Term
| 1.List three factors that assist the flow of blood through the veins |
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Definition
| 1.Three factors that assist blood flow through the veins are: Above the heart, muscle contractions push down to the heart; below the heart, muscle contractions push on the veins and force blood back towards the heart; one-way valves also prevent the backflow of blood. |
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Term
| Which chamber of the heart is the largest and strongest chamber? Explain your reasoning. |
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Definition
| Through observations of mammalian heart, it can be seen that the left ventricle is the largest and strongest chamber. This adaptation is important because the left ventricle pumps blood into the systemic and coronary systems, which together contain the most extensive system of capillary networks in the body. |
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Term
| Create a flow chart to trace the flow of blood through the heart. Start with the superior vena cava and end as blood enters the aorta. Include the names of all of the vlaves in the heart. |
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Definition
| Superior Vena Cava---> Right Atrium--->Bicuspid valve---> Right ventricle ---> Right Semilunar--> Pulmonary Arteries ---> Lungs ---> Pulmonary Veins ---> Left Atrium ---> Tricuspid Valve ---> Left Ventricle--> Left Semilunar Valve ---> Arota |
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Term
| Creat a flow chart that explains the electrical activity in a mammalian heart. Relate the events that occur to specific regions of the meart muscle in your flow chart. |
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Definition
| Electrical signal from the SA node (located in the wall of the right atrium) --> the two atria contract simultaneously --> signal reaches AV Node --> AV node transmits signal through the bundle of His --> Purkinje Fibres initiate simultaneous contraction of the right and left ventricles (starting at the apex) forcing blood towards pulmonary artery and aorta |
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Term
| What is the difference between a heart attack and a stroke? |
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Definition
A heart attack is caused when a blood clot or other object obstructs a coronary artery. This cuts off the supply of oxygen and nutrients.
A stroke occurs when there is blockage or a rupture of an artery in the brain. This disrupts the flow of oxygen and nutrients to the part of the brain behind the damaged artery. |
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Term
| List three functions of the blood, and indentify the cells involved in each. |
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Definition
| The following are classifed as functions of the blood and the cells involved in each: - transport of oxygen from lungs to cells - red blood cells - transport of carbon dioxid from cells to lungs - primarily plasma; some in the red blood cells - fight infection (part of immune system) - white blood cells - initiate blood clotting (maintaining homestasis) - plaatelets - regulating body temperature(maintaining homeostatsis_ - plasma (countercurrent heat exchange) |
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Term
| Describe the three primary pathways taken by the blood. |
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Definition
The three primary pathways are:
(a) cornary pathway, which is the route taken by blood to the heart muscle itself
(b) pulmonary circulation, which is the route taken by the blood between the heart and the lungs
(c) systemic circulation, which is the route taken by the blood from the heart to the rest of the body |
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Term
| Identify the types of cells that are destroyed by the phagocytic activity of the macrophages |
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Definition
| Macrophages are phagocytic cells found in the liver, spleen, brain, and lungs; they also ciculate in the bloodstream and interstitial fluid. These cells ingest and kill bacteria. Other white cells target body cells that have become cancerous or infected by viruses |
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Term
| How is lymph circulated in the body? How is this similar to how blood is circulated? How is it different? |
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Definition
| Lymph is circulated through a series of glands and vessels that extends throughout the body. Similarities to blood circulatory system: - lymph travels in a closed system - lymphatic vessel have valves to prevent the backflow of lymph (similar to veins) - depends on the contraction of skeletal muscles outside of the circulatory system (similar to veins) differences: - unlike the circulatory system, the pymphatic system does not have a pump |
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Term
| Describe the role of T cells in the body's response to infectious agents. |
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Definition
| In cellular immunity, a T cell that has a receptor for the particular antigen attaches to the macrophage and then goes through a process of rapid cell division. This produces a number of types of T cells. Helper T cells give off chemicals that stimulate other macrophages, B cells, and other T cells. Cytotoxic (killer) T cells bind to other cells that have been infected and destory them. Suppressor T cells that have been infected and destroy them. Suppressor T cells slow and stop the process of cellular immunity,while memory T cells remain in the bloodstream to promote faster response if the same antigen appears again. |
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Term
| The immune system helps the body resist pathogens. Identify three ways that pathogens can enter the body. |
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Definition
Pathogens can enter the body
-through the air you breathe,
-the water you drink,
-the food you eat,
-or through breaks in the skin. |
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