Cardiovascular System
Chapter 13
Objectives:
1. Identify structures and functions
of the cardiovascular system.
2. Trace the flow of blood through
the body.
Coverings of the Heart
• Pericardium: (?)
1. Visceral (?)pericardium (“epicardium”(?))
– Innermost layer
– Covers the heart
2. Parietal (?)pericardium
– Outer layer of visceral pericardium
– Forms inner lining of fibrous pericardium
3. Fibrous (?)pericardium
– Dense connective tissue attached to central
portion of diaphragm, posterior of sternum,
vertebral column, and large blood vessels
attached to heart
Pericardial Cavity
• Space between parietal and visceral
pericardium layers
• Filled with serous fluid to reduce friction
between the membranes as the heart
moves
Wall of the Heart
1. Epicardium
–
–
–
Outer layer
Corresponds to visceral pericardium
Protects heart by reducing friction
2. Myocardium
–
–
Thick, middle layer
Consists mostly of cardiac muscle tissue that
pumps blood out of the heart chambers
3. Endocardium
–
–
Inner layer
Epithelium and connective tissue
Heart Chambers & Valves
• ????
• Four hollow chambers:
– Upper chambers = atria (atrium)
– Lower chambers = ventricles
• Atria
– Thin walls
– Receive blood returning to the heart
• Ventricles
– Receive blood from the atria
– Contract to force blood out of the heart into
the arteries
Heart Chambers & Valves,
continued…..
• Left atrium and ventricle are separated
from the right atrium and ventricle by a
solid, wall-like septum.
• Atrioventricular valves – separate ???
1. Tricuspid valve
•
•
on the right
“3 cusps”
2. Bicuspid valve (“mitral valve”)
•
•
on the left
“2 cusps”
– Allows blood to flow ONLY from atrium to
ventricular – no backflow
Heart Chambers & Valves,
continued…..
• Right atrium receives blood from:
– Superior vena cava (???)
– Inferior vena cava (???)
– Coronary sinus – small vein that drains blood
from the myocardium
• Right ventricle
– Thinner muscular wall than the left ventricle
– Only has to pump blood to the lungs
• Blood leaves the ventricle through the
pulmonary valve, and enters the pulmonary
trunk, which divides into the left and right
pulmonary arteries.
Heart Chambers & Valves,
continued…..
• Left atrium receives blood from the lungs
through 4 pulmonary veins.
• Blood leaves the left ventricle through the
aortic valve, into the aorta.
• Ventricular wall is thicker than that of the
right ventricle – has to pump blood to the
rest of the body
Sketch & Label the Valves
Label the Exterior Heart
Label the Interior Heart
Add to Your Labeled Diagrams
1. Color the areas that contain oxygenated
blood red.
2. Color the areas that contain
unoxygenated blood blue. (***WHAT
COLOR IS UNOXYGENATED BLOOD,
REALLY?)
3. Add arrows to indicate the direction of
blood through the whole system.
4. Write in the areas each blood vessel is
going to or coming from (i.e., lungs,
body, heart muscle).
Blood Supply to the Heart
• Coronary arteries
– Supply oxygenated blood to the heart muscle
– The first 2 branches off the aorta, right beside
the aortic valve
– These are tiny!
• Cardiac veins
– Return blood from the myocardium to the
coronary sinus.
– What is the coronary sinus?
Blood Vessels
• Arteries → arterioles → capillaries →
venules → veins → ???
• Gas exchange between the blood and
body tissues occurs in which blood
vessels?
• Arteries are under relative high pressure.
• Veins have valves that prevent a backflow
of blood.
Paths of Circulation
• Two major pathways:
1. Pulmonary circuit - lungs
2. Systemic circuit – body and heart
• BOTH pathways have the 5 types of blood
vessels.
• The pulmonary circuit starts when blood
is pumped out of the __________, and
ends when blood returns to the _______.
