Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
87 Cards in this Set
- Front
- Back
Components of the cardiovascular system
|
A closed system of the heart (pumps blood) and blood vessels (allow blood to circulate)
|
|
Functions of the cardiovascular system
|
To deliver oxygen and nutrients to cells and tissues
To remove carbon dioxide and other waste products from cells and tissues |
|
Closed cardiovascular system
|
Blood stays only inside the heart and blood vessels
|
|
Orientation of the heart
|
Pointed apex directed toward left hip, base points toward right shoulder
|
|
Pericardium
|
A double walled sac around the heart, functions as protection, low-friction, attaches heart to diaphragm, serous fluid fills the space inbetween the layers
|
|
Fibrous pericardium
|
Loose and superficial
|
|
Serous membrane
|
Deep to the fibrous pericardium and composed of two layers
|
|
Visceral pericardium
|
Next to heart, also known as the epicardium
|
|
Parietal pericardium
|
Outside layer that lines the inner surface of the fibrous pericardium
|
|
Three layers of the heart wall
|
Epicardium, Myocardium, Endocardium
|
|
Epicardium
|
The visceral pericardium, the outside connective tissue layer
|
|
Myocardium
|
Middle layer, "skeleton of the heart", mostly cardiac muscle, transmits APs
|
|
Endocardium
|
Inner layer, continuous with the epithelium of blood vessels
|
|
Atria
|
Receiving chambers where blood enters the heart, located at the superior of the heart, composed of right and left atrium
|
|
Ventricles
|
Discharging chambers that contract to push blood up and out of the heart, located at the inferior of the heart, composed of right and left ventricle
|
|
Septa
|
Prevents blood from mixing between the right and left pump
|
|
Interventricular septum
|
Separates the two ventricles
|
|
Interatrial septum
|
Separates the two atria
|
|
Systematic Circulation
|
Blood flows from the left side of the heart through the body tissues and back to the right side of the heart
|
|
Pulmonary Circulation
|
Blood flows from the right side of the heart to the lungs and back to the left side of the heart
|
|
Function of valves
|
Allow blood to flow in only one direction to prevent backflow
|
|
Atrioventricular valves (AV)
|
Between atria and ventricles, bicuspid valve and tricuspid valve, anchored in place by chordae tendinea. They open during heart relaxation and close during ventricular contraction which prevents blood from backwards into atria
|
|
Semilunar valves
|
Between ventricle and artery. Pulmonary and Aortic semilunar valves. Closed during heart relaxation but open during ventricle contraction to prevent blood from falling back to ventricles
|
|
Arteries
|
Blood vessels that are taking away from the heart
|
|
Aorta
|
Artery that leaves the left ventricle
|
|
Pulmonary artery
|
Leave the right ventricle, the pulmonary trunk splits into the right and left pulmonary arteries
|
|
Veins
|
Blood vessels carrying blood back to the heart
|
|
Superior vena cava
|
Enters right atrium, drains blood from top of body to the heart
|
|
Inferior vena cava
|
Enters right atrium, drains blood from bottom of body
|
|
Pulmonary veins
|
Enter left atrium, carries blood from the lungs to the heart
|
|
Coronary arteries
|
Branch from the aorta to supply the heart muscle with oxygenated blood
|
|
Cardiac veins
|
Drain the myocardium of blood
|
|
Coronary sinus
|
A large vein on the posterior of the heart, receives blood from cardiac veins
|
|
Cardiac Circulation
|
Blood in the heart chambers does not nourish the myocardium, the heart has its own nourishing circulatory system (coronary arteries, cardiac veins, coronary sinuses). Blood empties into the right atrium via the coronary sinus
|
|
Intristic conduction system
|
Heart muscle cells contract without action potentials in a regular continuous way
|
|
Sinoatrial Node
|
SA node, the "pacemaker" of the heart. Found in the wall of the right atrium
|
|
Atrioventricular node
|
AV node, Is found at the junction of the atria and ventricles
|
|
Atrioventricular bundle
|
Is in the interventricular septum
|
|
Heart block
|
Damage to the intristic conduction system usually SA or AV node damage. Ventricles generate poor rhythm by themselves
|
|
Ishemia
|
Lack of adequate oxygen supply to heart muscle
|
|
Fibrillation
|
A rapid, uncoordinated shuddering of the heart muscle (heart failure)
|
|
Defibrillator
|
Outside electric shock to reset the normal rhythm of the heart
|
|
Tachycardia
|
Rapid heart rate
|
|
Bradycardia
|
Slow heart rate
|
|
Systole
|
A contraction of the ventricles
|
|
Diastole
|
Relaxation of the ventricles
|
|
How do atria contract?
