Blood Vessels Flashcards
what is the function of blood vessels?
- Transport blood to tissues and back to heart
- regulate blood flow to tissues
- control blood pressure
- secrete a variety of chemicals
what are the two circuits that carries blood through the body?
Pulmonary circuit
Systemic circuit
transport blood between the heart and the lungs
Pulmonary circuit
transport blood between the heart and the rest of the body
Systemic circuit
what are the three kinds of blood vessels in the pulmonary and systemic circuits?
Arteries, capillaries, and veins
(Distribution system) as they travel away from the heart they branch off into smaller vessels that supply most tissues in the body with blood
Arteries
(Exchange system) small vessels that form branching networks called capillaries. gases, nutrients, wastes, and other molecules are quickly
exchanged between tissue cells and blood
through capillary walls
Capillaries
(Collection system) drain
blood from capillary beds and return it to heart
Veins
what is the central space of the blood vessel called?
Lumen
Name the three tunics (layers) of blood vessels?
Tunica intima
Tunica media
Tunic externa
a type of artery that conduct blood under high pressure to blood vessels
Elastic arteries
a type of artery that control blood flow to organs and regulate blood pressure
Muscular arteries
a type of artery that control blood flow to tissues and feed capillary beds
Arterioles
a vein that drain capillary beds
Venules
this disease is characterized by formation of atherosclerotic plaques; buildups of lipids, cholesterol, calcium salts, and cellular debris within arterial tunica intima
Atherosclerosis
locations where vessels connect via pathways called collateral vessels
Vascular Anastomoses
A type of anastomoses that can be formed when blood flow through an artery is insufficient to meet tissue’s metabolic needs
Arterial Anastomoses
most common type of anastomosis;
neighboring veins are connected by small collaterals; smaller veins are often so interconnected that they form complex, weblike patterns
Venous anastomosis
a type of anastomosis where artery empties directly into a vein without passing through a capillary bed
Arteriovenous Anastomosis
physiology of blood flow in cardiovascular system
Hemodynamics
outward force that blood exerts on walls of blood vessels
Blood pressure
volume of blood that flows per minute
Blood flow
product of stroke volume
amount of blood pumped with each beat) times heart rate (number of beats per minute
Cardiac Output
average pressure in systemic arteries during an entire cardiac cycle; generally measures about 95 mm Hg
Mean arterial pressure (MAP)
*the amount of friction blood encounters during flow through blood vessels
Peripheral resistance
Which blood vessel tunic is innervated by nerves from the sympathetic nervous system?
tunica media
The closure of a precapillary sphincter prevents blood flow to tissues from
arterioles
Which vessels serve as the blood reservoirs of the body?
veins
Calculate the mean arterial pressure (MAP) if the systolic pressure is 120 mm Hg and the diastolic pressure is 90 mm Hg.
100 mm Hg
Which of the following does NOT drive venous return?
a) skeletal muscle pump
b) smooth muscle in the walls of veins
c) low compliance
d) venous valves
c) low compliance
During exercise, cardiac output may increase by more than 170% to meet the body’s increased O2 demands. This increase in cardiac output increases blood pressure. But the accompanying increase in arterial pressure is relatively small—only about 40%. What limits this increase in blood pressure so that it doesn’t reach dangerously high levels during exercise?
Vasodilation causes arterial diameter to increase in the exercising skeletal muscle.
Blood pressure would INCREASE as a result of a DECREASE in __________.
blood vessel diameter
Which of the following changes would produce the greatest change in total peripheral resistance?
a) 10% change in vessel diameter
b) 10% change in blood viscosity
c) 10% change in vessel length
d) 10% change in cardiac output
a)10% change in vessel diameter
Which of the following is a cause of hypertension?
a) renal artery stenosis
b) excess parasympathetic tone
c) dehydration
d) decreased salt intake
a)renal artery stenosis
Where are the sensors for the arterial baroreceptor reflex located?
carotid sinus and aortic arch
If blood pressure is increased at the arterial baroreceptors, what would happen with the activity level of the parasympathetic nervous system (PNS) and sympathetic nervous system (SNS)?
increased PNS activity and decreased SNS activity
Which of the following would cause vasodilation of arterioles?
a) increased activity of the sympathetic nervous system
b) decreased activity of the parasympathetic nervous system
c) decreased activity of the sympathetic nervous system
d) increased activity of the parasympathetic nervous system
c)decreased activity of the sympathetic nervous system
Stimulation of the adrenal medulla would result in which of the following?
a) a decrease in cardiac output
b) vasodilation of arteries
c) an increase in heart rate and contractility
d) a decrease in blood pressure
c) an increase in heart rate and contractility
A decrease in blood pressure at the arterial baroreceptors would result in which of the following?
a) a decrease in heart rate
b) a decrease in cardiac output
c) an increase in heart contractility
d) vasodilation of arterioles
c)an increase in heart contractility
Hypertension is defined as:
high blood pressure
Which of the following stimuli is detected by a chemoreceptor?
a) stretch in the walls of arteries
b) increased blood pressure
c) decreased blood oxygen concentration
d) vasodilation of arterioles
c)decreased blood oxygen concentration
Which vessels vasoconstrict in response to epinephrine and norepinephrine?
systemic arterioles
Which of the following is NOT an effect of the hormone Angiotensin II?
a) increased thirst
b) triggers the secretion of Aldosterone
c) vasoconstriction
d) decreased cardiac output
d) decreased cardiac output
