Lecture 1: Intro to CNS and PNS Flashcards
what makes up the CNS?
brain and spinal cord
what makes up the PNS?
cranial nerves (arise from the brain)
spinal nerves (arise from the spine)
what is the functional unit of the nervous system?
a neuron
what is a soma
the cell body of the neuron
what is a synapse
spot on dentrites, where neurons communicate with each other
where do inputs of neurons occur
at the dendrites
where is the output of neurons
axon and axon terminal
what is a cluster of nerve cells located in the CNS called
nucleus or nuclei (plural)
what is a cluster of nerve cells located in the PNS called
ganglion or ganglia (plural)
What is the function of the myelin sheath on axons?
it provided insulation allowing the electrical signal from the cell body to rapidly reach the axon
what are cells that produce myelin in the CNS called?
Oligodendrocytes
what are cells that produce myelin in the PNS called?
Schwann Cells
what is white matter is composed of?
Myelinated axons
what is grey matter is composed of?
less myelin, mostly cell bodies
what are the two functional types of neurons in the PNS
sensory (affarent)
motor (efferent)
what are sensory (affarent) nerves?
“Affect - your feelings”
Carry nerve impulses towards CNS
what are motor (efferent)
Effect the world around you
carry nerve impulses away from the CNS
what are the 2 subdivisions of the PNS?
Somatic and viseral
what is the somatic division of the PNS?
go to and from the external environment
sensory:
1. general somatic afferents
- special somatic afferents
motor:
1. general somatic efferents
what are general somatic afferents?
pain, temperature, touch, proprioception
what are special somatic afferents?
vision, hearing, balance, smell
only found in cranial nerves 1, 2, 8
what are general somatic efferents
innervation of skeletal muscles
what is the visceral division of the PNS?
go to and from the internal environment
sensory:
1. general visceral afferent
- special visceral afferent
motor:
1. general visceral efferent
- special visceral efferent
what general visceral afferents?
pain and reflexes from organs, glands and blood vessels
mostly subconscious but can become conscious like heartburn
what are special visceral afferents?
taste
only found in cranial nerves 7, 9, 10
what are general visceral efferents?
innervation of smooth muscle (gut and arteries) and glands
controls sympathetic and parasympathetic subdivisions of nervous system
what are special visceral efferents?
innervation of skeletal muscle in pharynx
what is the large section of the brain we can view from the lateral perspective
cerebrum
think Bruh its big
what is the smaller section of the brain inferior to the larger section
cerebellum
“belly” of the brain
What are the convolutions on the cerebrum called and what separates them?
gyri separated by sulci
what are the convolutions on the cerebellum called, and what separates them?
folia separated by fissures
Name the three components of the brainstem?
Midbrain
pons
medulla
superior to inferior
What do you call the fissure that separates the two hemispheres of the brain?
Medial longitudinal fissure
What structure connects the two hemispheres of the brain?
Corpus callosum (white matter)
Name the 6 lobes of the cerebrum
Frontal, parietal, temporal, occipital, limbic, insula
What separates the frontal and parietal lobes?
Central sulcus
What separates the frontal and parietal lobes from the temporal lobe?
Lateral sulcus
Which of the 6 cerebrum lobes are defined besed on function?
Limbic and insula
What separates the parietal and occipital lobes?
parieto-occipital sulcus
where is the limbic lobe?
not visible with lateral view, only medial. next to corpus callosum and extends onto the medial surface of temporal lobe