Download Respiration

Respiration
 Respiration

Physiological process by which oxygen
moves into an animal’s internal environment
and carbon dioxide moves out
 Aerobic



respiration
Cellular process, produces ATP
Oxygen is used
Carbon dioxide is produced
Respiratory System
 Works
with the circulatory system to
deliver oxygen and remove carbon
dioxide
 Also helps regulate acid-base balance
Pressure Gradients
 Concentration
gradients for gases
 Gases diffuse down their pressure
gradients
 Gases enter and leave the body by
diffusing down pressure gradients across
respiratory membranes
Factors In Gas Exchange
 Surface-to-volume

ratio
Small, flat animals
 Ventilation

Adaptations enhance exchange rate
 Respiratory

pigments
Hemoglobin and myoglobin
Surface-to-Volume Ratio
 As
animal size increases, surface-tovolume ratio decreases
 Small,
flat animals can use the body
surface as their respiratory surface
 Larger
animals have special structures to
increase respiratory surface, such as gills
or lungs
The main function of the
respiratory system is _____.
1.
2.
3.
4.
gas exchange
breathing
energy production
transportation of
oxygen to tissues
0%
1
0%
2
0%
3
0%
4
Respiratory Surfaces
 In
flat animals
CO2
O2
Respiration
 Respiration

Physiological process by which oxygen
moves into an animal’s internal environment
and carbon dioxide moves out
 Aerobic



respiration
Cellular process, produces ATP
Oxygen is used
Carbon dioxide is produced
Respiratory System
 Works
with the circulatory system to
deliver oxygen and remove carbon
dioxide
 Also helps regulate acid-base balance
Pressure Gradients
 Concentration
gradients for gases
 Gases diffuse down their pressure
gradients
 Gases enter and leave the body by
diffusing down pressure gradients across
respiratory membranes
Factors In Gas Exchange
 Surface-to-volume

ratio
Small, flat animals
 Ventilation

Adaptations enhance exchange rate
 Respiratory

pigments
Hemoglobin and myoglobin
Surface-to-Volume Ratio
 As
animal size increases, surface-tovolume ratio decreases
 Small,
flat animals can use the body
surface as their respiratory surface
 Larger
animals have special structures to
increase respiratory surface, such as gills
or lungs
The main function of the
respiratory system is _____.
1.
2.
3.
4.
gas exchange
breathing
energy production
transportation of
oxygen to tissues
0%
1
0%
2
0%
3
0%
4
Respiratory Surfaces
 In
flat animals
CO2
O2
In the respiratory cycle, the main
muscles used are the _____.
1.
2.
3.
4.
intercostal and
diaphragm
pharynx and
larynx
bronchiole and
alveoli
oral and pleural
0%
1
0%
2
0%
3
0%
4
Fish Gills
 Usually
internal
 Water is drawn in
through mouth and
passed over gills
water
flows in
through
mouth
FISH GILL
water flows
over gills,
then out
FISH GILL
water
flows into
mouth a
mouth
closed
mouth
open
water flows
over gills,
then out.
lid
open
lid
closed
b
c
respiratory
surface
gill arch
gill
filament
direction
of water
flow
d
e
oxygenated
blood back
toward body
direction
of blood
flow
oxygen-poor
blood from
deep in body
Fig. 22-18, p.372
Countercurrent Flow


Blood flows in the
opposite direction of
water flow over the
filaments
Enhances movement
of oxygen from water
to blood
respiratory surface
direction of
water flow
oxygenated blood
back toward body
direction of
blood flow
oxygen-poor blood
from deep in body
Vertebrate Lungs

