cardiovascular system Flashcards
Arteries, arterioles and capillaries carry blood going ______ the heart
away from
venules and veins carry blood going _______ the heart
towards
What are the 3 layers that make up arterial walls? (from in to out)
- tunica interna
- tunica media
- tunica externa
What makes up the tunica externa?
connective tissues
What makes up the tunica media?
smooth muscle
What makes up the tunica interna?
- innermost endothelium
- basement membrane
- internal elastic lamina
What happens to arteries during ventricle contraction?
the pressure of blood rises, and they expand
What happens to arteries during ventricle relaxation?
the pressure of blood falls, and they recoil
What is Angiogenesis?
the formation of new blood vessels from venules
What is arteriovenous anastomoses?
when blood from the arterioles passes directly into the venules without going through the capillaries
What is vasoconstriction, and what does it do to the rate of blood flow?
the contraction of smooth muscle within the arteries; decreases blood flow
What is vasodilation, and what does it do to the rate of blood flow?
the relaxation of smooth muscle within the arteries; increases blood flow
What’s the difference between continuous and discontinuous capillaries?
- continuous capillaries have closely joins adjacent endothelial cells, and permit the passage of molecules between blood and interstitial fluid
- discontinuous capillaries have a great distance between adjacent endothelial cells, and prevent the passage of molecules (they also create cavities in their respective organ)
Continuous capillaries are found in…
- muscles
- lungs
- adipose tissues
- central nervous system (contribute to blood-brain barrier)
Fenestrated capillaries are found in…
- kidneys
- intestines
- endocrine glands
What are fenestrated capillaries?
capillaries that contain wide intercellular pore covered by mucoprotein, and restrict the passage of molecules
What are the 3 types of capillaries?
- continuous
- discontinuous
- fenestrated
Discontinuous capillaries are found in…
- bone marrow
- liver
- spleen
What are is the role of capillaries?
location of gas exchange
Veins _____ as they accumulate more blood
expand
What is the role of a venous valve?
to ensure one-way blood flow to the heart
What is the skeletal muscle pump?
- contraction of muscles help return blood to the heart
- essential in lower limbs
- increases during physical activity
What is the abdomen’s equivalent to muscles in the skeletal muscle pump?
the diagram
What are the 4 chambers in the heart?
- right atrium
- left atrium
- right ventricle
- left ventricle
What is the role of the atria?
receive blood from the venous system
What is the role of the ventricles?
pump blood into the arteriole system
the atria and ventricles are separated by the…
fibrous skeleton
Describe the steps of pulmonary circulation (with deoxygenated blood starting within the muscles)
- blood travels through the veins, and enters the superior/inferior vena cava, which brings it to the right atrium
- blood passes through the tricuspid valve, and is pumped into the right ventricle
- blood passes through the pulmonary valve, and is pumped into the pulmonary truck
- blood travels through the pulmonary arteries, and is re-oxygenated in the lungs
Describe the steps of systematic circulation (with oxygenated blood beginning in the lungs)
- the pulmonary vein transports the blood to the left atrium
- blood passes through the bicuspid/mitral valve, and is pumped into the left ventricle
- blood passes through the aortic valve, and is pumped into the aorta
- blood enters the arteries, and is pumped to the body
The _____ ventricle is ______ than the right ventricle because…..
left ventricle is thicker than the right because it has the work harder
What’s an Atrioventricular Valve (AV)? What is its function?
a valve embedded within the fibrous skeleton that prevents back flow of blood from the ventricle into the atrium
What are the 2 kinds of atrioventricular valves, and where are they located?
- tricuspid valve; between the right atrium and ventricle
- bicuspid valve; between the left atrium and ventricle.
How many flaps does the tricuspid valve have?
3
How many flaps does the bicuspid valve have?
2
What’s the role of a Semilunar Valve?
opens during ventricular contraction, and closes during relaxation to prevent back flow into the ventricles