Transcript Document

Copyright Notice!
This PowerPoint slide set is copyrighted by Ross Koning
and is thereby preserved for all to use from
plantphys.info for as long as that website is available.
Images lacking photo credits are mine and, as long as
you are engaged in non-profit educational missions, you
have my permission to use my images and slides in your
teaching. However, please notice that some of the images
in these slides have an associated URL photo credit to
provide you with the location of their original source within
internet cyberspace. Those images may have separate
copyright protection. If you are seeking permission for use
of those images, you need to consult the original sources
for such permission; they are NOT mine to give you
permission.
Blood movement within the four-chambered heart of vertebrates
return from body
…to lung
semilunar valve
tricuspid valve
…from lung
semilunar valve
mitral valve
Note: arteries take blood away from the heart…veins return to heart
The difference is NOT about whether the blood is oxygenated or not!
©1996 Norton Presentation Maker, W. W. Norton & Company
…to body
2
Atria contract: ventricles filled,
valves close
©1996 Norton Presentation Maker, W. W. Norton & Company
Heart relaxes: atria filled by
1 system pressure
3
LUB
DUB!!
Ventricles contract: blood
sent to lungs and body
4
Heart relaxes: system
pressure closes valves
atrial contraction
“LUB”
and Purkinje fibers
ventricular
contraction
©1996 Norton Presentation Maker, W. W. Norton & Company
initial instrinsic
stimulus from
“pacemaker”
“DUB”
Frog Lab Exercise: neural and intrinsic control
The sounds are the slamming of valves…contraction is silent!
ventricular
depolarization
ventricular
release
atrial
depolarization
ventricle
relaxation
ventricle
filling
In abnormal heart behavior, this recording may reveal
where trouble spots exist within the heart’s electrical
controls.
Blood Pressure (mm Hg)
Electrical Potential (mV)
An electrocardiogram (EKG): the electrical changes
recorded from electrodes attached to the skin reveal the
electrical activity of the heart.
See Fig 45.25 pg 922
Comparative structure of blood vessels
High Pressure
Exchange
Low Pressure
Which of these has the greatest surface
to volume ratio?
©1996 Norton Presentation Maker, W. W. Norton & Company
See Fig 45.20 pg 918
smooth muscle
no valves
vein
less smooth muscle
valves significant
©1996 Norton Presentation Maker, W. W. Norton & Company
artery
©1996 Norton Presentation Maker, W. W. Norton & Company
Veins in valves: “check valves” prevent back flow during
heart cycles:
Pressure Pulse
Pressure Subsides
Valves prevent backflow
abnormal valve
during atrial contraction
“varicose veins”
blood flow
no flow
thrombus
©1996 Norton Presentation Maker, W. W. Norton & Company
Blood clotting (thrombosis) in a veinule
A thrombus that breaks free and moves through the rest of
the circulation system is called a thromboembolus and can
lodge in other areas of the body resulting in pulmonary (lung)
embolism, stroke (brain), or myocardial (heart) infarction.
Atheroschloersis: “hardening of the arteries”
Normal artiole
Arteriole
occluded with
fatty plaque
plaque
Blood flow will be restricted,
oxygenation will be
reduced.
Even a small group of cells
could completely cut off the
flow (myocardial infarction).
©1996 Norton Presentation Maker, W. W. Norton & Company
Blood pressure varies with distance from heart
aorta
BP is usually
arteries
measured in
systolic
pressure the radial artery
arterioles
100
40
20
veinules
60
diastolic
pressure
When a
sphygmomanometer
gives a result of
120/80 mm Hg, it is
interpreted as close
to normal for men.
