10 Nervous Tissue Flashcards
What are the two structural categories of the central nervous system?
Central nervous system and peripheral nervous system
What are the components of the central nervous system?
Brain and spinal cord
What are the structures that make up the peripheral nervous system?
Cranial nerves, spinal nerves, ganglia
How many pairs of cranial nerves?
12
How many pairs of spinal nerves?
31
What are ganglia?
Neuron cell bodies
What structural division do nerves coming off of the spinal cord belong to?
Peripheral nervous system
What direction are nerves impulses conducted on the afferent system traveling?
From a nervous receptor toward the central nervous system
What direction are nerve impulses conducted on the efferent system traveling?
Toward muscles or other effectors from the central nervous system.
What are the two functional divisions of the sensory afferent nervous system?
Somatic and visceral sensory
What functional divisions is the motor efferent nervous system divided into?
Somatic motor and autonomic motor
What at the functional divisions of the autonomic motor nervous system?
Sympathetic and parasympathetic
What are glial cells?
All of the cells that surround, support, and protect neurons
What aree neurons?
Excitable cells that transmit nerve impulses.
What are the cellular characteristics of neurons?
High metabolic rate (and thus constant need for glucose and oxygen) Extreme longevity (can live and function for over 100 years)
What is a primary tumor?
A tumor which originates in the brain
What do you call a tumor that derives from a neuron?
Trick question! You don’t! Neurons are incapable of cell division and therefore do not become tumors.
Where do tumors usually form in the brain?
From glial cells or meninges.
What is a secondary tumor?
One that originates somewhere else and then migrates to the brain. Look up teratomas!
What do dendrites do?
Carry nerve impulses towards the cell body
How may dendrites can attach to the cell body, or soma, of a single neuron?
Many, or just one
What is another name for a neuron cell body?
A soma
What is the soma?
Neuron control center
What structures are contained within a soma?
Neuron’s nucleus and organelles