WSU Biology 315 Lecture Exam #2

In ascending order, where do the synapses occur along the spinothalamic pathway?

spinal cord, thalamus, cerebral cortex

In ascending order, where do the synapses occur along the spinocerebellar pathway?

dorsal horns of spinal cord (travels through pons to cerebellum)

In ascending order, where do the synapses occur along the dorsal column pathway?

medulla, decussate toward thalamus, primary somatosensory area

autonomic ganglia

groups of autonomic nerve cells located outside the central nervous system, motor

cell body

biosynthetic center and receptive region

What are the components of the peripheral nervous systems?

consists of nerve extending from brain and spinal cord (cranial and spinal nerves)

interneurons

neurons located totally within CNS

An example of an afferent neuron is...

Touch, pain, pressure, vibration neurons

Two examples of efferent neurons are...

skeletal muscle neuron, smooth muscle neuron

What are the general somatic senses? (6 terms)

touch, pain, vibration, pressure, temperature, proprioceptive senses

What are the special somatic senses? (4 terms)

hearing, vision, smell, equilibrium

What are the general visceral senses?

stretch, pain, temperature, chemical changes, nausea, hunger

What is the only special visceral sense?

taste

What does the somatic motor system control?

skeletal muscle

What does the visceral motor system control?

regulates the contraction of smooth and cardiac muscle, secretion by glands

multipolar neuron

a neuron with more than two processes, usually many dendrites and one axon

An example of a multipolar neuron is...

interneuron (association neuron)

Bipolar neuron

two processes that extend from opposite sides of cell body

An example of a bipolar neuron is...

bipolar neuron of retina of eye

Unipolar neuron

one process that emerges from cell body and divides like an inverted letter T

An example of an unipolar neuron is...

sensory neuron

What are synapses in the nervous system?

sites of communication between cells

What are the different places on a neuron where synapses can occur?

axodendritic synapse, axosomatic synapse, axoaxonic synapse

What are action potentials?

specialized cells that conduct electrical impulses along the plasma membrane

What are the supportive cells of nerve tissue?

neuroglia (astrocyte, microglia, ependymal cells, oligodendrocytes, satellite cells, schwann cells)

Neuroglia function

support and protect neurons

microglia function

part of CNS defense, phagocytosis

ependymal cells function

help produce CSF, bear cilia that help circulate cerebrospinal fluid

oligodendrocyte function

wrap their cell processes around axons in CNS, produce myelin sheaths in Central Nervous System

satellite cell function

surround sensory neuron cell bodies within ganglia of PNS

schwann cell function

surround axons in the PNS, form myelin sheaths around axons of Peripheral Nervous System

How is myelin formed in the peripheral nervous system?

formed by schwann cells, one myelin sheath per schwann cell

How is myelin formed in the central nervous system?

oligodendrocytes coil around many different axons and produce myelin

What type of tissue makes up the epineurium?

dense irregular connective tissue (E)

What type of tissue makes up the perineurium?

dense irregular connective tissue (P)

What type of tissue makes up the endoneurium?

loose connective tissue

What is gray matter? (3 terms)

cell bodies, dendrites, axon terminals

What is white matter?

myelinated axons

What are the different ways that gray matter is organized in the central nervous system? (3 terms)

nuclei, cortex, and columns

nuclei

clusters of neuron cell bodies in CNS

columns

rows of neuron cell bodies

What are tracts in the central nervous system made of? (what are the tracts? 3 terms)

white matter (dorsal tracts, lateral tracts, ventral tracts)

What are the primary vesicles that form during brain development?

prosencephalon, mesencephalon, rhombencephalon

prosencephalon

the forebrain

mesencephalon

the midbrain

rhombencephalon

the hindbrain

What are the secondary vesicles that form during brain development?

telencephalon, diencephalon, mesencephalon, metencephalon, myelencephalon

Prosencephalon divides to form which secondary vesicles?

telencephalon, diencephalon

Rhombencephalon divides to form which secondary vesicles?

metencephalon, myelencephalon

What are the adult brain regions that develop from secondary vesicles? (8 terms)

the cerebral hemispheres, thalamus, hypothalamus, epithalamus, midbrain, pons, cerebellum, medulla

