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The ___T______ waves end the ECG pattern and correspond to ventricular _____repolarization______________.4
Heart rate control:Cardiac Conduction System regulates heart rate at about 75 beats/minute. However, the amount of blood pumped at any one time must adjust to the current needs of the body (more blood needed during strenuous exercise).Autonomic Nervous System regulates the cardiac conduction system to meet the needs of the body. Sympathetic division-increases heart rateParasympathetic division-decreases heart rateOther Factors the regulate heart rate:Temperature- How does increasing temperature affect heart rate?A rise in body temperature, be it from environmental factors or a medical condition, causes an increase in the heart rate. When you work out, the heart has the dual task of providing adequate blood supply to the muscles as well as to the capillaries of the skin in order to maintain body temperature. This activity can be a great burden to your heart if you are exercising in a hot environment. Hence, to reduce the stress on the heart, it is often advised to exercise early in the morning.Read more at Buzzle: Hormones- How does epinephrine affect heart rate? Increase heart rate. Strong emotions such as fear or anger cause epinephrine to be released into the bloodstream. This reaction, known as the “Flight or Fight Response” prepares the body for strenuous activity. Epinephrine is found in small amounts in the body and is essential for maintaining cardiovascular homeostasis because of its ability to divert blood to tissues under stress.Drugs-How does caffeine affect heart rate? Caffeine acts directly on the conducting system and contractile cells of the heart which increases the rate at which they depolarize. Drinking a lot of caffeine increases the heart rate.Certain ions- What is hyperkalemia?A condition caused by abnormally high levels of potassium in the blood.5