Lecture 18
Circulatory System I
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Blood
• Matrix between the
cells is liquid
• Hemopoiesis
– Process of formation of
blood cells
– Tissue found in
marrow cavity and
spongy bone
• Yellow
• Red
Table 4.13
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Blood Vessel Structure
• Arteries
– Elastic, muscular, arterioles, capillaries
• Capillaries
– Most of exchange between blood and interstitial
spaces (filled with interstitial fluid) occurs
across the walls
– Blood flows from capillaries to venous system
• Aneurysm
– Weak point in artery or wall of heart
– May rupture (hemorrhage)
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Systemic Circulation: Arteries
• Aorta
– From which all arteries are derived either
directly or indirectly
– Parts
• Ascending aorta, aortic arch, descending aorta
(thoracic and abdominal)
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Branches of the Ascending Aorta
Fig. 22.9
• Coronary arteries
– Supply the heart’s cardiac muscle with oxygen
and nutrients
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Branches of the Aortic Arch
Right common carotid artery
• First branch
– Brachiocephalic
trunk
– Right common
carotid and right
subclavian
• Second branch
Vertebral artery
Right subclavian artery
Brachiocephalic trunk
Left common
carotid artery
Left subclavian
artery
Aortic arch
Descending
thoracic aorta
Fig. 23.12
– Left common
carotid
• Third branch
– Left subclavian
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Review Question
An interruption in blood flow that resulted in less
blood reaching the right shoulder and right neck
(but not affecting the opposite side) could
indicate a partial blockage in the
(a) Right subclavian artery
(b) Brachiocephalic artery
(c) Right common carotid artery
(d) Ascending aorta
(e) Coronary arteries
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Branches of the Aortic Arch:
Head and Neck Arteries
• Branches of common
carotid arteries
– Internal carotid
arteries
– External carotid
arteries
• Branches of the
subclavian arteries
– Left and right
vertebral arteries
• Internal carotids and
vertebral arteries
supply brain
Internal carotid artery
External carotid artery
Common carotid artery
Vertebral artery
Brachiocephalic trunk
Subclavian artery
Fig. 23.10
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Branches of the Aortic Arch:
Arteries of Upper Limb and Shoulder
• Three major arteries
– Subclavian
– Axillary
– Brachial
• Subclavian is
posterior to clavicle
• Axillary is within
axillary region
(armpit)
• Brachial is within
brachium (arm)
Subclavian artery
Vertebral artery
Axillary artery
Brachial artery
Radial artery
Ulnar artery
Fig. 23.19
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Branches of the Descending Aorta:
Arteries of the Abdominal Aorta
Celiac trunk
Right renal artery
Descending abdominal
aorta
Inferior mesenteric artery
Left renal artery
Superior mesenteric artery
Common iliac artery
Left internal iliac artery
Left external iliac artery
Left femoral artery
Fig. 23.12
• Three major branches (in order from superior to inferior along
abdominal aorta)
– Celiac trunk
– Superior mesenteric artery
– Inferior mesenteric artery
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Branches of the Descending
Aorta: Pelvis and Lower Limb
Anterior view
• Abdominal aorta
divides into:
Posterior view
Common iliac artery
External iliac artery
– Common iliac arteries
Internal iliac artery
Femoral artery
• Common iliac arteries
divide into:
– External iliac arteries
– Internal iliac arteries
Popliteal artery
Anterior tibial artery
Posterior tibial artery
• Popliteal artery
• Anterior and posterior
tibial arteries
Fig. 23.20
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Points to Remember
• Arteries transport blood away from the
heart
• Branches of aorta supply heart, head and
neck, shoulder and upper limb, trunk,
abdomen, pelvis and lower limb
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Questions?
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