Download Blood Vessels

The Cardiovascular
System: Blood Vessels
and Circulation
The Structure of Blood Vessels
Blood Vessel Review
• Arteries carry blood away from the heart
• Pulmonary trunk to lungs
• Aorta to everything else
• Microcirculation is where exchange occurs
• Arterioles to feed the capillaries
• Capillaries exchange with the tissues
• Venules to receive capillary blood
• Veins bring it back to the heart
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
The Structure of Blood Vessels
A Comparison of a Typical Artery and a
Typical Vein
Figure 13-1
The Structure of Blood Vessels
Arteries and Veins Have Three Layers
• Tunica interna
• Innermost layer (endothelium) in contact
with blood
• Tunica media
• Middle layer of smooth muscle
• Vasoconstrict or vasodilate
• Tunica externa
• Outer layer of loose connective tissue
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
The Structure of Blood Vessels
X Types of Arteries
• Elastic arteries
• Largest
• Closest to heart
• Stretch during systole
• Recoil during diastole
• Muscular arteries
• Arterioles
• Tiny branches of small arteries
• Feeders of capillary networks
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
The Structure of Blood Vessels
X The Structure
of the Various
Types of Blood
Vessels
Figure 13-2
The Structure of Blood Vessels
Properties of Capillaries
• Where exchange between blood
and cells takes place
• Organized into interconnected
capillary beds
• Precapillary sphincters (bands of
smooth muscle) controls flow
The Structure of Blood Vessels
The
Organization of
a Capillary Bed
Figure 13-4(a)
The Structure of Blood Vessels
The
Organization of
a Capillary Bed
Figure 13-4(b)
The Structure of Blood Vessels
Properties of Veins
• Collect blood from capillaries
• Merge into medium-sized veins
• Merge then into large veins
• Blood pressure is low here
• Valves keep blood flowing
toward the heart
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
The Structure of Blood Vessels
The Function of
Valves in the Venous
System
Figure 13-5
Circulatory Physiology
Factors Affecting Blood Flow
• Pressure
• Flow goes up as pressure difference
goes up
• Flow goes from higher to lower
pressure
• Regulated by nervous and endocrine
systems
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Circulatory Physiology
Factors Affecting Blood Flow
• Peripheral resistance
• Flow goes down as resistance
goes up
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Circulatory Physiology
Control of Peripheral Resistance
• Consists of three components:
• Vascular resistance
• Goes up as diameter is reduced
• Arteriole diameter dominates
• Viscosity of blood
• Depends on hematocrit
• Turbulence
• Cause of pathological sounds
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Circulatory Physiology
Pressures in the Systemic Circuit
• Arterial pressure
• Overcomes peripheral resistance to
maintain flow to the organs
• Capillary pressure
• Excessive pressure causes edema
• Venous pressure
• Low pressure that drives venous return
• Affects cardiac output and peripheral flow
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Circulatory Physiology
Arterial Pressure
• Rises during ventricular systole
• Falls during ventricular diastole
• Pulse pressure is difference between
systolic pressure and diastolic pressure
• Lessens with distance from heart
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Circulatory Physiology
Pressures Within the Circulatory System
Figure 13-6
Circulatory Physiology
Checking the
Pulse and Blood
Pressure
Figure 13-8(a)
Circulatory Physiology
Checking the Pulse and Blood Pressure
Figure 13-8(b)
Circulatory Physiology
Functions of Capillary Exchange
• Maintain communication between
plasma and interstitial fluid
• Speed the distribution of nutrients,
hormones, and dissolved gases
• Flush antigens to lymphoid tissue
• Aid movement of proteins
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Circulatory Physiology
Dynamics of Capillary Exchange
• Small molecules diffuse across
endothelium
• Water follows osmotically
• Balance of forces determines
direction of filtration
• Capillary pressure forces fluid out
• Protein osmotic pressure pulls fluid in
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Circulatory Physiology
Forces Acting Across Capillary Walls
Figure 13-7
Circulatory Physiology
Factors Assisting Venous Return
• Low venous resistance
• Valves in veins
• Compression of veins by muscular
contraction
• Respiratory pump pulls blood into
thorax
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Circulatory Physiology
Key Note
Blood flow is the goal. Total peripheral
blood flow is equal to cardiac output.
Blood pressure is needed to overcome
friction to sustain blood flow. If blood
pressure is too low, vessels collapse,
blood flow stops, and tissues die; if too
high, vessel walls stiffen and capillary
beds may rupture.
