Lecture 5 - Nervous system Flashcards
Neuron
Functional unit of nervous system
Sensory neuron
Afferent
Motor neuron
Efferent
Soma
Cell body
Dendrites
Input receiving portion
Axon
Long extension that carries information
Action potential
Electrical signal
Neural or glial cells
Glue that holds all the neurons together - protecting nervous tissue
Somatic
conscious/voluntary awareness
Visceral
Sensation/response that we are not responsible for
Unconscious/involuntary
Functions of the NS (3)
Sensory function
Integrative function
Motor function
Sensory function (3)
Detect internal stimuli
Detect external stimuli
Carry information to the brain via sensory (afferent) neurons
Integrative function (3)
Processing of sensory information
Analyzing and making decisions regarding appropriate responses
Neurons which serve this function are called “interneurons”
Motor function (3)
Responding to integration decision
Neurons that serve this function are motor (efferent) neurons
Carry information out of the brain and spinal cord
Central nervous system (6)
- Brain and spinal cord
- Control center for the entire NS
- Processing and integrating of sensory information
- Planning and coordinating responses to stimuli
- Providing short term control over activities of other systems
- Immediate response
Peripheral nervous system (5)
- Neural tissue outside the CNS
- Links CNS with sense organs and other systems
- Nerves have an afferent and efferent division
- Cranial nerves (emerging from brain)
- Spinal nerves (emerging from spinal cord)
2 subdivisions of the PNS
SNS = somatic nervous system ANS = autonomic nervous system
Somatic nervous system (3)
- Controls skeletal muscle contraction
- Sensory neurons convey information from cutaneous and special sense receptors primarily in the head, body wall and extremities
- Motor neurons from the CNS conduct impulses to skeletal muscles only
T or F: somatic pathway is only one motor neuron
TRUE
Axon as long as the location it’s going to
Autonomic nervous system (3)
- Control visceral functions
- Regulate smooth muscle, cardiac muscle, and glandular activity
- Outside of our conscious control (involuntary)
T or F: motor pathway will always contain 2 neurons in series
TRUE
between the spinal cord and the end point
Sensory neurons convey homeostatic information from ______ ______ _____ _____ … to ____ ___ ___
Receptors primarily in the viscera to the CNS
Motor neurons conduct impulses to ____ ____ ____
Smooth muscle, cardiac muscle and glands
Motor portion consists of 2 pathways
Sympathetic
Parasympathetic
2 main types of cells in the NS
Neurons
Neuroganglia
Neuron (role)
Nerve impulse conduction
Neuroglia (role)
Support and protect the NS
Multipolar neuron
Several extensions branching out of cell body
Bipolar neuron
Two extensions coming out of the cell body
Unipolar neuron
One extension coming out of the cell body (input & output)
Types of neuroglia in the CNS (4)
Astrocytes
Oligodendrocytes
Microglia
Ependymal cells
Types of neuroglia in the PNS (2)
Satellite cells
Schwann cells
