Module C Flashcards
what is the structure of the cardiovascular system?
Right atrium - Returns of blood form the venous circulations (venous return)
Right ventricle- Pumping of venous blood into the pulmonary circulation
Left atrium - Reservoir for blood coming, from pulmonary circulation, primes the left ventricle
Left ventricle - Pumping of (oxygenated) into the systemic circulation
what is the function of cardiovascular system (cardiac output) ?
(CO) is a measurement of the amount of blood pumped by each ventricle in one minute.
describe the cardiac action
The cardiac action potential is a brief change in voltage (membrane potential) across the cell membrane of heart cells.
This action potential passes along the cell membrane causing the cell to contract,
the structure of arteries
Each artery is a muscular tube lined by smooth tissue and has three layers:
1) The intima,
2) the inner layer lined by a smooth tissue called endothelium.
3) The media, a layer of muscle that lets arteries handle the high pressures from the heart.
the function of arteries
Arteries transport blood away from the heart.
- arteries Have thick muscular and elastic walls to pump and accommodate blood
the structure of veins
consists of three main layers.
- The outer layer is connective tissue, called tunica adventitia or tunica extern
- The middle layer of smooth muscle called the tunica media,
- The inner layer lined with endothelial cells called the tunica intima.
the function of veins
Veins return blood back toward the heart.
- veins Have thin walls - have less muscular tissue than arteries
the structure of capillaries
Capillaries are very thin, and are composed of only two layers of cells—an inner layer of endothelial cells and an outer layer of epithelial cells.
- They are so small that red blood cells need to flow through them single file.
the function of capillaries
Capillaries surround body cells and tissues to deliver and absorb oxygen, nutrients, and other substances.
what is the function of blood vessels
Blood vessels flow blood throughout the body.
what is the cardiac conduction system
A network of specialized muscle cells is found in the heart’s walls. These muscle cells send signals to the rest of the heart muscle causing a contraction. This group of muscle cells is called the cardiac conduction system
what is cardiac valves
The valves prevent the backward flow of blood. These valves are actual flaps that are located on each end of the two ventricles (lower chambers of the heart). They act as one-way inlets of blood on one side of a ventricle and one-way outlets of blood on the other side of a ventricle.
the function of cardiac valves
- The atrioventricular valves (tricuspid & mitral) permit fillining of the ventricles and prevent backflow from ventricles to the atria during ventricular contraction
- The A-V valves are anchored by the papillary muscles
- The aortic and pulmonary artery valves typically have smaller opening and withstand higher back pressures
what is Cardiac Action potentials
Cardiac Action potentials in the heart differ considerably from action potentials found in neural and skeletal muscle cells.
what is pacemaker cell
The cells that create these rhythmic impulses, setting the pace for blood pumping, are called pacemaker cells, and they directly control the heart rate
- pacemaker cells found in nodal tissue within the heart,
what is non-pacemaker cell
- positive potassium ions are leaving the cell and thereby making the membrane potential more negative inside
the difference between pacemaker and non-pacemaker cell
pacemaker cell- 3 distinct phase rapid depolarization repolarization resting potential (unstable)
non-pacemaker cells- 5 distinct phase rapid depolarization initial repolarization action potential plateau repolarization resting potential (stable)
what is coronary circulation
Coronary circulation is the circulation of blood in the blood vessels that supply the heart muscle. Coronary arteries supply oxygenated blood to the heart muscle,
what is cardiac function
Cardiac function is the ability of the heart to meet the metabolic demands of the body. The delivery of oxygenated blood and removal of cellular waste products is fundamental to life
what is the cardiac function effected by
- It is affected by the force of the ventricular contraction - the volume of blood filling the ventricle.
what are the phase of cardiac cycle
two phase=
Systole- the development of the ventricular pressure which enables sufficient pressure to open the major vaves which allow blood to flow out of that chamber.
Diastole- is when the ventricles are relaxing which it doesn’t have to be all section hearten relaxation
physiological principles that influence cardiac function
Cardiac output = blood elected from the left ventricle each minute
Stroke volume = blood ejected from the left ventricle with each cardiac cycle