
OXYGEN EXCHANGE
Fig. 42-29a
O2 unloadedto tissuesat rest
O2 unloadedto tissues
during exercise
100
40
0
20
60
80
0 40 80 100
O2 s
atur
ation
of h
emog
lobi
n (%
)
20 60
Tissues duringexercise
Tissuesat rest
Lungs
PO2 (mm Hg)
(a) PO2 and hemoglobin dissociation at pH 7.4
Fig. 42-29b
O2 s
atur
ation
of h
emog
lobi
n (%
)
40
0
20
60
80
0 40 80 10020 60
100
PO2 (mm Hg)
(b) pH and hemoglobin dissociation
pH 7.4pH 7.2
Hemoglobinretains lessO2 at lower pH(higher CO2
concentration)
Fig. 42-UN3
Fetus
Mother
100
80
60
40
20
00 20 40 60 80
O2 s
atur
ation
of
hem
oglo
bin
(%)
100
PO2 (mm Hg)
Fig. 42-30aBody tissue
CO2 produced
CO2 transportfrom tissues
Interstitialfluid CO2
CO2
CO2
Plasmawithin capillary
Capillarywall
H2O
H2CO3
Carbonic acid
Redbloodcell
Hemoglobinpicks up
CO2 and H+Hb
H+HCO3–
Bicarbonate+
HCO3–
To lungs
Fig. 42-30b
HCO3–
HCO3– H++
CO2 transportto lungs
Hemoglobinreleases
CO2 and H+HbH2CO3
H2O
CO2
Plasma withinlung capillary
CO2
CO2
CO2
Alveolar space in lung
CARBON DIOXIDE