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Cardiovascular Regulation
Factors Affecting Tissue Blood Flow
• Cardiac output
• Peripheral resistance
• Blood pressure
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Cardiovascular Regulation
Homeostasis of Tissue Perfusion
• Autoregulation
• Local control of pre-capillary sphincters
• CNS control
• Responds to blood pressure, blood gases
• Hormone control
• Short-term adjustments
• Blood pressure
• Peripheral resistance
• Long-term adjustments
• Blood volume
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Cardiovascular Regulation
Local, Neural, and Endocrine Adjustments
That Maintain Blood Pressure and Blood Flow
Figure 13-9
Cardiovascular Regulation
Neural Control of Blood Flow and
Pressure
• Baroreceptor reflexes
• Adjust cardiac output and peripheral
resistance to maintain normal blood
pressure
• Driven by baroreceptors
• Aortic sinus
• Carotid sinus
• Atrial baroreceptors
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Cardiovascular Regulation
Neural Control of Blood Flow and
Pressure
• Chemoreceptor reflexes
• Respond to changes in CO2, O2 and pH
• Sense blood and cerebrospinal fluid
• Impact cardioacceleratory, cardioinhibitory
and vasomotor centers
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Blood pressure
reduced
Blood pressure
elevated
HOMEOSTASIS
RESTORED
Decreased
cardiac
output
HOMEOSTASIS
RESTORED
HOMEOSTASIS
Vasodilation
occurs
Vasomotor
centers inhibited
Cardioinhibitory
centers stimulated
Cardioacceleratory
centers inhibited
Normal range
of blood
pressure
HOMEOSTASIS
HOMEOSTASIS
DISTURBED
DISTURBED
Blood pressure
Blood pressure
rises above
falls below
normal range
normal range
REFLEX
RESPONSE
Baroreceptors
inhibited
REFLEX
RESPONSE
Baroreceptors
stimulated
Inhibition
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Vasoconstriction
occurs
Increased
cardiac output
Vasomotor
centers stimulated
Cardioinhibitory
centers inhibited
Cardioacceleratory
centers stimulated
Figure 13-10
1 of 12
HOMEOSTASIS
Normal range
of blood
pressure
HOMEOSTASIS
DISTURBED
Blood pressure
rises above
normal range
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 13-10
2 of 12
HOMEOSTASIS
Normal range
of blood
pressure
HOMEOSTASIS
DISTURBED
Blood pressure
rises above
normal range
Cardioinhibitory
centers stimulated
Cardioacceleratory
centers inhibited
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
REFLEX
RESPONSE
Baroreceptors
stimulated
Inhibition
Figure 13-10
3 of 12
HOMEOSTASIS
Normal range
of blood
pressure
HOMEOSTASIS
DISTURBED
Blood pressure
rises above
normal range
Decreased
cardiac
output
Cardioinhibitory
centers stimulated
Cardioacceleratory
centers inhibited
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
REFLEX
RESPONSE
Baroreceptors
stimulated
Inhibition
Figure 13-10
4 of 12
Decreased
cardiac
output
Vasodilation
occurs
HOMEOSTASIS
Normal range
of blood
pressure
HOMEOSTASIS
DISTURBED
Blood pressure
rises above
normal range
Vasomotor
centers inhibited
Cardioinhibitory
centers stimulated
Cardioacceleratory
centers inhibited
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
REFLEX
RESPONSE
Baroreceptors
stimulated
Inhibition
Figure 13-10
5 of 12
Blood pressure
reduced
HOMEOSTASIS
RESTORED
Decreased
cardiac
output
Vasodilation
occurs
HOMEOSTASIS
Normal range
of blood
pressure
HOMEOSTASIS
DISTURBED
Blood pressure
rises above
normal range
Vasomotor
centers inhibited
Cardioinhibitory
centers stimulated
Cardioacceleratory
centers inhibited
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
REFLEX
RESPONSE
Baroreceptors
stimulated
Inhibition
Figure 13-10
6 of 12
HOMEOSTASIS
Normal range
of blood
pressure
HOMEOSTASIS
DISTURBED
Blood pressure
falls below
normal range
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 13-10
7 of 12
HOMEOSTASIS
Normal range
of blood
pressure
HOMEOSTASIS
DISTURBED
Blood pressure
falls below
normal range
REFLEX
RESPONSE
Baroreceptors
inhibited
Inhibition
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Cardioinhibitory
centers inhibited
Cardioacceleratory
centers stimulated
Figure 13-10
8 of 12
HOMEOSTASIS
Normal range
of blood
pressure
HOMEOSTASIS
DISTURBED
Blood pressure
falls below
normal range
REFLEX
RESPONSE
Baroreceptors
inhibited
Inhibition
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Increased
cardiac output
Cardioinhibitory
centers inhibited
Cardioacceleratory