The telencephalon develops into the...

cerebral hemispheres

The diencephalon develops into the...

thalamus, hypothalamus, epithalamus

The mesencephalon develops into the...

midbrain

The metencephalon develops into the... (2 terms)

pons, cerebellum

The myelencephalon develops into the...

medulla

Meninges

fibrous layer that covers the brain and spinal cord

What type of tissue is the Dura Mater comprised of?

dense irregular connective tissue

How is the Dura Mater organized?

periosteal layer against the skull and a meningeal layer outside of that, which also covers the spinal cord

What type of tissue is the Arachnoid Mater comprised of?

connective tissue

What type of tissue is the Pia Mater comprised of?

delicate loose connective tissue

How is the Pia Mater organized?

one thin layer clings tightly to the surface of the brain, follows convolutions of cortex

What is name of the fluid found in the subarachnoid spaces?

cerebrospinal fluid (CSF)

What other structures are present in the subarachnoid space?

blood vessels that supply the brain

In the spinal cord, ascending tracts carry what type of information?

sensory information

In the spinal cord, descending tracts carry what type of information?

motor information

What type of sensory information is carried by the dorsal column pathway?

touch, pressure, conscious proprioception

What type of sensory information is carried by spinothalamic pathway?

pain, temperature, non-discriminative touch

What type of sensory information is carried by the spinocerebellar pathway?

unconscious proprioception to cerebellum

How many synapses occur along the dorsal column pathway?

three synapses (D)

How many synapses occur along the spinothalamic pathway?

three synapses (S)

How many synapses occur along the spinocerebellar pathway?

two synapses

What are the final destinations in the brain for the dorsal column pathway?

primary somatosensory area of cerebral cortex (D)

What are the final destinations in the brain for the spinocerebellar pathway?

pons to cerebellum

What are the final destinations in the brain for spinothalamic pathway?

primary somatosensory area of cerebral cortex (S)

function of precentral gyrus (Bromann's 4)

primary motor cortex

function of postcentral gyrus (Brodmann's 1-3)

primary somatosensory cortex

function of Brodmann's 5 & 7

integrates different sensory inputs

function of pyramidal cells

motor, specific ones control specific areas of the body

function of pyramidal tracts in cerebral hemispheres

control skilled movement

function of limbic system

emotions and memory

primary function of the thalamus

acts as a relay station for incoming sensory messages

lateral geniculate nucleus function of thalamus

receive input from retina, relay signals via optic tracts to primary visual centers

medial geniculate nucleus function of the thalamus

relays auditory information to cerebral hemispheres

function of the hypothalamus

main visceral control center of the body (control of ANS, regulation of body temperature, regulation of hunger and thirst sensations, controls secretion of pituitary gland and hormones, controls emotional response)

functions of the pineal gland

secretes melatonin

function of superior colliculi

visual reflexes

function of inferior colliculi

auditory reflexes

function of cerebral peduncles

contain pyramidal tracts, contain red nucleus and substantia nigra

function of superior cerebellar peduncles

output tracts, carry axons FROM cerebellum to primary motor cortex

function of periaqueductal gray matter

fright-and-flight reaction; panic behaviors (together with amygdala), mediates response to visceral pain (cold sweat, etc.), analgesia

different parts of neurons (outside to inside)

axon terminals, dendrites, cell body, axon hillock

synapse anatomical structure approaching synapse (3 terms)

axon terminal, synaptic vesicles, synaptic cleft

ventricles superior to inferior

lateral ventricles, third ventricle, fourth ventricle

cerebrospinal fluid pathway (5 terms)

choroid plexus, ventricles, lateral & medial apertures, subarachnoid space, dural sinuses

Where is cerebrospinal fluid produced?

choroid plexus

Where does the cerebrospinal fluid return to blood?

dural sinuses

dorsal column pathway (image)

dark blue left image

spinocerebellar pathway (image)

light blue left image

spinothalamic pathway (image)

right image

Inflow and outflow of information from cerebellum

superior cerebellar peduncles (outflow), middle cerebellar peduncles (inflow), inferior cerebellar peduncles (input to cerebellum)