Transport System Flashcards
Be able to identify all of the parts of the heart in a diagram (including chambers, valves, and associated vessels).
Vena cava, pulmonary artery, right atrium, right ventricle, aorta, pulmonary vein, left atrium, left ventricle
Know the pathway of blood (both deoxygenated and oxygenated) to, through, and from the heart (systemic and pulmonary circulation - the “double pump”)
Systemic Circulation - pumps deoxygenated blood, Starting at the vena cava blood is pumped into the right atrium then it flows through the right AV valve and into the right ventricle, through the right semilunar valve and into the pulmonary arteries
Pulmonary Circulation - pumps oxygenated blood, starting in the pulmonary veins blood is pumped into the left atrium and then flows through the left AV valve into the left ventricle then through the left semi lunar valve into the aorta which send it to the body or the coronary artery which sends it to the heart
Be able to explain the roles of valves in the heart in maintaining a one-way flow of blood and in causing pressure changes (in order to aid in the timing of blood flow in the cardiac cycle).
Open valves allow blood to flow freely through the heart. Closed valves stop blood from flowing backwards. When pressure in the atrium is higher than in the ventricle the AV valves open to allow blood to flow into the ventricle. When ventricle pressure becomes higher than atrium pressure AV valves close to prevent blood from flowing backwards
Be able to explain the events in one cardiac cycle (including systole and diastole of the atria and ventricles).
Systole is when there is a contraction. Pressure in the atrium is higher than the ventricle so the AV valve will open allowing blood to flow freely into the ventricle and the atrium will contract. Pressure in the ventricle will increase causing AV valves too close and semi lunar valves t open and ventricle contracts, moving blood into the pulmonary artery. Diastole is when the muscles are relaxed, this happens as the blood is moved to the lungs and into other chambers of the heart.
Be able to use a cardiac cycle diagram (showing pressure and volume changes in the heart) to identify pressures changes in the left atrium, left ventricle, and aorta (and make sure you know which of these structures corresponds to which pressure line in the diagram (last two slides in your heart notes presentation).
Be able to explain the control of the heartbeat (myogenic/ SA node, medulla/ nerves, and adrenal glands)
Myogenic - signal for cardiac contraction arises in the heart itself cardiac muscle can contract and relax on its own without any control by the nervous system
SA Node - SA node acts as a pacemaker, located in the right atrium starts the heart beat by generating an impulse, which travels through the walls of the atria, stimulating atria to contract from top to bottom. The impulse reaches junction between atria and ventricles and activates the AV node. The AV node “waits” for approximately 0.1 sec, then sends signals through walls of ventricle that cause ventricles to contract from the bottom up, so that blood is pushed up and out of ventricles to arteries
Medulla/ nerves - Monitors CO2 levels in the blood. IF CO2 levels rise: Medulla sends a signal through a cranial nerve called the cardiac nerve to the heart that causes SA node to fire more frequently – speeds up heart rate/ rate of contraction. As CO2 levels return to normal: Medulla sends a signal through a cranial nerve called the vagus nerve to the heart that causes SA node to fire less frequently which slows down heart rate to the myogenic rate
Adrenal Gland - the adrenal glands (part of the endocrine system - on top of kidneys) can
also speed up heart rate/ force of contraction by releasing the hormone adrenaline (epinephrine) into the bloodstream
Be able to explain how blood vessel structure is related to its function for: arteries, veins, and capillaries
Arteries - Have a narrow lumen to keep a high interior pressure. Thick walls to prevent rupturing due to the high pressures. elastic fibers to keep high pressure in between heartbeats. Walls contain collagen to help reinforce
Veins - Wide lumen to keep pressure low. Thin walls because blood is not traveling at high pressure in pulses. Contains valves to prevent blood from pooling in the veins
Capillaries - Narrow diameter, with walls only one cell thick. Contain pores to help in the exchange of materials.
Be able to identify arteries, veins, and capillaries in diagrams etc. based on structural differences (and be able to outline those structural differences as evidence for your identification)
Know the components of blood and what is transported by the blood.
Blood is composed of:
Plasma (liquid/ fluid component of the blood) ~55%
Erythrocytes (red blood cells – transport O2) ~45%
Leukocytes (white blood cells)
Phagocytes (nonspecific immunity)
Lymphocytes (specific immunity)
Platelets (involved in blood clotting)
Note: Leukocytes and platelets make up less than 1% of the blood
Be able to explain how materials are exchanged between the capillaries and tissues
Capillaries have very small diameter to decrease the area for diffusion helping decrease distance for diffusion. They have pores to help CO2 diffuse out of the capillaries into arteries and O2 diffuse from arteries into the cell
Be able to outline the role of valves in veins.
Know what atherosclerosis is and be able to explain the process of how it can cause occlusions and/ or clot formation in the coronary arteries.
Atherosclerosis is the build up of plaque in arteries, and is the cause of coronary heart disease in coronary arteries. Plaque can increase blood pressure in arteries causing them to become inflamed. Chronic inflammation can lead to lipid, cell debris, and cholesterol build up, hardening the walls making them lose elasticity. If plaque breaks off an original deposit it can damage artery walls can cause clotting in the artery which can lead to a thrombosis.
Be able to explain the causes and consequences of occlusions of the coronary arteries.
Occlusion in the coronary arteries can lead to atherosclerosis, the build up of plaque in the arteries. Of plaque falls off the original plaque deposit blood clots can form which can cause a thrombosis. Atherosclerosis can also lead to coronary heart disease.
