Blood Vessels and Circulation Flashcards
transport blood from the
right ventricle, through the lungs, and back to the left atrium
Pulmonary vessels
transport blood from the left ventricle, through all parts of the body, and back to the right atrium
Systemic vessels
The circulatory system has five unique functions:
Carries blood
Exchange nutrients, waste products, and gases with tissues
Transport substances
Helps regulate blood pressure
Direct blood flow to tissues
Scattered along the length of the capillary are ________________ closely associated with the endothelial cells.
Pericapillary cells
Most capillaries range from ____________ in diameter, and they branch without changing in diameter.
7 μm to 9 μm
three main types of blood vessels are:
Arteries
Capillaries
Veins
All blood vessels have an internal lining of simple squamous epithelial cells called the
Endothelium
Capillaries are classified as
Continuous
Fenestrated
Siinusoidal
are larger in diameter than either continuous or fenestrated capillaries, and their basement membrane is less prominent
Sinusoidal capillaries
are similar in structure to the sinusoidal capillaries but even larger in diameter.
Venous sinuses
They are found primarily in the spleen, and there are large gaps between the
endothelial cells that make up their walls.
venous sinuses
Blood flows from arterioles to capillary networks through
Metarterioles
Blood then flows from a metarteriole into a
Thoroughfare channel
are specialized vascular connections that allow blood to flow directly from arterioles to small veins without passing through capillaries.
Arteriovenous anastomoses
is an arteriovenous anastomosis that consists of arterioles with abundant smooth muscle in their walls.
Glomus
can form in areas of the body as a result of injury or tumors.
Pathologic arteriovenous anastomoses
The tunica intima consists of four layers:
endothelium
a basement membrane
a thin layer of connective tissue called the lamina propria
a fenestrated layer of elastic fibers called
the internal elastic membrane
separates the tunica intima from the tunica media
internal elastic membrane
or middle layer, consists of smooth muscle cells arranged circularly around the blood vessel.
Tunica media
separates the tunica media from the tunica
adventitia.
External elastic membrane
have the largest diameters and are often called conducting arteries.
Elastic arteries
include medium-sized and small arteries
Muscular arteries
are the smallest veins.
Venules
As the vessels increase to 0.2–0.3 mm in
diameter, the smooth muscle cells form a continuous layer; the vessels are then called
Small veins
Most of the veins observed in gross anatomical dissections are
Medium veins
Large veins
transport blood from the medium veins to the heart
Large veins
In some areas of the body, a capillary network is directly connected to another capillary network by
Portal veins
Veins that have diameters greater than 2 mm contain
Valves
which allow blood to flow toward the heart, but not in the opposite direction
valves
which penetrate from the exterior of the vessel to form a capillary network in
the tunica adventitia and the tunica media
Vasa vasorum
(hardening of the arteries) consists of degenerative changes in arteries that make
them less elastic.
Arteriosclerosis
is the deposition of material in the walls of arteries to form distinct plaques.
Atherosclerosis
The heart pumps deoxygenated blood from the right ventricle into a short artery (about 5 cm long) called the
Pulmonary trunk
All arteries of the systemic circulation are derived either directly or indirectly from the
Aorta
Three general parts of aorta
Ascending aorta
Aortic arch
Descending aorta
Ascending aorta is approximately 5 cm
long and has only two arteries branching from it:
Right coronary arteries
Left coronary arteries
The aorta then arches posteriorly and to the left as the
Aortic arch
Three major arteries branch from the aortic arch and carry blood to the head and upper limbs.
Brachiocephalic artery
Left common carotid artery
Left subclavian artery
is the longest part of the aorta and it extends
through the thorax in the left side of the mediastinum and through
the abdomen to the superior margin of the pelvis.
Descending aorta
which are the only branches of the ascending aorta
Coronary arteries
The first vessel to branch from the aortic arch is the
Brachiocephalic artery
The second branch of the aortic arch is the ___________________, which transports blood to the left side of the head and neck.
Left common carotid artery
The third branch of the aortic arch is the ____________, which transports blood to the left upper limb.
Left subclavian artery
each common carotid artery branches into
Internal carotid arteries
external carotid arteries
is a sudden neurological disorder, often caused by decreased blood supply to a part of the brain.
Stroke
The left and right vertebral arteries unite to form
Midline basilar artery
The left and right vertebral arteries
branches to form the ________________, which supply
the posterior part of the cerebrum
Posterior cerebral arteries
The middle cerebral arteries connect to the posterior cerebral arteries by way of the
Posterior communicating arteries
The three major arteries of the upper limb are the
Subclavian
Axillary
Brachial arteries
is formed by the ulnar artery and is completed by anastomosing with the radial artery.
Superficial palmar arch
is formed by the radial artery and is completed by anastomosing with the ulnar artery.
Deep palmar arch
The branches of the thoracic aorta are divided into two groups:
Visceral branches
parietal branches
supplying portions of the thoracic
organs
Visceral branches
supplying portions of the thoracic wall
Parietal branches
The thoracic walls are supplied with blood by the
Intercostal arteries
which consist of two sets: the anterior intercostals and the posterior intercostals.
Intercostal arteries
supply blood to the diaphragm.
Superior phrenic arteries
There are three major unpaired
branches of the abdominal aorta:
Celiac trunk
Superior mesenteric artery
Inferior mesenteric artery
At the level of the fifth lumbar vertebra, the abdominal aorta divides into
Two common iliac arteries