centers stimulated
Figure 13-10
9 of 12
HOMEOSTASIS
Normal range
of blood
pressure
HOMEOSTASIS
DISTURBED
Blood pressure
falls below
normal range
REFLEX
RESPONSE
Baroreceptors
inhibited
Vasoconstriction
occurs
Increased
cardiac output
Vasomotor
centers stimulated
Inhibition
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Cardioinhibitory
centers inhibited
Cardioacceleratory
centers stimulated
Figure 13-10
10 of 12
Blood pressure
elevated
HOMEOSTASIS
RESTORED
HOMEOSTASIS
Normal range
of blood
pressure
HOMEOSTASIS
DISTURBED
Blood pressure
falls below
normal range
REFLEX
RESPONSE
Baroreceptors
inhibited
Vasoconstriction
occurs
Increased
cardiac output
Vasomotor
centers stimulated
Inhibition
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Cardioinhibitory
centers inhibited
Cardioacceleratory
centers stimulated
Figure 13-10
11 of 12
Blood pressure
reduced
Blood pressure
elevated
HOMEOSTASIS
RESTORED
Decreased
cardiac
output
HOMEOSTASIS
RESTORED
HOMEOSTASIS
Vasodilation
occurs
Vasomotor
centers inhibited
Cardioinhibitory
centers stimulated
Cardioacceleratory
centers inhibited
Normal range
of blood
pressure
HOMEOSTASIS
HOMEOSTASIS
DISTURBED
DISTURBED
Blood pressure
Blood pressure
rises above
falls below
normal range
normal range
REFLEX
RESPONSE
Baroreceptors
inhibited
REFLEX
RESPONSE
Baroreceptors
stimulated
Inhibition
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Vasoconstriction
occurs
Increased
cardiac output
Vasomotor
centers stimulated
Cardioinhibitory
centers inhibited
Cardioacceleratory
centers stimulated
Figure 13-10
12 of 12
Respiratory
centers
stimulated
Respiratory
rate increases
Cardioacceleratory
centers stimulated
REFLEX
RESPONSE
Chemoreceptors
stimulated
Increased cardiac
output and
blood pressure
Cardioinhibitory
centers inhibited
Vasomotor
centers
stimulated
Increased pH and
O2 levels,
decreased CO2
levels in blood
Vasoconstriction
occurs
HOMEOSTASIS
RESTORED
HOMEOSTASIS
DISTURBED
Decreased pH and
O2 levels, elevated CO2
levels in blood and CSF
HOMEOSTASIS
Normal pH, O2,
and CO2 levels
in blood and
CSF
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Inhibition
Figure 13-11
1 of 6
HOMEOSTASIS
DISTURBED
Decreased pH and
O2 levels, elevated CO2
levels in blood and CSF
HOMEOSTASIS
Normal pH, O2,
and CO2 levels
in blood and
CSF
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 13-11
2 of 6
Cardioacceleratory
centers stimulated
REFLEX
RESPONSE
Chemoreceptors
stimulated
HOMEOSTASIS
DISTURBED
Decreased pH and
O2 levels, elevated CO2
levels in blood and CSF
Cardioinhibitory
centers inhibited
HOMEOSTASIS
Normal pH, O2,
and CO2 levels
in blood and
CSF
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Inhibition
Figure 13-11
3 of 6
Cardioacceleratory
centers stimulated
REFLEX
RESPONSE
Chemoreceptors
stimulated
Cardioinhibitory
centers inhibited
Vasomotor
centers
stimulated
HOMEOSTASIS
DISTURBED
Decreased pH and
O2 levels, elevated CO2
levels in blood and CSF
Increased cardiac
output and
blood pressure
Vasoconstriction
occurs
HOMEOSTASIS
Normal pH, O2,
and CO2 levels
in blood and
CSF
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Inhibition
Figure 13-11
4 of 6
Respiratory
centers
stimulated
Respiratory
rate increases
Cardioacceleratory
centers stimulated
REFLEX
RESPONSE
Chemoreceptors
stimulated
Cardioinhibitory
centers inhibited
Vasomotor
centers
stimulated
HOMEOSTASIS
DISTURBED
Decreased pH and
O2 levels, elevated CO2
levels in blood and CSF
Increased cardiac
output and
blood pressure
Vasoconstriction
occurs
HOMEOSTASIS
Normal pH, O2,
and CO2 levels
in blood and
CSF
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Inhibition
Figure 13-11
5 of 6
Respiratory
centers
stimulated
Respiratory
rate increases
Cardioacceleratory
centers stimulated
REFLEX
RESPONSE
Chemoreceptors
stimulated
Increased cardiac
output and
blood pressure
Cardioinhibitory
centers inhibited
Vasomotor
centers
stimulated
Increased pH and
O2 levels,
decreased CO2
levels in blood
Vasoconstriction
occurs
HOMEOSTASIS
RESTORED
HOMEOSTASIS
DISTURBED
Decreased pH and
O2 levels, elevated CO2
levels in blood and CSF
HOMEOSTASIS
Normal pH, O2,
and CO2 levels
in blood and
CSF
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Inhibition
Figure 13-11
6 of 6
Cardiovascular Regulation
The Hormonal
Regulation of Blood
Pressure and
Blood Volume
Figure 13-12(a)
Cardiovascular Regulation
The Hormonal