|
simultaneously
|
|
Cardiac output
|
Amount of blood pumped by either side (ventricle) of the heart in one minute
|
|
Stroke volume
|
Volume of blood pumped by each ventricle in one heart beat, this usually remains constant. About 70ml of blood is pumped out of the left ventricle with each heart beat
|
|
Heart rate
|
Typically 75 beats per minute
|
|
Cardiac output formula
|
Heart rate x stroke volume
|
|
Starling's law of the heart
|
The more the cardiac muscle is stretched, the stronger the contraction
|
|
What is the most common way to change cardiac output?
|
Changing the heart rate
|
|
Increased heart rate is regulated by what?
|
The sympathetic nervous system, during a fight or flight response
|
|
Hormones that regulate the heart rate
|
Epinepherine and Thyroxine
|
|
Decreased heart rate is controlled by what?
|
Parasympathetic nervous system
|
|
Role of arteries and arterioles
|
Carry blood away from the heart
|
|
Arterioles
|
Smaller branches off of main arteries
|
|
Capillary bed's function
|
Location of exchanges between tissues and blood
|
|
Function of veins and venules
|
Return blood towards the heart
|
|
Venules
|
Small veins that form larger veins
|
|
Is blood always oxygenated?
|
No, not in pulmonary arteries
|
|
Three layers of a blood vessel
|
Tunica intima, tunica media, tunica externa
|
|
Tunica intima
|
Endothelium, very thin and smooth tissue
|
|
Tunica media
|
Smooth muscle controlled by the sympathetic nervous system, allows blood vessels to change in diameter
|
|
Tunica externa
|
Mostly fibrous connective tissue, serves as a protective layer
|
|
Artery structural composition
|
Arteries have thick tunica media to deal with the blood pressure they endure. Often change diameter with vasoconstriction or dilation depending on the demand for blood in a certain area.
|
|
Capillary structural composition
|
Only one cell layer thick (tunica intima) to allow for exchanges between blood and tissues
|
|
Vein structural composition
|
Has a thinner tunica media then arteries, they contain valves to prevent backflow of blood.
Lumen in veins are larger then arteries. Large lumen and stretchy walls act as blood reservoirs. Veins have relatively thin walls. They have very low blood pressure |
|
Lumen
|
Space inside a blood vessel
|
|
Blood flow in arteries
|
Due to ventricular contraction, blood is forced through arteries and arterioles
|
|
Blood flow in veins
|
Veins have very low blood pressure, Blood flow is basically slowed to a stop. Blood gets back to the heart because of the "muscular pump" and "respiratory pump".
Basically: Contraction of skeletal muscles squeezes veins, pushes blood upwards (bc valves don't allow downwards movement) back to the heart |
|
Capillary beds consist of which types of vessels?
|
Vascular shunt and True capillaries
|
|
Vascular Shunt
|
Vessel through a capillary bed connecting an arteriole to a venule
|
|
True capillaries
|
These are exchange vessels. Oxygen and nutrients cross to cells, and carbon dioxide and metabolic waste products cross into blood
|
|
Individual capillary characteristics
|
The diameter is so small blood cells move through one at a time, blood moves very slowly
|
|
Precapillary sphincters
|
Rings of smooth muscle, if relaxed blood goes into capillaries, if constricted blood stays in vascular shunt
|
|
Pulse
|
Pressure wave of blood in arteries, averages 70-76 beats per minute
|
|
Blood pressure
|
Measurements by health professionals are made on the pressure in large arteries
|
|
Systolic blood pressure
|
pressure at the peak of ventricular contraction
|
|
Diastolic blood pressure
|
pressure when ventricles relax
|
|
Peripheral resistance
|
Amount of friction blood encounters as it flows through vessels
|
|
How do kidneys regulate blood pressure?
|
The kidneys sense blood pressure is low and release renin which causes the release of aldosterone which retains water and sodium in blood to increase blood pressure
|
|
Effect of temperature on blood
|
Heat has a vasodilating effect on blood vessels, cold has a vasoconstricting effect on blood vessels
|
|
Hypotension
|
Low systolic blood pressure, associated with illness
|
|
Hypertension
|
High systolic blood pressure, very dangerous if chronic, very genetic
|
|
Intristic conduction system
|
Allows the heart to beat on its own
|