CH 20 HW Flashcards
By definition, arteries are blood vessels that do what?
Carry blood away from the heart
The endothelium is made of which type of epithelial tissue?
Simple squamous, super flat cells
Name of the small blood vessels that nourish the walls of larger vessels?
Vasa vasorum
What term refers to a weak, bulging point in the wall of a heart chamber or blood vessel?
Aneurysm
What is the order of the tunics from innermost to outermost?
Tunica interna, tunica media, and tunica external (adventitia)
What makes up the capillary wall?
Basal Lamina and Endothelium
What are the functions of the endothelium?
Acts as a selectively permeable barrier to materials entering or leaving the bloodstream, secretes chemicals that stimulate dilation or constriction of the vessel, and repels RBCs and platelets to retain flow
Where are continuous capillaries found?
Most tissues like skeletal muscle
Where are fenestrated capillaries found?
Organs that engage in rapid absorption or filtration of small molecules like the small intestine and kidneys
Where are sinusoids found?
Areas where large proteins and cells need to enter or leave the bloodstream like the liver and spleen
The vasa vasorum are small vessels that supply blood to which of the following?
The walls of large blood vessels. They provide nutrients to the wall of large blood vessels because the blood moves through the vessel too quickly for the vessel to absorb nutrients from it
Newly formed blood cells enter circulation from the bone marrow and lymphatic organs by passing through the walls of what?
Sinusoids
Blood flow into capillary beds is regulated by smooth muscle structures called what?
Precapillary Sphincters , they surround the openings to the capillaries
A weak, bulging sac in the wall of an artery that pulsates with each beat of the heart and which may eventually rupture is called?
An aneurysm
Is the diameter of some capillaries smaller than the diameter of an RBC?
Yes, RBCs get squished and change shape to fit into these tiny capillaries
A circulatory route in which blood flows through two consecutive capillary networks before returning to the heart
A portal system
Put capillary types in order from least permeable to most permeable
Continuous capillaries, fenestrated capillaries, and Sinusoids
T or F: The femur has greater blood flow but less perfusion than the ovary
True! Perfusion is the ratio of flow to grams of tissue
Name for the irregular blood-filled spaces in the liver, bone marrow, spleen, and some other organs?
Sinusoids
The force that the blood exerts against a vessel wall?
Blood pressure
Blood flow into capillary beds is regulated by ?
Precapillary Sphincters
Systolic pressure is the lowest where?
In veins closest to the heart
Valves that direct blood towards the heart are formed by unfolding of which layer of the vein wall?
The tunica interna
3 Factors that affect peripheral resistance
Vessel radius, blood viscosity, vessel length
3 places portal systems occur
The kidneys, between the hypothalamus anterior pituitary, and between the intestines and liver
The flow of blood per given volume or mass of tissue is known as…
Perfusion