Regulation of Blood
Pressure and
Blood Volume
Figure 13-12(b)
Cardiovascular Regulation
X Hormonal CV Regulation
• Short-term regulation
• Epinephrine from adrenal medulla
• Cardiac output and peripheral
resistance
• Long-term regulation
• Antidiuretic Hormone (ADH)
• Angiotensin II
• Erythropoietin (EPO)
• Atrial natriuretic peptide (ANP)
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Cardiovascular Regulation
X Hormone Effects on CV Regulation
• ADH, angiotensin II promote
vasoconstriction
• ADH, aldosterone promote water, salt
retention
• EPO stimulates RBC production
• ANP promotes sodium, water loss
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Cardiovascular Regulation
Key Note
Cardiac output cannot be increased
indefinitely, and so blood flow to
active tissues must be increased and
flow to inactive tissue reduced. A
combination of autoregulation, neural
regulation, and hormone release
accomplish this.
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Patterns of CV Response
Exercise and the Cardiovascular System
•
•
•
•
Cardiac output rises
Blood flow to skeletal muscle increases
Flow to non-essential organs falls
Exercise produces long-term benefits
• Larger stroke volumes
• Slower resting heart rates
• Greater cardiac reserves
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Patterns of CV Response
X Response to Hemorrhage (Blood
Loss)
•
•
•
•
Increase in cardiac output
Mobilization of venous reserves
Peripheral vasoconstriction
Release of hormones that defend
blood volume
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
The Blood Vessels
Vessels of the Pulmonary Circuit
• Pulmonary trunk
• From right ventricle to lungs
• Pulmonary arteries (left and right)
• Pulmonary veins (left and right)
• To left atrium
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
The Blood Vessels
An Overview of the
Pattern of Circulation
Figure 13-13
The Blood Vessels
The Pulmonary Circuit
Figure 13-14
The Blood Vessels
The Systemic Circulation
• Ascending aorta
• From left ventricle
• Feeds coronary circulation
• Aortic arch
• Feeds shoulders, neck, head
• Descending aorta
• Feeds inferior body regions
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
The Blood Vessels
An Overview of
the Arterial
System
Figure 13-15
The Blood Vessels
Arteries of the
Chest and
Upper Limb
Figure 13-16
The Blood Vessels
A Flow Chart Showing the Arterial Distribution
to the Head, Chest, and Upper Limbs
Figure 13-17
The Blood Vessels
Arteries of the
Neck, Head,
and Brain
Figure 13-18
The Blood Vessels
Major Arteries of
the Trunk
Figure 13-19(a)
The Blood Vessels
Major Arteries of
the Trunk
Figure 13-19(b)
The Blood Vessels
X Anatomy of Arterial Supply
Contrasts
with Venous Drainage
• Major arteries in neck and limbs
all lie deep
• Major veins form a dual-venous
drainage
• Are either superficial or deep
• Serves temperature control needs
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
The Blood Vessels
Anatomy of Venous Drainage
• Superior vena cava
• Drains head, neck, shoulders, arms, chest
• Inferior vena cava
• Drains most of body below diaphragm
• Hepatic portal vein
• Carries blood draining the digestive system
to the liver for purification and storage of
absorbed nutrients
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
The Blood Vessels
An Overview of
the Venous
System
Figure 13-20
The Blood Vessels
Major Veins of the Head and Neck
Figure 13-21
The Blood Vessels
The Venous
Drainage of
the Abdomen
and Chest
Figure 13-22
The Blood Vessels
A Flow Chart of the Circulation to the
Superior and Inferior Venae Cavae
Figure 13-23(a)
The Blood Vessels
A Flow Chart
of the
Circulation to
the Superior
and Inferior
Venae Cavae
Figure 13-23(b)
The Blood Vessels
The Hepatic Portal System
Figure 13-24
The Blood Vessels
Fetal Circulation
• Placenta
• Receives two umbilical arteries from
fetus
• Drained by one umbilical vein to the
fetus
• Joins ductus venosus in liver
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
The Blood Vessels
Fetal Circulation
• Pulmonary bypass
• Lets blood flow skip the lungs
• Foramen ovale
• Between atria in interatrial septum
• Becomes fossa ovalis in adult
• Ductus arteriosus
• Between pulmonary trunk and aorta
• Both pathways close after birth
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
The Blood Vessels
Fetal Circulation
Figure 13-25(a)
The Blood Vessels
