cardiovascular system Flashcards
what does the cardiovascular system allow?
rapid transport of nutrients (oxygen, amino acids, glucose, fatty acids, water, etc.)The removal of waste products of metabolism (carbon dioxide, urea, creatinine, etc.) Also hormonal control, by transporting hormones to their target organs and by secreting its own hormones (e.g. atrial natriuretic peptide).Temperature regulation occurs by controlling heat distribution between the body core and the skin. It acts as a host defence by transporting immune cells, antigen and other mediators (e.g. antibody).
what does the cardiovascular system consist of ?
- Heart ( biological pump)
- Blood
- Blood vessels / vascular system
right ventricle ?
from the pulmonary artery travels to the lungs as it is not oxygen rich. and then to the right atrium
arteries ?
carry blood away from the heart
veins ?
carry blood towards the heart , contain valves.
aorta ?
Blood leaves the left ventricle via a single large artery
what do the smallest arteires branch off into?
arterioles
blood vessels in order large to small ?
artery
arterioles
capillaries
venules
pulmonary semi lunar valve ?
located between the left ventricle ( not oxygen rich) and arteries.
atrioventricular AV valves ?
Located between the atrium and ventricle in each half of the heart are the which permit blood to flow from atrium to ventricle but not from ventricle to atrium. The right AV valve is called the tricuspid valve, and the left is called the mitral valve.
how does the opening and closing of the valves occur?
a passive process resulting from pressure differences across the valves. When the blood pressure in an atrium is greater than that in the ventricle separated from it by a valve, the valve is pushed open and flow proceeds from atrium to ventricle.
posterior vena cava ?
large vein that carries de-oxygenated blood from the lower body to the heart , to be transported to the lungs to be oxygenated.
pericardium
heart is located within a fluid filled membranous sac which allows it to contract and relax without disrupting the other organs as it is lubricated.
epicardium ?
The inner lining of the pericardium which is continuous with the covering of the heart itself
myocardium ?
the walls of the heart are composed of these cardiac cells. these are cardiomyocytes.
endocarium ?
inner surface of heart walls that are in contact with blood
how are the cardiac musle cells joined ?
gap junctions
what does this allow?
allow for the spread of excitation from one cell to another. They permit cardiac muscle to function as a whole. The myocardium also contains specialized cells that constitute the Conducting System and are essential for heart excitation.
how are the myocardium supplied with blood ?
– The Coronary Arteries
– Coronary Blood Flow
what’s the 2 phases of the cardiac cycle ?
– the contractile phase (systole)
– the relaxation (filling) phase
- (diastole) which is passive.
what causes the difference in pressure that allows the blood to be pushed into the heart chambers ?
alteration between contraction and relaxation
events leading to contraction ?
depolarisation of the plasma membrane which leads to the opening of the voltage gated Ca2+ channels. This allows the Ca2+ ions to flow into the cell from the sarcoplasmic recticlum. This leads to a rise in the cytosolic Ca2+ concentration and a contraction occurs.
what is the sarcoplasmic reticulum ?
a membrane-bound structure found within muscle cells that is similar to the endoplasmic reticulum in other cells. The main function of the SR is to store calcium ions (Ca2+).
what contracts first in the heart then what ?
atria them immediately the ventricles
