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Cardiovasc System
Question | Answer |
---|---|
Small arteries | arterioles |
Small veins | Venules |
White blood cells typicall leave circulation to enter tissues at _____ | postcapillary venule |
______ are the smallest vessels. They consist of a single layer of _______ cells and their ________. | Capillaries, endothelial cells, basal lamina |
Specialized ______ fibers synchronize the contraction of the heart to make contractions more efficient. | cardiac muscle |
Electrical impulses are initiated at the ______ node, or the pacemaker | sinoatrial (SA) |
Impulses spread through the atria to the _______ node | atrioventricular (AV) |
The impulse is transmitted to the ventricles by the ______ | bundle of His |
Bundle of His divides into ____ and ____ bundle branches | right, left |
Further branching into subendothelial branches is known as ______ | Purkinje fibers |
Composed of endothelial cells, basal lamina and subendothelium connective tissue layer. | Tunica intima |
Composed of circumferentially arranged smooth muscle | Tunica media |
Outermost connective tissue layer, composed mostly of collagenous tissue and a few elastic fibers | Tunica adventitia |
Small blood vessels that nourish the tunica media are called ______. Is in this tunic layer in large vessels: _______ | vasa vasorum, tunica adventitia |
A network of autonomic nerves found in tunica adventitia that controls the contraction of smooth muscle | nervi vascularis |
Elastic arteries have multiple sheets of ____. They function primarily as _____. | elastic layers, conduction tubes |
Largest elastic arteries: | Aorta, Pulmonary artery, Main branches of aorta (brachiocephalic, common carotid, subclavian, common iliac arteries) |
In Tunica Intima layer, Weibel-Palade bodies contain _____ | von Willebrand factor (coagulating factor VII) |
Most von Willebrand factor is synthesized by __________. | arterial endothelial cells. |
Endothelial cells maintain nonthrombogenic barrier between platelets and sebendothelial tissue by producing ______ and ________ | anticoagulants (thrombomodulin), and antithrombogenic sustances (prostacyclin and tissue plasminogen activator) |
Damage to endothelial cells causes them to releast prothombogenic agents such as ________ and _______ | von Willebrand factor, plasminogen activator inhibitor |
Endothelial cells modulate blood flow and vascular resistance by secreting ______ and _____. | Vasoconstrictors (endothelin, angiotensin-converting enzyme, {ACE}), Vasodilators (endothelial-derived relaxation factor {EDRF/NO}, prostacyclin) |
Foam cells are derived from _____ and _____ | macrophages and smooth muscle |
Muscular arteries (also known as _____ arteries). It has more ____ and less ____ in the tunica media than elastic arteries. | medium artery, smooth muscle, elastin |
In muscular artery, the tunica media is composed almost entirely of ______ | smooth muscle |
Muscular arteries have a prominent ______ | internal elastic membrane |
Continuous capillaries are found in: ____, ____, and ____ | muscle, lung, and CNS |
______ junctions, a type of tight junctions, seal continuous capillaries together | occluding |
Relatively unspecialized cells derived from the same precursor cell that gives rise to endothelial cells | Pericytes |
Fenestrated capillaries are found in: _____, _____, and ______ | endocrine glands, intestinal tract, and gallbladder |
Discontinuous capillaries are found in: _____, _____, _____ | liver, spleen, and bone marrow |
Discontinuous capillaries are also called ______ or _____ | sinusoidal capillaries or sinusoids |
__________ of metarterioles control blood flow into the capillary bed | Precapillary sphincters |
Large veins have a thick tunica ______, and a thin tunica _____ | adventitia, media |
Venous channels in the cranial cavity are lined with _______ cells and are called ______ | endothelial, venous or dural sinuses |
The two largest lymph vessels are the ____ and ____ | thoracic duct, right lymphatic duct |