It is initiated by the P wave of the electrocardiogram. Atrial depolarization starts contraction of the cardiac muscle. When the atria contract‚ pressure within the atrial chambers increase‚ this forces more blood flow across the open atrioventricular valves‚ leading to a rapid flow of blood into the ventricles. Directional
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PSC 101 EXAM 2 Study Guide Part 1- Sensory Systems 1. Sound can best be thought of as a) compression of air molecules by an object. b) changes in air pressure produced by the vibration of an object. c) particles of energy that travel at better than 20 miles per hour. d) packets of energy. e) expansion of air molecules produced by an object as it moves through air. 2. The loudness of a sound is related to a) the amplitude of sound vibration. b) the distance between the successive
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cardiac cycle. o The P wave represents the depolarization of the atria (passage of an electrical impulse through the atria)‚ causing atrial contraction. o The PR interval represents the time period for the impulse to spread through the atria‚ atrioventricular (AV) node‚ bundle of His‚ and Purkinje fibers. o The QRS complex represents depolarization of the ventricles (ventricular contraction). o The QRS interval represents the time it takes for depolarization. o The ST segment represents the time between
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all-or none law within a single neuron‚ it does not necessarily follows the all-or-none law within an entire nerve. When you electrically stimulate a nerve at a given voltage‚ the stimulus may result in depolarization of most of the neurons but not necessarily all of them. To achieve depolarization of all of
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interaction of the channel surface and charybdotoxin residues will create a high affinity biomolecular complex. As the K+ ions enter the internal solution‚ it creates a destabilization of the bound toxin and speeds up the dissociation of charybdotoxin. Depolarization and mediation by single positively charged charybdotoxin residue will enhance this effect of K+. This blocking of a calcium-activated voltage-gated K+ channel will lead to neuronal hyperexcitability. The sting from the scorpion is usually painful
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Biology 3201 1. Unit 1- Maintaining Dynamic Equilibrium II Ch. 12 – The Nervous System (pp. 390-419) 12.1 – Structure of the Nervous System nervous system: a high-speed communication system which delivers information to and from the brain and spinal cord and all over the body. In any nervous system‚ there are 4 main components: (1) sensors: gather information from the external environment (sense organs) (2) conductors: carry information from sensors to modulators or from modulators to effectors (nerves)
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Quiz 4 Study Guide Cardiovascular Physiology Blood flow through the heart starting with the vena cavae and ending with the aorta‚ and including the Valves. IVC/SVC → Right atrium→TRIcupsid valve→ right ventricle →Pulmonary valve → Pulmonary arteries →Lungs →Pulmonary Veins→ left atrium →mitral/bicuspid valve→ Left ventricle→ aortic valve →Aorta → body SA node and AV node functions and locations SA node= upper‚ right atrium→heart rate AV node=lower‚ right atrium→ Relays cardiac impulses
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Q1) Describe and compare BOTH the similarities and differences between spatial and temporal summation Summation can be defined as the method which neurons use to communicate with each other‚ determining if the cumulative postsynaptic potential in the neuron is enough to pass the threshold for firing. There are two types of summation‚ spatial summation and temporal summation. Both types of summation are similar in that they work to strengthen the EPSP of a neuron‚ meaning they help create more postsynaptic
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Heart Rate = 60 / 0.762 = 79bpm Discussion A typical ECG tracing consists of five identifiable deflections. Each deflection is noted by one of the letters P‚ Q‚ R‚ S‚ or T. The P wave is the first waveform in a tracing and represents the depolarization of the heart ’s atria. The next waveform is a complex and consists of the Q‚ R‚
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decreases over time with an increase at 90-100s. Exercise 2 1. The lub sound occurs during the closing of the Atrioventricular valve caused by ventricular contraction. The R wave occurs during the depolarization of the ventricles. Hence the lub sound occurs because of both the depolarization and consequently the closing of the AV valves which prevent blood flow back into the atria.
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