Originated in some
fishes as
outpouching from gut
wall

Allow gas exchange
in air and in oxygenpoor aquatic habitats
salamander
reptile
Avian Respiration
 Lungs
are
inelastic and
connect to a
series of air sacs
 Air is drawn
continually
though each
lung
air
sacs
air
sacs
lungs
air
sacs
Mammals
Mammal
Human; adapted
to dry habitats
Fig. 22-20c, p.373
Lungs are the only respiratory organs in all
of the following animals, except _____.
1.
2.
3.
4.
reptiles
birds
mammals
amphibians
0%
1
0%
2
0%
3
0%
4
In addition to gas exchange, the
respiratory system also _____.
1.
2.
3.
4.
helps blood in veins
return to the heart
helps dispose of
excess heat and
water
helps maintain acidbase balance
all of the choices
0%
1
0%
2
0%
3
0%
4
Human Respiratory System
pharynx (throat)
epiglottis
larynx (voice box)
trachea (windpipe)
pleural membrane
Bronchiole
Alveoli
intercostal muscle
diaphragm
NASAL CAVITY
ORAL CAVITY
(MOUTH)
PHARYNX (THROAT)
EPIGLOTTIS
LARYNX (VOICE BOX)
PLEURAL
MEMBRANE
INTERCOSTAL MUSCLES
TRACHEA (WINDPIPE)
LUNG (ONE OF A PAIR)
BRONCHIAL TREE
DIAPHRAGM
Fig. 22-21a, p.374
bronchiole
alveolar sac
(sectioned)
alveolar duct
alveoli
Fig. 22-21b, p.374
alveolar sac
pulmonary
capillary
Fig. 22-21c, p.374
Speech Production
 Vocal
cords stretch
across laryngeal
opening; opening
between them is
glottis
 Position of cords is
varied to create
different sounds
vocal cords
glottis (closed)
epiglottis
tongue’s base
Fig. 22-22a, p.375
glottis closed
glottis open
Fig. 22-22b, p.375
Breathing
 Moves
air into and out of lungs
 Occurs in a cyclic pattern called the
respiratory cycle
 One respiratory cycle consists of
inhalation and exhalation
Inhalation





Diaphragm flattens
External intercostal
muscles contract
Volume of thoracic
cavity increases
Lungs expand
Air flows down pressure
gradient into lungs
Normal (Passive) Exhalation

Muscles of inhalation
relax
 Thoracic cavity
recoils
 Lung volume
decreases
 Air flows down
pressure gradient
and out of lungs
INWARD
BULK FLOW
OF AIR
b Inhalation. The
diaphragm
contracts, moves
down. External
intercostal
muscles contract
and lift rib cage
upward and
outward. The lung
volume expands.
OUTWARD
BULK FLOW
OF AIR
c Exhalation.
Diaphragm,
external
intercostal
muscles return
to resting
positions. Rib
cage moves
down. Lungs
recoil
Fig.passively.
22-23, p.376
Active Exhalation

Abdominal and internal intercostal muscles
contract

Contraction decreases thoracic cavity volume
more than passive exhalation

Greater volume of air flows out to equalize
intrapulmonary pressure with atmospheric
pressure
In the respiratory cycle, the main
muscles used are the _____.
1.
2.
3.
4.
intercostal and
diaphragm
pharynx and
larynx
bronchiole and
alveoli
oral and pleural
0%
1
0%
2
0%
3
0%
4
Cutaway View of Alveolus
red blood cell
air space
inside
alveolus
(see next slide)
pore for airflow
between alveoli
Respiratory Membrane
 Area
between an
alveolus and a
pulmonary capillary
and
carbon dioxide
diffuse across
easily
alveolar
epithelium
capillary
endothelium
 Oxygen
fused
basement
membranes
of both
epithelial
tissues
Oxygen Transport
 Most
oxygen is bound to heme groups
in hemoglobin in red blood cells
 Hemoglobin has higher affinity for
oxygen when it is at high partial
pressure (in pulmonary capillaries)
 Lower affinity for oxygen in tissues,
where partial pressure is low
Bicarbonate Formation
CO2 + H2O
HCO3– + H+
H2CO3
carbonic acid
bicarbonate
• Most carbon dioxide is transported
as bicarbonate
• Some binds to hemoglobin
• Small amount dissolves in plasma
Control of Breathing
 Nervous
system controls rhythm and
magnitude of breathing
 Breathing is adjusted as a result of
changes in



Carbon dioxide levels
Oxygen levels
Blood acidity
Oxygen that enters the pulmonary capillaries
of the lungs is bound and transported by
_____.
1.
2.
3.
4.
hemoglobin
platelets
plasma
carbon dioxide
0%
1
0%
2
0%
3
0%
4
Bronchitis
 Irritation
of the ciliated epithelium that
lines bronchiole walls
 Caused
by air pollutants, smoking, or
allergies
 Excess
mucus causes coughing, can
harbor bacteria
 Chronic
airways
bronchitis scars and constricts
Emphysema
 Irreversible
breakdown of lung tissue
 Lungs become inelastic
 May be caused by a genetic defect
 Most often caused by smoking
Emphysema
Effects of Smoking





Shortened life expectancy
Increased rate of cancers
Increased rate of heart disease
Impaired immune function and
healing
Harmful to fetus
Smokers increase their risk of
_____.
1.
2.
3.
4.
heart attack
stroke
breast cancer
all of the choices
0%
1
0%
2
0%
3
0%
4