Chapter 13 Flashcards
Nervous Tissue
List the functional divisions of the nervous system
sensory nervous system - the part of the nervous system responsible for collecting information; receives sensory information that travels from the peripheral nervous system to the central nervous system (afferent)
motor nervous system - carries motor information away from the central nervous system and towards the peripheral nervous system; carries motor impulses from brain or spinal cord to muscle tissue somewhere in the body
Define nucleus
a group of neuron cell bodies grouped together in close proximity in the central nervous system
List the structural divisions of the nervous system
central nervous system (CNS) - integrates and processes nervous information; composed of brain and spinal cord
peripheral nervous system (PNS) - carries information from the body to the CNS; receives information from the CNS to cause a response in the body; composed of cranial nerves, spinal nerves, and ganglia
Define ganglion (plural = ganglia)
a group of neuron cell bodies grouped together in close proximity in the peripheral nervous system
Define nerve
a bundle of axons in the peripheral nervous system
Define afferent
information from the body traveling to the CNS
Define efferent
information traveling from the CNS to muscle tissue in the body
Define somatic
voluntary/conscious control over the structure; sensations originating in these structures can be localized
Define visceral
involuntary/unconscious control over the structure; sensations originating in these structures can not be localized
List the four basic types of nervous system information
somatic sensory - information that originates from structures you are consciously aware of and can voluntarily move
Examples: touch, pain, pressure, vibration, temperature, proprioception, vision, hearing, balance, taste, smell
visceral sensory - information comes from structures that are involuntary; unaware unless they are not functioning properly
Examples: pain from stomach and heart, smooth muscle tissue, cardiac muscle tissue, and glands
somatic motor - carry nerve impulses to skeletal muscle, causing it to contract; also called voluntary motor
Examples: walking, running, typing, moving eyes
visceral motor - carry nerve impulses to smooth muscle tissue, cardiac muscle tissue, and glands; involuntary; also called autonomic motor
Examples: breaking down of food, heart regulation, blood vessels, etc
Compare and contrast somatic afferent (somatic sensory) and visceral afferent (visceral sensory)
somatic afferent - sensory information you are consciously aware of
visceral afferent - sensory information you are unaware of
Compare and contrast somatic efferent (somatic motor) and visceral efferent (visceral motor)
somatic efferent - voluntary movements
visceral efferent - involuntary (unconscious) movements
Define neurons
nervous tissue cells that receive input from other cells, determine which parts of that information to pass on, and then send that information to other cells via action potentials; make up less than 10% of cells in the CNS, but greater than 50% of the volume
Define glial cells
nervous tissue cells that play a supporting role in the nervous system; support the proper function and health of neurons, as well as helping to modulate their activity; make up 90% of cells in the CNS
Define synapse
a space between neurons where a nerve impulse is transmitted through the junction between the end of an axon to another cell
Describe the role of the cell body (soma) in a neuron and identify them
act as the control center of the neuron; receives, integrates, and sends nerve impulses
Describe the role of dendrites in a neuron and identify them
act as receivers and conduct nerve impulses to the cell body; extend out to communicate with other neurons
Describe the role of axons in a neuron and identify them
a single long projection that extends from the cell body to carry nerve impulses to other neurons, muscle tissue, and gland cells
Describe the function of an interneuron
located in the CNS and act as the “go betweens” for other neurons; receive nerve impulses from sensory neurons and send impulses to motor neurons; play a vital role in deciding how the body should respond to stimuli; most numerous type of neuron within the nervous system
Describe the major function and the location (CNS or PNS) of astrocytes
contribute to blood brain barrier; provide structural and metabolic support to the CNS; repair damage to neurons in the CNS; located in the CNS
Describe the major function and the location (CNS or PNS) of ependymal cells
produce and circulate cerebrospinal fluid; located in the CNS (line central canal and ventricles)
Describe the major function and the location (CNS or PNS) of microglial cells
macrophages of the CNS; participate in immune response in the CNS; located in CNS
Describe the major function and the location (CNS or PNS) of oligodendrocytes
myelinate axons in the CNS; located in CNS
Describe the major function and the location (CNS or PNS) of Schwann cells
myelinate axons in the PNS; located in the PNS
Describe the function of myelin and list the portion of the neuron that is myelinated
an insulating covering that wraps around some axons in the CNS and PNS
