Unit 1 Lecture 1 Flashcards
What are the 3 components of the cardiovascular system?
- Heart
- Blood
- Blood vessels
What does the heart do?
Acts as a pump to propel blood
What does blood do?
Moves through tubes called blood vessels
What do blood vessels do?
Conducts blood throughout the body
What is the heart called?
double pump
What is important about circulation of blood?
Circulation is CONTINUOUS
How many trips does blood travel through the heart?
2 CONTINUOUS trips
What is a “circuit”
each “stop” for blood at the heart
What is the path of blood through the heart?
heart -> arteries -> capillaries -> veins -> heart
What are the 2 cardiovascular circuits?
- Systemic circuit
- Pulmonary circuit
What does systemic circuit do?
Carries oxygen & nutrients through blood to the cells of our body
What does the pulmonary circuit do?
reloads blood with oxygen
What are the 4 chambers within the heart?
- Left and right atrium
- Left and right ventricle
Blood enters the heart through what chamber?
Atrium
Blood exists the heart through what chamber?
Ventricle
What does the systemic circuit do?
carries oxygenated blood (arterial blood) to body cells/tissues/organs
What is the path of the systemic circuit?
Begins w/ LEFT VENTRICLE of art (ejects blood in the aorta) and ends w/ the RIGHT ATRIUM (collects returning blood)
How does the systemic circuit distribute blood?
in PARALLEL manner
What are major recipients of blood?
Kidneys, GI system, skeletal muscle, brain, skin, heart
also liver, bone
What does the pulmonary circulation do?
carries de-oxygenated blood (“venous blood”) to the lungs, RELOADS with OXYGEN, and empties with CO2
What is the path of the pulmonary circuit?
Begins w/ RIGHT VENTRICLE (ejects blood into the pulmonary trunk) and ends w/ LEFT atrium (collects returning blood)
Fluids move against what?
Pressure gradients
Pressure is higher in what?
Arteries (not veins)- thicker wall can resist pressure
What is cardiac output
the value for the amount of fluid that moves through the heart at a given time
- pumped by ventricle
- same for both systemic & pulmonary circuits
What is the value of cardiac output?
5 L/min
What happens if cardiac output is too much?
Heart could burst
What happens if cardiac output is too low?
Cell dies
What is the heart made up of?
Cardiac muscle
What is the path of blood through the whole body?
Right atrium (deoxy) -> right ventricle -> pulmonary trunk -> lungs (oxy) Left atrium -> left ventricle -> aorta -> body -> right atrium
The atria do what?
Receive blood
The ventricles do what?
force blood out of heart and into circuits
Which ventricle is thicker and has more muscle?
Left bc it has a greater workload
How many heart valves are there?
4
What are the different valves?
- Left and right atrioventricular valves
- left and right semilunar valve
What is the left atrioventricular (AV) valve called?
Bicupsid valve or “mitral” valve
What is the right AV valve called?
tricuspid valve
What does the mitral valve separate?
left atrium and left ventricle
What does the tricuspid valve separate?
right atrium and right ventricle
What do AV valves have inside of them?
Chordae tendinae
What is chordae tendinae?
stringy tendons connected to the valve cusps and the inner ventricle walls
What does chordae tendinae prevent?
Prevents the “prolapse” of the valves into the atria during ventricular contraction
What is the name of the muscles in the AV valves?
papillary muscles
What do papillary muscles do?
regulate tension in the chordae tendinae and contract simultaneously with the ventricles
What is the name of the two semilunar valves?
aortic semilunar and pulmonary semilunar valves
What does the aortic semilunar valve separate?
separates the left ventricular chamber from the aorta
What does the pulmonary semilunar valve separate?
right ventricular chamber from the pulmonary trunk
How do BOTH AV and Semilunar valves open?
in pressure- dependent manners
What does it mean when something opens in pressure dependent manners?
They open and close in response to pressure differences between the major vessels and the heart ventricles
aortic pressure > ventricular pressure =?
closed valve
aortic pressure < ventricular pressure =?
open valve
AV and semilunar valves do what together?
open and close
what is coronary circulation?
The part of systemic circulation that provides the heart tissue with blood
what ensures blood is delivered to heart tissue even if vessels are blocked?
anastomoses (or collateral routes)
How does the tissue of the heart get blood?
from the right and left coronary arteries
Where do the right and left coronary arteries originate?
the ascending aorta
What does the right coronary artery supply?
SA node, AV node, parts of the right atrium, in interventricular septum, and both ventricles
What are the 2 branches of the right coronary artery?
marginal and posterior interventricular branch
What does the marginal branch supply?
Anterior portions of the right ventricle
What does the posterior interventricular branch supply?
posterior portions of both ventricles
What does the left coronary artery supply?
SA node, parts of the left atrium, the interventricular septum, and both ventricles
What are the two branches of the left coronary artery?
Circumflex and anterior interventricular branch
What does the circumflex branch supply?
left atrium and posterior regions of the left ventricle
What does the anterior interventricular branch supply?
anterior portions of both ventricles
What are the 2 veins of the heart?
great cardiac vein and middle cardiac vein
what does the great cardiac vein do?
drains the anterior heart
What does the middle cardiac vein do?
drains the posterior heart
Where do BOTH veins drain into?
the coronary sinus
where does the coronary sinus drain into?
right atrium
