Chapter 11: Circulatory System Flashcards
includes both the blood and lymphatic vascular system; pumps and directs blood cells and substances carried in blood to all tissues of the body
circulatory system
the ____ propels blood through the system and is surrounded by the ________, a fibrous sac lined by serous mesothelium
heart; pericardium
a series of vessels efferent from the heart that become smaller as they branch into the various organs, carry blood to the tissues
arteries
the smallest vessels, are the sites of O2, CO2, nutrient, and waste product exchange between blood and tissues
capillaries
capillaries form a complex network of thin tubules called the _____
microvasculature or microvascular bed
the convergence of venules into a system of larger channels which continue enlarging as they approach the heart
veins
the internal surface of all components of the blood and lymphatic systems is lined by a ____ ____ epithelium called __________
simple squamous; endothelium
heart chamber that pumps blood to the lungs
right ventricle
heart chamber that pumps blood to the body
left ventricle
heart chamber that receives blood from the body
right atria
heart chamber that receives blood from the lungs
left atria
heart layer that contains single layer of endothelial cells, thin layer of fibroelastic CT, and Purkinje fibers
Endocardium
heart layer that is thicker around ventricles than the atria; thickest part of the heart; contains cardiac muscle
Myocardium
heart layer that contains simple squamous mesothelium, layer of loose CT with blood vessels and nerves, and secretes serous fluid (lubrication)
Epicardium or Visceral Pericardium
prominent dense irregular CT comprising the fibrous cardiac _____ separates the musculature of the atria from that of the ventricles
skeleton
heart valves inner region are lined by ______
endothelial
in both the subendocardial and myocardium layers, modified cardiac muscle cells make up the impulse _____ system of the heart
conducting
specialized to generate and conduct waves of depolarization, which stimulate rhythmic contractions in myocardial fibers
impulse conducting system
the impulse conducting system has two nodes of specialized myocardial tissue in the ____ ____ wall
right atrial
name of two nodes
sinoatrial (SA) and atrioventricular (AV) nodes
located in the right atrial wall; small mass of modified cardiac muscle calls with fewer myofibrils; generates and distributes electrical signals; pacemaker
sinoatrial (SA) node
located in the floor of the right atrium; small mass of modified cardiac muscle calls with fewer myofibrils; bundle of His; delayed response
atrioventricular (AV) node
pale-staining fibers; mingle distally with contractile muscle fibers of each ventricle and trigger waves of contraction through both ventricles simultaneously
Purkinje fibers
a blood glycoprotein involved in blood clotting; binds platelets
von Willebrands factor
At site of injury or infection, __-____ is expressed rapidly on the luminal surface when unique elongated granules, called ___-____ ____, fuse with the cell membrane
P-selectin; Weibel-Palade bodies
growth factors such as ______ _____ growth factor stimulate vasculogenesis and angiogenesis
vascular endothelial growth factor (VEGF)
formation of the vascular system from embryonic mesenchyme
vasculogenesis
capillary sprouting and outgrowth from small existing vessels
angiogenesis
___ ___ fibers occur in the walls of all vessels; connected by many gap junctions and permit vasoconstriction and vasodilation that help in regulating the overall blood pressure
smooth muscle
all larger vessels have walls with ____ concentric layers or tunics
three
the tunica _____ consists of the endothelium and a thin subendothelial layer of loose CT and sometimes containing smooth muscle fibers
tunica intima
In arteries, the intima includes a thin layer, the ____ ____ ___, composed of fenestrated elastin
internal elastic lamina
the tunica _____ consists chiefly of concentric layers of helically arranged smooth muscle cells
tunica media
In arteries, the media may also have an ____ ____ ___ separating it from the outermost tunic
external elastic lamina
the tunica ____ is CT consisting principally of type I collagen and elastic fibers
externa or adventitia
larger vessels usually have ____ ____ in the adventitia; required to provide metabolites to cells in those tunics in larger vessels because the wall is too thick to be nourished solely by diffusion from the blood in the lumen
vasa vasorum
have no tunics; endothelium cells rolled into a tube
capillaries
make up 90% of the body’s vasculature; slow blood flow (low pressure)
capillaries
_____ capillaries have many tight, occluding junctions between endothelial cells, which provide for continuity along the endothelium and well-regulated metabolic exchange across the cells
continuous
most common type of capillary found in muscle and CT
continuous
_____ capillaries have a sieve-like structure that allows more extensive molecular exchange across the endothelium
fenestrated
_____ capillaries are found in the kidneys and digestive system, like intestine
fenestrated
_____ capillaries, commonly called _____, permit maximal exchange of macromolecules
discontinuous; sinusoids
these capillaries are found in the liver, spleen, and bone marrow
discontinuous or sinusoids
secrete many ECM components and form their own basal lamina, which fuses w/ the basement membrane of the endothelial cells
pericytes
after injuries, ____ differentiate to form smooth muscle and other cells in new vessels as the microvasculature is reestablished
pericytes
contain an abundance of actin and myosin - contractile properties; regulate blood flow; blood-brain barrier
pericytes
