Search results for: 'Nervous control of heart rate'

Watch Later 1:32

By: HWC, Views: 6759

• Heart rate is determined by the rate of depolarizations of the sinoatrial (SA) node. • Cardiac output is directly proportional to heart rate, the greater the heart rate the greater the cardiac output. • Changes in heart rate are associated with exercise, stress or injury. Nervous ...

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Depolarization of the SA node, Action potentials of the myocardium & ANS effects

By: HWC, Views: 6504

• A typical contractile cell in the myocardium has a resting membrane potential. • The resting membrane potential of cells in the SA node is not fixed, and is known as the pacemaker potential. • The action potential of a healthy SA nodal cell has three parts: • Pacemaker potential: ...

Watch Later 1:36

Neuron structure and function - sensory neurons, association neurons & motor neurons

By: HWC, Views: 6571

• The primary function of the nervous system is to provide rapid communication within the body to maintain homeostasis. • This function underlies behaviors, thinking and control of organ functions. • The basic functions of the nervous system are provided by: • Sensory neurons • ...

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Negative Feedback Regulation of Blood Pressure

By: HWC, Views: 6646

stimulus • Blood pressure determines the flow of blood to and from capillaries. • Low blood pressure results in reduced blood flow. • High blood pressure can cause blood vessels to break. Baroreceptors • The aortic arch carries blood to the body. • The common carotids ca...

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Exercise and cardiac output

By: HWC, Views: 6468

• Cardiac output: • Maintains blood flow throughout the body. • Measure of blood volume ejected from the heart over a given time. • Determined by multiplying heart rate by stroke volume (CO = SV x HR). • Heart rate: Number of beats/min. • Stroke volume: Amount of blood eject...

Watch Later 1:58

Coronary Heart Disease

By: Administrator, Views: 9815

Coronary heart disease accounted for 23.5 percent of all deaths in the U.S. in 2008. According to the Centers for Disease Control and Prevention (CDC), about 735,000 Americans have a heart attack each year. Warning signs and symptoms include chest pain or discomfort and shortness of breath. Ex...

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Autonomic Nervous System Animation

By: Administrator, Views: 9949

Parasympathetic Division Works to conserve energy and innervate the digestive system. When activated, it: stimulates the salivary and digestive glands. decreases the metabolic rate. slows the heart rate. reduces blood pressure. promotes the passage of material through the intestines along...

Watch Later 1:55

Metabolic Rate, Heat and Thermoregulation - response to heat and cold stresses

By: HWC, Views: 6860

• A neuron group in the anterior portion of the hypothalamus controls heat balance. • Neurons in the preoptic region of the hypothalamus integrate signals that come from thermoreceptors. • The temperature control center in the preoptic region propagates control signals to two other part...

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TRH/TSH/Thyroid hormone

By: HWC, Views: 6216

Thyroid hormone production • A decline in metabolic rate caused by increased metabolic need or physical exertion stimulates the production of thyrotropin hormone releasing (TRH) hormone from the cells of the hypothalamus. • Thyrotropin hormone releasing hormone targets the thyrotrophic ce...

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