Bio exam 4

noticia

knowledge

ascensus

advancement

fiducia

trust

3 nervous system functions

sensory input, integration, motor output

CNS

integration (process and interpret)

PNS

carries message to and from spinal cord and brain

sensory words

afferent, brings impulse to brain

motor words

efferent, carries impulse away from the brain

sympathetic

part of autonomic

fight, flight, fright

parasympathetic

resting and digesting

supporting cells

cells that surround and wrap neurons

neurons

excitable cells that transmit electrical signals

ependymal cells (2)

CNS, produce and circulate CSF

astrocytes (3)

CNS, largest and most numerous

maintain blood-brain barrier

oligodendrocytes

myelination of CNS axons

microglia

CNS phagocytic cells

satellite cells

surround soma with ganglia

schwann cells

myelinate axons of PNS

(repeated wrapping coats and insulates axon)

dendrites

extend from body, carrying incoming info

axon

only one, carries outgoing info

tracts vs nerves

tracts = CNS

nerves = PNS

armlike extensions from the soma (dendrites and axons)

axons function

secrete neurotransmitters from terminals, generate action potentials

anterograde

toward axon terminal

retrograde

away from axon terminal

myelin sheath functions

protection, insulate, and increases nerve impulse speed

myelin formation

from schwann cells in PNS

-schwann envelops axon and makes layers

nodes of ranvier function

axon collaterals (side branches) emerge, increase speed

CNS axons

oligodendrocytes make myelin sheath, has myelinated and unmyelinated

neurilemma is where

only in PNS neurons

white vs gray matter

gray is mostly soma and unmyelinated

multiple sclerosis

autoimmune disease in young adults

myelin sheath becomes nonfunctional

loss of muscle control

MS diagnosis

2 lesions in brain/spinal cord, CSF testing

two nerve classifications

structural and functional

structural nerve classifications

multipolar, bipolar, unipolar

bipolar nerve

two processes (axon and dendrite)

multipolar nerve

three or more processes

unipolar

single, short process

function nerve classifications

sensory, motor, and interneurons

axodendritic synapse

synapse between axon and dendrite

axosomatic synspase

synapse between axon and soma

axoaxonic synapse

synapse between axon to axon

electrical synapse function

less common than chemical

arousal from sleep, mental attention, emotion, memory

synaptic cleft characteristics/function (3)

fluid filled space separating the presynaptic and postsynaptic neurons

chemical event

ensures one direction communication

4 chemical classifications of neurotransmitters

ACh, amino acids, peptides, novel messengers

6 amino acid neurotransmitters

dopamine, norepinephrine, epinephrine, serotonin, histamine, and melatonin

dopamine

feel good

dopamine stimulation

L-dopa and amphetamines

dopamine reuptake

inhibited by cocaine

dopamine deficiency

parkinsons and schizophrenia

norepinephrine

feel good

norepinephrine release

amphetamines

norepinephrine reuptake

inhibited by Tricyclic antidepressants and cocaine

norepinephrine deficiency

depression

serotonin

mood, sleep, appetite

serotonin stimulation

ecstasy

serotonin reuptake

inhibited by LSD and Prozac

serotonin deficiency

anxiety and depression

peptide neurotransmitters

endorphins and enkephalins

causes you to feel good and inhibit pain

mostly white matter

brain

mostly gray matter

spinal cord

what is highly irritable

neurons

voltage

measure of potential energy generated by separated charge

potential differnce

voltage measured between two points

current

the flow of electrical charge (ions) between two points

resistance

hinderance to charge flow (provided by plasma membrane)

insulator

substance with high electrical resistance

conductor

substance with low electrical resistance

leakage ion channels

always open (nongated)

3 types of gated channels

chemical, voltage, mechanical

voltage gated channels

open and close in response to changes in membrane potential

gated channels flow

gradients from high to low concentration

-along electrical gradients toward opposite electrical charge

depolarzation

reduction in membrane potential toward zero

(interior becomes less negative than -70)

(increases probability of nerve impulse)

hyperpolarization

increase in membrane potential (away from zero)

divergance

creates a broad distribution from single input

(one nerve to many)

parallel processing

processing of same event by multiple neurons simultaneously

convergence

allows multiple inputs to control a single output

reverberatoin

provides positive feedback loop

(continues until fatigue or inhibited)

nerve fiber classification (3)

diameter, degree of myelination, and speed of conduction

group A fibers

fast, large diameter, myelinated

group B fibers

medium speed, lightly myelinated ANS fibers

group C fibers

slow unmyelinated ANS fibers

parts of diencephalon

thalmus, hypothalmus, pituitary gland

parts of brain stem

mid brain, pons, medulla

5 lobes of cerebrum

frontal, parietal, temporal, occipital, insula

central sulcus

separates frontal and parietal lobes

cerebral % of mass

83%

gyrus

hills, look like noodles

left hemisphere

right hand dominant, language math and logic

right hemisphere

left handed or ambidextrous, visual spatial skills, intuition, emotion, arts and music

association areas

memory areas, interprets stim

primary somatosensory

receives info from skin and skeletal muscles, spatial discrimination

somatosensory association

integrates sensory info, forms understanding of stim, determines size texture and relation of parts

wernickes

sound out words and send instructions to brocas

premotor cortex

controls learned, repetitious or patterned motor skills

primary motor cortex

conscious control over precise, skilled, voluntary movements

brocas area

motor speech (directs muscles of tongue)

prefrontal cortex

intellect, cognition, recall, personality, judgement, reasoning

lateral prefrontal cortex

language comp and word analysis

lateral and ventral temporal lobe

auditory and visual aspects of language

general/common interpretation area

integrate incoming signals into a single thought