Synapses and Sensory Receptors

Question 1

junction

Answer 1

btwn synaptic terminal and naother neuron or effector

Question 2

electrical synapses

Answer 2

electrical current flows from one neuron to another; no neurotransmitters

Question 3

chemical synapses

Answer 3

synaptic cleft; presynaptic neuron AP arrives at synaptic terminal depolarizes pm VG channels open Ca2+ diffuse into terminal inc Ca2+ causes synaptic vessicals to fuse w terminal mem NT released into cleft and diffuse across + bind to specific receptors on postsyn mem

Question 4

synaptic cleft

Answer 4

gap which seperates presynaptic neurons from postsynaptic cells (20nm)

Question 5

presynaptic neuron

Answer 5

synthesizes NT; packaged into synaptic vessicles

Question 6

acetylcholine

Answer 6

muscles, memory, learning NT

Question 7

glutamate

Answer 7

excitatory NT

Question 8

dopamine

Answer 8

mood NT

Question 9

endorphins

Answer 9

pain regulation NT

Question 10

ligand gated ion channels

Answer 10

graded potential in postsyn; mem of postsyn cell receptor protein binds + responds to NT (ligand) opens LG channels ions diffuse across postsyn mem; postsyn potential: EPSP (mem depolarizes) and IPSE (mem hyperpolarizes)

Question 11

postsynaptic neuron

Answer 11

some EPSE some IPSP; dendrites + cell body recieve info from many chem synapses

Question 12

magnitude of PSP varies based on

Answer 12

amnt of NT released by prosyn neuron; distance of synapse: one single EPSE has to travel to axon hillock may be too small to trigger AP

Question 13

temporal summation of postsyn potential

Answer 13

2 EPSP @ single synapse right after each other; interplay btwn IPSP + EPSP axon hillock integrates, mem pot = summed efect, AP threshold

Question 14

spacial summation of postsyn potential

Answer 14

EPSPs @ same time from diff syns on same postsyn; interplay btwn IPSP + EPSP axon hillock integrates, mem pot = summed efect, AP threshold

Question 15

NS embryonic dev

Answer 15

overal structure: regulated gene expression, signal transduction; brain continues to develop + remodel: competition amongst neurons for growth supporting factors, synapse elimination

Question 16

neuronal plasticity

Answer 16

neuronal connections can be modified NS remodeling based on activity; remodeling occurs @synapses: connections reinforced when activity of neuron coincides w other neurons connections weaker if activity doesn’t coincide (use it or lose it)

Question 17

short term memory

Answer 17

info briefly held released if irrelevent; stored in cerebral cortex accessed via temporary links in hippocampus; acquiring not maintaining

Question 18

long term memory

Answer 18

info stored in cerebral cortex but connections w/i cerebral cortex

Question 19

long term potentiation (LTP)

Answer 19

how memories are stored + learning happens; increase synaptic transmission strength; presynaptic neuron 2 conditions: high freq series of AP + AP arrives @ same time that postsyn cell gets depolarized by seperate stimulus; postsyn mem w glutamate receptors for NMDA + AMDA before LTP NMDA receptors to glutamate blocked Mg2+

Question 20

during LTP

Answer 20

postsyn mem depolarizes; NMDA releases Mg2+; takes in glutamate NT; influx of Ca2+; AMPA receptors also activated; both work to creae postsyn potentials strong enough to generate APs

Question 21

sensory pathway

Answer 21

ind gains info about surrounding env and internal state (sensory input); process by CNS (integration); sent to body and appropriate motor response (motor output)

Question 22

4 components of sensory pathway

Answer 22

(1) sensory reception via sense organ: stimlus/info detected by cells + receptors (2) signal transduction: conversion of stimulus to receptor potential, change in mem pot of receptor, flow of ions across mem of receptor (3) transmission: sensory info travels through NS as impulses, APs unstim to RP stim is depolarized (4) perception: brain processes info sent to it by sensory neurons

Question 23

types of sensory receptors

Answer 23

based on stimulus; ex: chemoreceptors, chem stim binds to sensory cell receptors changes ion permeability

Question 24

gustation

Answer 24

taste

Question 25

olfaction

Answer 25

smell

Question 26

cornea

Answer 26

transparent outer layer of human eye

Question 27

sclera

Answer 27

connective tissue in the human eye

Question 28

pupil

Answer 28

hole/cavity @ center of human eye

Question 29

retina

Answer 29

innermost layer w neurons and photoreceptors in human eye

Question 30

lens

Answer 30

divides eye into two cavities

Question 31

functions of human eye

Answer 31

detects light @ specific wavelengths of EMS “visible light”; eye info passed to CNS via optic nerve; brain “sees” image; brain interpretates, recognizes image

Question 32

pathway of “see”

Answer 32

light strikes retina; photoreceptors (rods + cones) gets info; bipolar cells ge tinfo; optic nerve gets info; CNs (brain) gets info; brain “sees” image

Question 33

photoreceptors

Answer 33

rods and cones

Question 34

cones

Answer 34

detect color in light

Question 35

rods

Answer 35

detect black/white (night vision); (1) light photon hits rhodopsin (2) rhodopsin activated (3) G protein signal transduction pathway (4) closes Na+ channels (no ATP) (5) hyperpolarization2