DAANCE Module 1-Basic Sciences Verified A+

DAANCE Module 1-Basic Sciences Verified A+ - Neurons: ️ Conduct nerve impulses. - Synapse: ️ Junction between two neurons. - Central Nervous System (CNS): ️ Made up of the brain and spinal cord. - Parts of the Brain: ️ Cerebrum, cerebellum, medulla oblongata. - Peripheral Nervous System (PNS): ️ Made up of sensory and motor nerves. - Cranial Nerves: ️ There are 12 cranial nerves. - Trigeminal Nerve (Cranial Nerve V): ️ Controls sensation to the teeth and jaw. - Components of the Autonomic Nervous System: ️ Sympathetic nervous system and parasympathetic nervous system. - Nervous System That "Speeds Things Up": ️ Sympathetic nervous system. - Nervous System That "Slows Things Down": ️ Parasympathetic nervous system. - Sympathetic Nervous System and the Heart: ️ Has terminations at all levels of the heart. - Stimulation of the Sympathetic Nervous System: ️ Causes vasoconstriction in general and increases heart rate. - Nervous System Important for Maintaining Blood Pressure: ️ Sympathetic nervous system. - Vasomotor Control: ️ Controlled by the sympathetic nervous system. - Vasomotor Function: ️ Controls the diameter of blood vessels. - Function of Baroreceptors: ️ Regulate blood pressure with positional changes. - Sympathetic or Adrenergic Effects: ️ Involve two effects (A and B) affecting several tissues and organs. - Alpha Effect: ️ Vasoconstriction. - Beta Effect: ️ Seen in larger organs, such as heart and lungs. - Beta 1 Activity: ️ Related to heart functions, such as increased heart rate and strength of contraction. - Beta 2 Activity: ️ Pertains to pulmonary function of bronchiolar dilation (lungs). - Parasympathetic Stimulation: ️ Increases digestive tract activity, stimulates saliva and pharyngeal secretions (atropine or Robinul can counteract stimulation). - Automaticity of the Heart: ️ The heart pumps on its own. - Four Chambers of the Heart: ️ Left atrium, right atrium, left ventricle, right ventricle. - Blood Flow into the Left Atrium: ️ Receives oxygen-rich blood from the lungs via the pulmonary vein. - Blood Flow into the Right Atrium: ️ Receives oxygen-poor blood from peripheral circulation. - Where Ventricles Receive Blood From: ️ The atria. - Ventricle Anatomy: ️ Thicker walls and larger chambers; the left ventricle has the thickest myocardium. - Right Ventricle Blood Flow: ️ Sends deoxygenated blood to the lungs. - Left Ventricle Blood Flow: ️ Sends oxygenated blood to the body/peripheral circulation. - Sources of Blood to the Right Atrium: ️ Superior vena cava (above), inferior vena cava (below), and coronary sinus (inside the heart). - Blood in Veins: ️ Considered oxygen-poor. - Blood Vessels Leading Away from the Heart: ️ Arteries. - Blood Vessels Leading to the Heart: ️ Veins. - Flow of Blood Through the Heart: 1. Right atrium fills with blood. 2. Contracts, opening tricuspid valve. 3. Right ventricle fills with blood. 4. Contracts, closing tricuspid valve/opening pulmonary valve. 5. Blood goes through pulmonary artery to the lungs. 6. Pulmonary veins return blood to the left atrium. 7. Contracts, opening mitral valve. 8. Left ventricle fills with blood. 9. Contracts, forcing blood through aortic valve into aorta and then peripheral circulation. - Closure of Valves: ️ Prevents backflow; damage results in a heart murmur or mitral valve prolapse. - Most Heart Problems: ️ Result from faulty or reduced coronary circulation. - Reduced Oxygen Supply: ️ Weakens the heart, a condition called ischemia. - Results from Ischemia: ️ Angina pectoris (chest pain). - Poor Circulation Can Cause: ️ Myocardial infarction. - Arteries Can Either: ️ Vasodilation or vasoconstriction. - Diastolic Phase in Blood Flow: ️ Occurs when the ventricles are relaxed. - Diastolic Pressure Measures: ️ The pressure in the arteries during relaxation of the ventr