Transcript Respiration and Circulation Part 1 - Cal State LA

Respiration and
Circulation
Biology 155
A. Russo-Neustadt
Respiration
and
Circulation
are coupled
processes in
most animals
The systems
function
together to
exchange gases
with the
environment
and transport
them to the
tissues
I.
Types of Respiratory Exchange “Organs”:
A.
The Body Surface –
1.
Requires no respiratory system
2.
Animal must be small or thin
3.
Must have low oxygen /energy requirements
4.
Diffusion alone accounts for gas exchange
Oxygen
Carbon
Dioxide
Animals who use their body surface for
respiratory exchange include




Sponges
Jellyfish
Flatworms (previous slide)
Sea stars
B. Gills –
1. Evaginations
from the body
surface
(In mouth to oral
cavity over gills and
out slit)
2. Used by
aquatic
animals
Gill arch
Muscles in oral cavity
serve as pump for oneway water flow, due to
density of water
Animals who use gills for respiratory
exchange include




Marine worms
Clams and mussels
Lobsters and shrimp
Vertebrate fishes
(previous slide)
C. “Lungs”
Used by terrestrial animals
 Invaginations from the body surface to
decrease water loss
 Two major types –

lungs – used by snails and slugs,
vertebrates from amphibians to mammals
 Tracheal system of insects
 True
a. True lungs –
localized
exchange
surface where
oxygen is
loaded into the
bloodstream
Carbon
dioxide
oxygen
Trachea with
cartilaginous
rings
alveolus
lung
bronchus
Bronchial
tree
Ventilation uses tidal flow of air due to density
b. Trachea = system
of air filled tubes
that branches
throughout body
Note unique uncoupling between
respiratory and circulatory systems
Tracheole
delivers
oxygen to
individual
cells
D. All Respiratory Systems have the
Following Things in Common –
Large surface area to maximize gas
exchange
 Thin exchange surfaces to maximize the
rate of gas exchange

D. All Respiratory Systems have the
Following Things in Common –
continued

Gills and true lungs are also –
 Ventilated = use muscle pumps to keep
oxygen rich medium in contact with the
exchange surface
 Perfused = use muscle pumps to move blood
through the vessels at the exchange surface
to keep oxygen depleted blood in contact with
the exchange surface
 Together these processes ensure a large
concentration gradient for oxygen diffusion
II. Circulation:
A. Components-
1. The
cardiovascular
system = heart +
blood vessels
Function =
Circulates the
blood to and from
the tissues
8
Superior
vena cava
Capillaries of
head, chest, and
arms
Pulmonary
artery
Pulmonary
artery
Capillaries
of right lung
9
Capillaries
of left lung
Aorta
2
7
2
3
3
4
5
10
4
Pulmonary
vein
Right atrium
6
1
9
Pulmonary
vein
Left atrium
Left ventricle
Right ventricle
Inferior
vena cava
Aorta
8
Capillaries of
abdominal region
and legs
Right
atrium
To lung
To lung
Left atrium
From lung
From lung
Semilunar
valve
Semilunar
valve
Atrioventricular
(AV) valve
Atrioventricular
(AV) valve
Right
ventricle
Left
ventricle
2. The
lymphatic
system =
lymph vessels
+ lymph
nodes
Functions –
-immune defense
- returns some
fluid from the
tissues
Return of excess
fluid from the
tissues via the
immune system
B. Functions of the Circulatory
System
1.
2.
3.
Transport – oxygen, carbon dioxide,
nutrients, wastes and hormones in blood
Blood clotting – to seal breaks in vessels,
uses platelets and clotting proteins
Protection – internal defense using the
white blood cells and the lymphatic
system
C. Types of Circulatory Systems
1.
None –
Only used by small animals and/or those
with low rates of oxygen use
b. Circulation occurs due to simple diffusion
through the body tissues
a.
Examples of Animals That Lack a
Circulatory System




sponges (not shown)
jellyfish
flatworms
sea stars
2.
Few
vessels
Blood leaves vessels, loses
pressure, thus low flow, low
oxygen demand system
(Pump)
(Tissue sinuses)
Few
vessels
3.
Blood stays in
vessels, thus
(pump)
high pressure,
high flow
system for
high oxygen
demand
large vessels
(veins)
large vessels
(arteries,
arterioles)
Capillaries in
tissues for
exchange
Examples of Animals with an Open
Circulatory System



clams
Crayfish, shrimp,
lobsters (not shown)
insects as exception
to low oxygen use
rule (remember the
tracheal system)
Examples of Animals with a Closed
Circulatory System

vertebrates from fish
to mammals
D. The Vertebrate Circulatory
System 1.
Blood consists of–
Plasma = fluid with dissolved substances
(examples – nutrients, hormones and most
carbon dioxide)
b. Cells and cell fragments –
a.
1)
2)
3)
White blood cells – defense
Red blood cells – oxygen transport
Platelets – blood clotting
2. Vertebrate hearts and
circulatory patterns Note that the evolution of the fourchambered heart of the mammals and
birds allows blood to be returned to the
heart after exchanging gases at the lungs
and to be pumped a second time before
traveling to the tissues, needed for high
oxygen demand associated with high body
temperatures
(Pressure declines)
CO2
O2
O2
aorta
Pulmonary
artery
aorta
Left atrium
arteries
Pulmonary
vein
Right
atrium
Right ventricle
CO2
Atrium = receiving
chamber
Ventricle = pump
Vena cava
Vena cava
CO2
O2
O2
Mammals and
And thus blood is pumped twice for a
higher pressure, higher flow system
CO2
Two-chambered heart
with blood pumped
once; lower pressure,
lower flow system
23.4 The heart contracts and relaxes
rhythmically
 During
–
–
From veins
Into heart chambers
 During
–
–
diastole, blood flows
systole, blood flows
From atria
Into ventricles
Copyright © 2009 Pearson Education, Inc.
1
Heart is
relaxed.
Semilunar
valves
closed
AV valves
are open.
0.4 sec
Diastole
2
1
Heart is
relaxed.
Semilunar
valves
closed
Atria
contract.
0.1 sec
Systole
AV valves
are open.
0.4 sec
Diastole
2
1
Heart is
relaxed.
Semilunar
valves
closed
Atria
contract.
0.1 sec
Systole
AV valves
are open.
0.4 sec
0.3 sec
3
Ventricles
contract.
Semilunar
valves
are open.
Diastole
AV valves
closed
3. Generation of
the heart beat –
note that all
cardiac cells are
autorhythmic and
contract on their
own
Electrical signals
= action potentials
pass due to
intercalated discs
Pacemaker
(fastest rate of
contraction) =
(Holds signal
before passing to
ventricles,
connective tissue
between atria and
ventricles prevents
immediate passage
of signal