Download 6.2 The Transport System Readings 210-215 Pg 216, 2-4

6.2
The Transport System
Readings 210-215
Pg 216, 2-4
6.2.1
Draw and label a diagram of the heart showing the four
chambers, associated blood vessels, valves and the route of
blood through the heart.
• Right ventricle  lungs  left atrium 
left ventricle  body tissues  right
atrium 
• Heart valves dictate a one-way flow of blood through
the heart
• Blood begins its flow with the right ventricle pumping
blood to the lungs
• In the lungs, the blood loads O2 and unloads CO2
• Oxygen-rich blood from the lungs enters the heart at
the left atrium and is pumped to the body tissues
by the left ventricle
• Blood returns to the heart through the right atrium
Capillaries of
head and
forelimbs
Anterior
vena cava
Pulmonary
artery
Pulmonary
artery
Capillaries
of right lung
Pulmonary
vein
Right atrium
Right ventricle
Posterior
vena cava
Aorta
Capillaries
of left lung
Pulmonary
vein
Left atrium
Left ventricle
Aorta
Capillaries of
abdominal organs
and hind limbs
Pulmonary artery
Aorta
Anterior
vena cava
Pulmonary
artery
Right
atrium
Left
atrium
Pulmonary
veins
Pulmonary
veins
Semilunar
valve
Semilunar
valve
Atrioventricular
valve
Atrioventricular
valve
Posterior
vena cava
Right
ventricle
Left
ventricle
6.2.2
State that the coronary arteries supply heart
muscle with oxygen and nutrients.
6.2.3
Explain the action of the heart in terms of collecting
blood, pumping blood, and opening and closing of
valves.
• The heart contracts and relaxes in a rhythmic
cycle called the cardiac cycle
• The contraction, or pumping, phase is called
systole
• The relaxation, or filling, phase is called diastole
• The heart rate, also called the pulse, is the
number of beats per minute
• The cardiac output is the volume of blood
pumped into the systemic circulation per minute
6.2.4
Outline the control of the heartbeat in terms of
myogenic muscle contraction, the role of the
pacemaker, nerves, the medulla of the brain and
epinephrine (adrenaline).
• Myogenic?
– Muscle that stimulates itself inside the heart, independent
from the brain.
• The sinoatrial (SA) node, or pacemaker, sets the rate
and timing at which cardiac muscle cells contract
• The pacemaker is influenced by nerves, hormones,
body temperature, and exercise
• Impulses from the SA node travel to the
atrioventricular (AV) node
• Epinephrine?
– From the adrenal gland, where is the adrenal gland located?
• Above the kidneys
– Increases cardiac rate
Pacemaker
generates wave of
signals to contract.
SA node
(pacemaker)
Signals pass
to heart apex.
Signals are delayed
at AV node.
AV
node
Bundle
branches
ECG
Signals spread
throughout
ventricles.
Heart
apex
Purkinje
fibers
6.2.5
Explain the relationship between the structure and
function of arteries, capillaries and veins.
• The “infrastructure” of the circulatory
system is its network of blood vessels
• All blood vessels are built of similar tissues
• Arteries have thicker walls that
accommodate the high pressure of blood
pumped from the heart
• In the thinner-walled veins, blood flows
back to the heart mainly as a result of
muscle action
Artery
Vein
100 µm
Endothelium
Valve
Basement
membrane
Endothelium
Endothelium
Smooth
muscle
Capillary
Connective
tissue
Smooth
muscle
Connective
tissue
Vein
Artery
Arteriole
Venule
6.2.6
State that blood is composed of plasma,
erythrocytes, leucocytes (phagocytes and
lymphocytes) and platelets.
• Blood is a solid or liquid?
– connective tissue
• Blood plasma is about 90% water
• Suspended in blood plasma are two types of cells:
– Red blood cells (erythrocytes) transport oxygen, make
up the majority of cells in the system
– White blood cells (leukocytes) function in defense
• Phagocytes (phagocytosis)
• Lymphocytes fight off specific antigens
• Platelets, a third cellular element, are fragments of
cells that are involved in clotting
• A fun note!
– Erythrocytes, leukocytes, and platelets all develop from a
common source, stem cells in the red marrow of bones
Platelets
erythrocytes
Lymphocytes
leukocytes
Phagocytes
6.2.7
State that the following are transported by the
blood: nutrients, oxygen, carbon dioxide,
hormones, antibodies, urea and heat.
• All the items listed above are transported
by the blood in the circulatory system…but
• What item in blood transports the oxygen
and carbon dioxide?
– Red blood cells (erythrocytes)