ananandtktkty

nervous system primarily made of what

nervous system primarily made of what

nervous tissue

nervous system functions (3)

sensory input, integration, motor output

nervous system sensory input

monitoring stimuli occurring inside and outside the body

nervous system integration

process, interprets, assimilates experiences

nervous system motor output

responds, muscle contraction, glandular secretion

CNS (central nervous system)

brain and spinal cord

PNS (peripheral nervous system)

the sensory and motor neurons that connect the CNS to the rest of the body

sensory signals are picked up by __________ and carried by __________

sensory receptors, nerve fibers of PNS

motor signals are carried _________________

away from CNS

motor signals function

innervates muscles and glands

two main PNS regions for sensory input and motor output

somatic body region and visceral body region

four main subdivisions of PNS

somatic sensory, visceral sensory, somatic motor, visceral motor

somatic sensory

receives sensory information from skin, fascia, joints, skeletal muscles, special senses

visceral sensory

receives sensory information from viscera

somatic motor

"voluntary" nervous system: innervates skeletal muscle

autonomic motor

"involuntary" nervous system: innervates cardiac muscle, smooth muscle, glands

glial cells

cells in the nervous system that support, nourish, and protect neurons

glial cells are found where

both the CNS and PNS

are glial cells capable of mitosis?

yes

are there more neurons or glial cells?

glial cells

are glial cells capable of impulse trans?

no

glial cell types in CNS

astrocytes, ependymal cells, microglia, oligodendrocytes

glial cell types in PNS

satellite cells, neurolemmocytes

Astrocytes

Provide structural and metabolic support for neurons.

Astrocyte shape

star

most abundant type of glial cell

astrocytes

blood-brain barrier

Blood vessels (capillaries) that selectively let certain substances enter the brain tissue and keep other substances out

what is the blood brain barrier made of (2)

astrocytes and capillaries

where are 3 places the blood brain barrier is absent?

choroid plexus, hypothalamus, pineal gland

Espendymal Cells function

produce CSF (cerebrospinal fluid)

espendymal cells form what with blood vessels

choroid plexus

espendymal cell structure

cuboidal epithelial cells

microglial cells

extremely small glial cells that remove cellular debris from injured or dead cells

which type of glial cells have phagocytic activity?

microglial cells

are microglial cells abundant?

no

oligodendrocyte cells

Form myelin sheaths (protective covering) inaxons; insulation, protection, nourishment

oligodendrocyte cells structure

Large cells with globular bodies & slenderprojections

satellite cells

Regulate nutrient & waste exchange**similar in function to astrocytes

satellite cells structure

flattened cell clustered around neuronal cell bodies in a ganglion

Neurolemmocytes (Schwann cells)

myelinate (surround with myelin) axons in the PNS

Neurons

a nerve cell; the basic building block of the nervous system

neuron function

Capable of transmitting electrical impulses

do neurons undergo mitosis

no, they are amitotic

nuclei

clusters of cell bodies in the CNS

Ganglia

clusters of cell bodies in the PNS

Bundles of axons in the CNS are called

tracts

Bundles of axons in PNS are called

fibers

sensory neurons

neurons that carry incoming information from the sensory receptors to the brain and spinal cord (CNS)

motor (efferent) neurons

originate in CNS, -travel to an effector (muscle or gland)

interneurons

-located between motor and sensory neurons

-found in CNS

-make up 99.98% of neurons in body

SAME DAVE : Spinal cord nerve origins

Sensory: Afferent, Motor: Efferent, Dorsal: Afferent, Ventral: Efferent

Myelination

Process by which part of an axon is wrapped withmyelin sheath

myelin made of what

mostly fat, plasma membrane of glial cells

what gives white color in CNS and PNS

myelination

myelination functions (3)

insulation, protection, nourishment

axon diameter

the larger the diameter, the faster the impulse

saltatory conduction

Rapid transmission of a nerve impulse along an axon, resulting from the action potential jumping from one node of Ranvier to another, skipping the myelin-sheathed regions of membrane.

A node of Ranvier (myelin sheath gap)

is a bare region of axonal membrane in myelinated axons only.

nerve structure

cable like organs, Consist of numerous axonswrapped in connective tissue- Most nerves contain bothmyelinated andnonmyelinated sensory andmotor axons- Axon is surrounded bySchwann cells

neuron =

nerve cell

nerve fiber =

long axon

nerve =

bundle of axons in PNS

gray matter

Short nonmyelinated interneurons

• Cell bodies of interneurons andmotor neurons

• Neuroglia

white matter

• Fiber tracts of myelinated and nonmyelinated axons

• Neuroglia

Synapses

specialized junctions where axons contact other neurons, muscle cells or glands

In neurons, synapses occur

anywhere

Axon-dendrite synapse is _______ (more/less) common

more

electrical synapse

a type of synapse in which the cells are connected by gap junctions, allowing ions (and therefore the action potential) to spread easily from cell to cell

chemical synapse

More common*Signaling molecule"neurotransmitter"Ach is the most commonunidirectional

neuronal integration

structural link between PNS and CNS occurs in gray matter of CNS

spinal pathways are

rapid

cortical pathways are

slower

Where are ganglia located?

PNS

The major parts of the brain are (4)

brain stem, cerebellum, diencephalon, cerebrum

Regions of the Diencephalon (3)

thalamus, hypothalamus, epithalamus

regions of brainstem (3)

midbrain, pons, medulla oblongata

dura mater

thick, outermost layer of the meninges surrounding and protecting the brain and spinal cord

arcachnoid mater

s spider web filamentous layer, middle

Pia mater

a thin vascular layer adherent to contours of brain

CSF produced by

choroid plexus

csf functions (3)

buoyancy, protection, chemical stability

ventricles are what

spaces

If CSF cannot circulate or drain properly a condition called what develops

hydrocephalus

Longitudinal fissure separates

2 cerebral hemispheres

Fissures are

deep grooves

sulcus are the

shallow grooves

gyrus are the

elevated folds (like gyros)

surface layer of gray matter is called the

cortex

Left brain do what (4)

speech, verbalization, math, logic

right brain do what (3)

visual-spatial skills, intuition, emotion

Frontal function

voluntary motor for planning, mood, smell and social judgment

parietal functions

sensory in shapes, textures, speech

occpital is

optical

temporal do what

contains areas for hearing, emotional behavior, learning, memory, smell

insula does what

memory and taste