Fetal Circulation
Figure 13-25(b)
Aging and the CV System
Age Related Changes in the Blood
• Decreased hematocrit
• Vessel blockage by a thrombus
(blood clot)
• Pooling in the legs resulting from
faulty valves
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Aging and the CV System
Age Related Changes in the Heart
•
•
•
•
Reduction in maximal cardiac output
Impaired nodal and conduction function
Stiffening of cardiac skeleton
Retricted coronary flow due to
atherosclerosis
• Fibrous replacement of damaged
myocardium
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Aging and the CV System
Age Related Changes in Blood Vessels
• Embrittlement of arterial walls by
arteriosclerosis
• Increased risk of aneurism
• Calcium deposits in lumen
• Increased risk of thrombus
• Thrombus formation at atherosclerotic
plaques
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
The Cardiovascular System
in Perspective
FIGURE 13-26
Functional Relationships Between
the Cardiovascular System and Other Systems
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 13-26
1 of 11
The Integumentary System
• Stimulation of mast cells
produces localized changes in
blood flow and capillary
permeability
• Delivers immune system cells to
injury sites; clotting response
seals breaks in skin surface;
carries away toxins from sites of
infection; provides heat
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 13-26
2 of 11
The Skeletal System
• Provides calcium needed for
normal cardiac muscle
contraction; protects blood
cells developing in bone
marrow
• Provides calcium and
phosphate for bone deposition;
delivers EPO to bone marrow,
parathyroid hormone, and
calcitonin to osteoblasts and
osteoclasts
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 13-26
3 of 11
The Muscular System
• Skeletal muscle contractions
assist in moving blood
through veins; protects
superficial blood vessels,
especially in neck and limbs
• Delivers oxygen and
nutrients, removes carbon
dioxide, lactic acid, and heat
during skeletal muscle activity
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 13-26
4 of 11
The Nervous System
• Controls patterns of
circulation in peripheral
tissues; modifies heart rate
and regulates blood pressure;
releases ADH
• Endothelial cells maintain
blood-brain barrier; help
generate CSF
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 13-26
5 of 11
The Endocrine System
• Erythropoietin regulates
production of RBCs; several
hormones elevate blood
pressure; epinephrine
stimulates cardiac muscle,
elevating heart rate and
contractile force
• Distributes hormones
throughout the body; heart
secretes ANP
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 13-26
6 of 11
The Lymphatic System
• Defends against pathogens or
toxins in blood; fights infections of
cardiovascular organs; returns
tissue fluid to circulation
• Distributes WBCs; carries
antibodies that attack pathogens;
clotting response assists in
restricting spread of pathogens;
granulocytes and lymphocytes
produced in bone marrow
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 13-26
7 of 11
The Respiratory System
• Provides oxygen to
cardiovascular organs and
removes carbon dioxide
• RBCs transport oxygen and
carbon dioxide between lungs
and peripheral tissues
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 13-26
8 of 11
The Digestive System
• Provides nutrients to
cardiovascular organs;
absorbs water and ions
essential to maintenance of
normal blood volume
• Distributes digestive tract
hormones; carries nutrients,
water, and ions away from
sites of absorption; delivers
nutrients and toxins to liver
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 13-26
9 of 11
The Urinary System
• Releases renin to elevate
blood pressure and
erythropoietin to accelerate
red blood cell production
• Delivers blood to capillaries,
where filtration occurs;
accepts fluids and solutes
reabsorbed during urine
production
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 13-26
10 of 11
The Reproductive System
• Sex hormones maintain
healthy vessels, estrogen
slows development of
atherosclerosis
• Distributes reproductive
hormones; provides
nutrients, oxygen, and waste
removal for developing fetus;
local blood pressure
changes responsible for
physical changes during
sexual arousal
Copyright © 2007 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 13-26
11 of 11