What are the names and functions of the heart chambers?
Right atrium–receives deoxygenated blood from superior and inferior venae cavae and passes this blood through the tricuspid A-V valve to the right ventricle
right ventricle–receives the oxygenated blood from the right atrium and pumps this blood through the pulmonary semilunar valve into the pulmonary trunk
left atrium–receives oxygenated blood from the pulmonary veins and passes this blood through the bicuspid A-V valve to the left ventricle
left ventricle–receives oxygenated blood from the left atrium and pumps the blood through the aortic semilunar valve into the aorta
What are the names and functions of the heart valves?
atrioventricular valves–each valve allows blood to flow from atrium into the ventricle but prevents a backflow of blood from the ventricle into the atrium. The tricuspid valve, Bicuspid valve.
Semi lunar valves–allow blood to be pumped from the ventricles into the arteries during ventricular contraction, but they prevent a backflow of blood from the arteries into the ventricles during ventricular relaxation
what are the events of the cardiac cycle?
blood flows from the AGF into the ventricles during ventricular diastole, blood is pumped from the ventricles during ventricular systole
what produces the heart sounds?
this sounds are produced by the closing of the heart valves. The 1st sound results from the closing of the atrioventricular valves during ventricular systole, the 2nd sound results from the closing of the semi lunar valves during ventricular diastole
Trace a drop of blood as it flows through the heart in the pulmonary and systemic circuits.
the pulmonary circuit carries deoxygenated blood from the right ventricle to the lungs and returns oxygenated blood from the lungs to the left atrium.
The systemic circuit carries oxygenated blood to all parts of the body except the longs and returns the deoxygenated blood to the right atrium
what composes the cardiac conduction system?
Sinoatrial node(S-A), atrioventricular node(A-V), A-V bundle, and Purkinje fibers
How is the heart rate regulated?
the rate and strength of heart contractions are regulated by the antagonistic actions of sympathetic and parasympathetic divisions of the autonomic nervous system.
Compare the structure and functions of arteries, Capillaries and veins.
F–carry blood from the heart to the capillaries
S–relatively thick muscular layer to withstand higher blood pressure
F–enable exchange of materials between blood and tissue cells
S–microscopic vessels composed of a single layer of endothelial cells
F–return blood from the capillaries to the heart
S–relatively thin muscular layer; internal valves located at intervals to prevent backflow of blood
how does the exchange of materials occur between blood in capillaries and tissue cells?
the cells of tissues are enveloped in a thin film of extracellular fluid called tissue fluid, that fill the tissue spaces and lies between the cells and the capillaries. All materials that pass between the blood and tissue cells must pass through the interstitial fluid
how does blood pressure affect the flow of blood through blood vessels?
blood pressure decreases as distance from the left ventricle increases. The farther the blood travels from the ventricle into the main arteries and lesser arteries the lower the blood pressure
compare systolic and diastolic blood pressure.
systolic: arterial blood pressure is greatest during ventricular contraction as blood is pumped into the aorta and its branches
diastolic: The lowest arterial pressure occurs during ventricular relaxation
how to cardiac output, Blood volume, and peripheral resistance affect blood pressure?
A increased in any of these factors causes an increase in blood pressure.
cardiac output: is the volume of blood pumped by the heart in 1 min.
blood volume: May decrease by severe hemorrhage, vomiting, diarrhea or reduced water intake.
Peripheral resistance: friction of blood against the walls of blood vessels
viscosity: is the resistance of a liquid to flow
what is the arterial pathway of blood from the left ventricle to the dorsal surface of the foot?
what is the venous pathway of blood from the posterior portion of the ankle to the right atrium
small saphenous, popliteal, femoral, external iliac, right atrium
what is Immunity?
specific resistance, is directed at specific pathogens or foreign cells. On immune response involves production of specific cells and substances to attack a specific invader.
How is an immune reaction started?
Activated by presence of foreign antigens:
cell mediated immunity–T cells activated and phagocytosis stimulated, direct attack against foreign antigens by chemical and physical means, destroying intracellular pathogens and foreign and diseased cells
antibody mediated immunity–B cells activated, indirect attack by producing antibodies that bind foreign antigens, bind extracellular pathogens for destruction by phagocytosis and other means
why our helper T cells so important to immunity?
helper T cells binding to the antigen and self proteins and secrete cytokines which activate the B cell