• The systemic circuit starts when blood is
pumped out of the __________, and ends
when blood returns to the _______.
•
Arterial System
• Aorta
– Largest diameter artery
– Exits the left ventricle (1. ascending aorta)
– Curves over the top and to the left of the heart
(2. aortic arch)
– 3. Descending aorta gradually moves
medially(?) until it lies directly in front of the
vertebral column
• Descending aorta ABOVE the diaphragm: 4. thoracic
aorta
• BELOW the diaphragm: 5. abdominal aorta
For this next part, you will need:
1. Handout to label as we go.
2. Add this chart to your notes *****:
Portion of Aorta
Major Branches
General Regions or
Organs Supplied
Major Arteries of the Ascending Aorta
• Right and left coronary arteries
Major Arteries of the Aortic Arch
1. Brachiocephalic artery
2. Left common carotid artery
3. Left subclavian artery
Major Arteries of the Descending Aorta
•
Bronchial artery
Major Arteries of the Thoracic Aorta
1.
2.
3.
4.
Pericardial artery
Esophageal artery
Mediastinal artery
Posterior intercostal artery
Major Arteries of the Abdominal Aorta
1. Celiac artery ( gives rise to gastric,
splenic, and hepatic arteries)
2. Phrenic artery
3. Superior mesenteric artery
4. Suprarenal arteries
5. Renal arteries
6. Gonadal arteries
7. Inferior mesenteric artery
8. Lumbar arteries
9. Middle sacral artery
10.Common iliac arteries
Arteries to the Neck, Head, and Brain
• These branch off the subclavian and
common carotid arteries.
1. Vertebral arteries
– branch off the subclavian arteries
– pass through the transverse foramina of the
cervical vertebrae
– Enter the skull through the foramen magnum
– Supply blood to the vertebrae and their
ligaments and muscles
Arteries to the Neck, Head, and Brain,
continued…..
2. Thyrocervical arteries
– short vessels that branch off the subclavian
arteries
– give off branches to the thyroid gland,
parathyroid glands, larynx, trachea,
esophagus, and pharynx
Arteries to the Neck, Head, and Brain,
continued…..
3. Left and right common carotid arteries
diverge into internal and external carotid
arteries
– External carotid artery goes up the side of the
head giving off branches to structures in the
neck, face, jaw, and base of the skull
– Internal carotid artery follows a deeper course
along the pharynx to the base of the skull
• Provides the major blood supply to the brain
Arteries to the Shoulder and Upper
Limb
• After the subclavian artery pass between
the clavicle and the 1st rib, it becomes the
axillary artery, which then becomes the
brachial artery.
• A deep brachial artery branches off the
brachial artery and curves around the
humerus to supply the triceps brachii.
• At the elbow, the brachial artery branches
into radial and ulnar arteries. They rejoin
at the wrist.
• Which artery is used for taking a pulse?
Arteries to the Pelvis and Lower Limb
• Common iliac arteries divide into internal
and external arteries.
– Internal supplies pelvic muscles and organs
– External supplies lower limbs – becomes the
femoral artery
• Femoral artery supplies muscles and
tissues of the thigh area.
• As it approaches the knee, it becomes the
popliteal artery, supplying the knee joint
and muscles in the thigh and calf.
Arteries to the Pelvis and Lower Limb,
continued…..
• Popliteal artery branches into:
– Anterior tibial artery
– Posterior tibial artery
• Anterior tibial artery:
– Passes between tibia and fibula
– Supplies skin and muscles in anterior and
lateral parts of leg
– Becomes the dorsalis pedis artery (???)
• Posterior tibial artery:
– Descends beneath the calf muscle
– Supplies skin, muscles, and other tissues of
the leg
Venous System
• MOST veins follow closely along their
same-named arteries. (example: brachial
artery and brachial vein)
• Notable differences:
– Aorta vs. vena cava
– Internal and external carotid arteries vs.
internal and external jugular veins