Memmlers Chapter 9 EXAM QUESTIONS & ANSWERS NEW UPDATE

Memmlers Chapter 9 EXAM QUESTIONS & ANSWERS NEW UPDATE Role of the Nervous System - ANSWER- -Coordinates all body systems - Detects to responds stimuli - Brain & spinal cord act as switching centers - Nerves carry messages to and from centers Central nervous system (CNS): - ANSWER- brain and spinal cord Peripheral nervous system (PNS): - ANSWER- cranial and spinal nerves Somatic nervous system - ANSWER- voluntary; skeletal muscle Autonomic nervous system - ANSWER- involuntary; smooth muscle cardiac muscle, glands Which division of the nervous system exclusively controls skeletal muscles? - ANSWER- Somatic nervous system Neurons are - ANSWER- functional cells of the nervous system what fibers extend from the neuron cell body? - ANSWER- dendrites & axons Cell body of a neuron contains - ANSWER- nucleus and organelles Dendrites - ANSWER- carry impulses toward the cell body(receive stimulus) Axons - ANSWER- carry impulses away from the cell body Some axons insulate & are protected by - ANSWER- a fatty myelin sheath Myelin sheath - ANSWER- white substance covering axon; for protection & speed of impulse In the CNS, myelin sheath is called - ANSWER- oligodendrocytes In the PNS, myelin sheath is called - ANSWER- schwann cells Types of Schwann Cells - ANSWER- neurilemma & nodes of ranvier Neurilemma - ANSWER- outer layer of myelin sheath Nodes of Ranvier - ANSWER- gap between the cells in the myelin sheath types of neurons - ANSWER- sensory, motor, interneurons sensory neurons - ANSWER- afferent; conduct impulses to the spinal cord & brain Motor neurons - ANSWER- efferent; carry impulses from the CNS to muscles & glands interneurons - ANSWER- central or association neurons; relay information from place to place within the CNS