capillaries
Blood pressure (mm Hg)
120
80
See Fig 45.27 pg 923
veins
vena cava
0
Distance traveled by blood from left ventricle
Vena cava
Veins
Arterioles
Capillaries
Venules
Arteries
50-
-5,000
40-
-4,000
30-
-3,000
20-
-2,000
10-
-1,000
Cross-sectional Area (cm2)
Velocity (cm/sec)
Aorta
Flow rate in blood vessels in a circulation system
Distance travelled by blood from left ventricle
Branching explains why you don’t get the “thumb on the hose nozzle” effect
Human capillaries are only wide
enough for one RBC to pass
©1996 Norton Presentation Maker, W. W. Norton & Company
Frog foot webbing capillaries
come close to each body cell
©1996 Norton Presentation Maker, W. W. Norton & Company
Capillary walls are a single endothelial cell joined at edges
pinocytosis (vesicular transport) brings
materials through capillary wall
©1996 Norton Presentation Maker, W. W. Norton & Company
Red Blood Cells (erythrocytes) and White Blood Cells
Figure 44.11 page 985
Figure 44.15 page 989
Oxygen is bound to hemoglobin at the chelation site of iron (Fe)
in heme:
H3C
C
HC
H3C
C
H2C
C
COOH
C
CH
C
C
N
C
N
CH2
CH2
HC
O=O
Fe
C
C
N
C
C
C
C
CH2 CH3
CH2
CH3
C
CH
N
C
HC
C
CH
CH2
notice the
resonating
bond
system to
help trap
the oxygen
molecule
in large
electron
cloud
COOH
Iron is a macroelement for vertebrates!
Gas exchanges at the blood-tissue interface
CO2
tissue cell cytosol
CO2
CO2 + H2O
O2
HCO3- + H+
capillary plasma
red blood cell
CO2 + H2O
HCO3- + H+
H+ + HbO2
CO2 + HbO2
HbCO2 + O2
HHb + O2
circulation direction
CO2
CO2
HbO2
CO2
HbO2
H2O
HbO2
H2O
H2O
HbO2
lungs HCO - H+
3
O2
HHb
HCO3O2
O2
CO2
HHb
HCO3-
HbO2
H+ HCO
3
-
tissues
HHb
HCO3O2
O2
Percent saturation of Hb with O2
Dissociation curves for hemoglobin explain oxygen exchange
100
Unloading to
tissues at
normal pH
circulation
80
60
Normal
blood
pH
40
20
Exercise Rest
0
0
Lungs
20
40
60
80 100 120
Oxygen partial pressure (mm Hg)
Percent saturation of Hb with O2
Dissociation curves for hemoglobin explain oxygen exchange
100
Unloading to
tissues at
normal pH
circulation
80
60
Normal
blood
pH
40
Oxygen unloaded at
low pH (high CO2)
Low
blood pH
20
Exercise Rest
0
0
Lungs
20
40
60
80 100 120
Oxygen partial pressure (mm Hg)
Percent saturation of Hb with O2
A placental mammal fetus has fetal hemoglobin with higher
affinity for oxygen than the mother’s hemoglobin in the
placenta
100 Unloading to
fetal tissues
80
transfer of oxygen
from maternal to
fetal hemoglobin in
the placenta
60
40
20
0
Fetus
Mother
0
20
40
60
80 100
Oxygen partial pressure (mm Hg)
Myoglobin in tissues has higher oxygen affinity than hemoglobin
Human and Maternal/Fetal circulation
capillary bed
artery
or
vein?
artery or
vein?
©1996 Norton Presentation Maker, W. W. Norton & Company
artery
or vein?
shunts
away from
lungs
artery
or
vein?
arterioles
veinules
artery
capillary bed
Note: What kind of circulation is shown in placenta?
The mammal body tissues possess myoglobin, which has an
even higher affinity for oxygen:
Percent saturation of Hb with O2
See Fig 45.17 pg. 915
Unloading to fetal
tissue myoglobin
100
80
transfer of oxygen
from maternal to
fetal hemoglobin in
the placenta
60
Fetus
40
20
0
Mother
0
20
40
60
80
100
Oxygen partial pressure (mm Hg)
Myoglobin in tissues has higher oxygen affinity than hemoglobin
gas exchange
muscular pump
glucose control
nitrogenous waste
gas exchange
nutrient exchange
blood cell
replacement
absorbing nutrients
©1996 Norton Presentation Maker, W. W. Norton & Company
Circulation system in mammal (Homo sapiens)