BIO 669 Quiz 2 Verrified Questions and Answers A+ Graded 100% Excel

BIO 669 Quiz 2 Verrified Questions and Answers A+ Graded 100% Excel Neuron is composed of - CORRECT ANSWER-cell body, dendrites, axon densely packed cell bodies in the CNS are called _____ - CORRECT ANSWER-nuclei densely packed cell bodies in the PNS are called _____ - CORRECT ANSWER-Ganglia What are dendrites? - CORRECT ANSWER-Receptive portions of the neuron; receives information What do axons do? - CORRECT ANSWER-Carry impulses away from the cell body is membrane potential about the inside of the cell or the outside? - CORRECT ANSWER-inside of the cell what is an electrochemical gradient? - CORRECT ANSWER-describes the forces affect on ion movement if allowed to become permeable a membrane when does action potential start? - CORRECT ANSWER-when a membrane is depolarized enough that it triggers voltage-gated ion channels What is a graded potential? - CORRECT ANSWER-changes in membrane potential that decreases over distance what Is a refectory period? - CORRECT ANSWER-a period immediately following stimulation that is unresponsive for some time. Reduced sensitivity What is myelin? - CORRECT ANSWER-A segmented layer of lipid material, acts as insulation. what is myelin called in the PNS? - CORRECT ANSWER-Schwann cells What are the nodes of Ranvier? - CORRECT ANSWER-gaps/regular interruptions in the myelin sheath What is saltatory conduction? - CORRECT ANSWER-The flow of ions between segments of myelin rather than alone the entire length of the axon. Like playing leap frog. What is divergence? - CORRECT ANSWER-ability of branching axons to influence many neurons What is convergence? - CORRECT ANSWER-Branches of numerous neurons converging on one or a few neurons Central Nervous System (CNS) is made up of - CORRECT ANSWER-brain and spinal cord Peripheral Nervous System (PNS) is made up of - CORRECT ANSWER-cranial nerves and spinal nerves afferent pathways are_____ - CORRECT ANSWER-ascending efferent pathways are _____ - CORRECT ANSWER-descending What does the somatic nervous system do? - CORRECT ANSWER-motor and sensory pathways that regulate voluntary motor control of the skeletal muscles What does the autonomic nervous system do? - CORRECT ANSWER-motor and sensory pathways that regulate the bodies internal environment through involuntary control or organ systems