Cardiovascular System: Chapter 18 Flashcards
What carries blood away from the heart; Oxygenated except for pulmonary circulation
Arteries
What contacts tissue cells and directly serve cellular needs?
Capillaries
What carries blood toward heart
Veins
What are the central blood containing spaces in the blood vessel walls?
Lumen
What are the three wall layers in arteries and veins?
Tunica Intima, Tunica Media, Tunica Externa
What is the layer that is endothelium that lines the lumen of all vessels; continuous with endocardium and has a slick surface which reduces friction?
Tunica Intima
What is the layer that has smooth muscle and sheets of elastin; controls vasoconstriction and vasodilation; INFLUENCE BLOOD FLOW AND BP
Tunica Media
What is the layer that protects and reinforce; anchors to surrounding structures; nourishes external layer
Tunica Externa
Blood vessels vary in Length, Diameter, wall thickness, and tissue make-up. T/F
True
What type of artery is large, thick-walled; Elastin is all 3 tunics, large lumen and offers low resistance; NOT active in vasoconstriction; Expands and recoil as blood ejected from heart
Elastic Arteries
Where are elastic arteries found?
Aorta and major branches
What type of artery is distal to the elastic arteries; Deliver blood to body organs, think tunica media with more smooth muscle; IS active in vasoconstriction
Muscular Arteries
What are the smallest arteries; leads to capillary beds; control flow into capillary beds via Vasodilation and Vasoconstriction
Arterioles
Which artery is larger in diameter?
Elastic Artery
What are considered to be microscopic vessels; found in the walls of thin tunica intima; diameter allows only a single RBC to pass through
Capillaries
Provide direct access for almost every cell; Exchange of gases,nutrients,wastes,hormones, etc between blood and interstitial fluid; Found in all tissues except cartilage, epithelial, cornea, and lens of the eye
Capillaries
What are the three types of capillaries?
Continuous Capillaries, Fenestrated Capillaries, Sinusoid Capillaries
What is the LEAST permeable and most common capillary; abundant in skin and muscle?
Continuous Capillaries
What capillary is more permeable than continuous, its function is absorption or filtrate formation; (Ex:Small Intestines, Endocrine glands,Kidneys) “Baby-Swiss Cheese”
Fenestrated Capillaries
What capillary is super leaky, “MOST permeable”;Found in liver,bone marrow,spleen,adrenal medullar
Sinusoid Capillaries
What are networks of capillaries interwoven between arterioles and venules?
Microcirculation
What connects terminal arteriole and postcapillary venule?
Vascular Shunt
10-100 exchange vessels per capillary bed; branch off metarteriole or terminal arteriole?
True Capillaries
T/F: True capillaries normally branch from metarteriole and return to thoroughfare channel.
TRUE
What regulates blood flow into the true capillaries?
Precapillary Sphincters
T/F: Blood may go into true capillaries or to the vascular shunt; which are regulated by local chemical conditions and vasomotor nerves?
TRUE
What is formed when capillary beds unite?
Venules
What is formed when venules converge?
Veins
Have thinner walls,LARGER lumens, blood pressure is lower than in arteries, thin tunica media and thick tunica externa
Veins
What holds most of the bodies blood? Heart, capillaries, pulmonary blood vessels, or veins?
Systemic Veins and venules
What are vascular anastamoses?
interconnection of blood vessels
What type of anastamoses provides alternate pathways to given body region? Found at joints,abdominal organs, brain and heart
Arterial Anastamoses
What is an example of an arteriovenous anastomoses?
Vascular shunts of capillaries
What is the force per unit area exerted on wall of blood vessel by blood?
Blood Pressure
What are three important sources of resistance?
blood viscosity(thickness), total blood vessel length, blood vessel diameter
