Bio Psych Exam 1

what is biological psychology

A branch of psychology that studies the biological foundation of behavior, emotions, and mental processes

what techniques and theories does biological psychology draw from?

psychology
biology
biochemistry
physiology
neurosciences

what is the physiological explanation of behavior?

relates behavior to brain activity and other organs

what is the ontogenetic explanation of bhavior

describes development of the structure/behavior

functional explanation of behavior?

describes why a structure or behavior evolves as it did

evolutionary explanation of behavior?

examines a structure or a behavior in terms of evo. history

how many neurons and glial cells in the brain

80-100B

what do glia cells do?

act as maintenance workers
help immune system by acting as macrophage

how many glia are in a neuron?

10-50 per neuron

where do positive ions tend to trend?

extracellular (outside the cell) space

where do negative ions trend?

in the intracellular (inside the cell) space

what are voltage dependent channels?

protein channels that open and close in response to electrical stimulation along the membrane

what are ligand gated chanels?

channels that open and close based on direct chemical exposure

how much energy can cells use to maintain ion pumps

up to half their energy

ratio of Na:K in the sodium-potassium pump?

3 NA out
2 K in

what is ion selectivity

the process in which proteins in channels and pumps can determine what can/cannot enter, trend toward hydrophilic molecules

what do dendrites do

receive and send info to the soma

what does long dendritic length correlate with?

mental retardation

what are dendritic spines?

short outgrowths; which increase the surface area available for synapse

what is the axon hillock

junction of the axon and soma, action potentials arise here

what is the myelin sheath

fatty tissue layered around the axon, which speeds up electrical currents along the axon and insulates it

nodes of ranvier are?

unmyleinated axons

what are projection neurons?

neurons that are housed within a specific structure, but the axon extends outward from it

what are collaterals (neurons)

branches

what is the presynaptic terminal?

the end of an axon in which it releases NTs

what do synaptic vesticles contain?

neurotransmitter

afferent axons are?

axons that bring info into a structure

efferent neurons are?

neurons that carries info away from a structure

what are interneurons (intrinsic neurons)

neurons that are contained fully within a single structure

functions of astrocyte

structural and nutritional support for neurons
isolate the synapse
cleans debris
helps BBB and participates in chemical signalling

what does the oligodendrocyte do

myelinate axons

what do schwann cells do

myleinate axons

what do microglia do?

clean up debris

what types of glia cells are in the CNS?

astrocytes, oligodendrocytes, and microglia

what type of glia cell is in the PNS?

schwann cells

what does the brain need to function?

glucose, oxygen and thiamine

what does korsokoffs syndrome cause

the inability to metabolize glucose, causing neuron shrinkage

korsokoffs syndrome symptoms?

apathy, confusion, and amnesia

how does electrical potential exist in the body?

due to electrolytes like Na and Cl ions floating around the outsides and insides of cells

what is the resting potential of an AP

-70m

what happens when the membrane is depolarized?

Na and K channels open

what happens at the peak of the AP?

Na+ ion channels close
K channels open
energy trends down back toward resting state

what is summation?

the slow, gradual increase toward the threshold of excitation

what is the threshold of excitation

-30/40mV
stimulation beyond a certain mV that produces a massive depolarization of the membrane

what is the all or none law

the size, amplitude, and velocity are independent of the intensity of the stimulus that created it
action potentials either happen or dont happen

what is unique about AP frequencies?

size and strength is always the same, the actual frequency is the message

what happens during depolarization?

Na+ channels start to open
upon reaching threshold → channels fully open and Na+ rushes in

how long can channels stay closed for in depolarization before they can reopen?

around 1 milisecond

what is repolarization/hyperpolarization?

K+ channels open widely as peak approaches
cell becomes hyperpolarized and overshoots the resting membrane potential before returning to rest (70 mV)

what is the refractory period?

right after an action potental happens, neurons resist producing another AP regardless of the stimuli
stronger than normal stimulus can cause AP however

propagation of the AP?

AP starts at axon hillock, as Na+ enters the ion
AP regenerates down the axon

what is propogation?

signal reproducing itself down the length of a neuron

what is passive propagation

propagation happening down the length of an axon

what is salatory propagation?

propagation that travels through myelin fat bubbles

what can AP not do?

move backward because the previous section is in its refractory period

what is glutamate?

excitatory NT
first chemical to evolve as a NT

what is GABA? (Gamma-aminobutyric acid)

major inhibitory NT in the CNS
has synergistic effects with other GABAs and inhibitors of similar makeup

what are peptides?

2+ amino acid chains linked together

how many peptides are NTs

at least 40 different peptides

what does neuropeptide Y (NPY) do?

stimulates ravenous, frantic eating within the hypothalamus

what does CCK do

satiety neurohormone that reduces food intake

what does nitric oxide do?

it is a gas that acts as a NT while not being packaged into a synaptic vesicle
involved in blood pressure regulation

how is NT released and stored

within the vesicles (excluding Nitric Oxide)

what does exocytosis do?

release NT into the synaptic cleft, while relying on Calcium

how do postsynaptic receptors open?

upon stimulus by respective NT, like a lock and key

what are ionotropic receptors?

receptors that open/close based on a function of charge

what do metabotropic receptors require?

the activation of both g proteins and second messenger systems

what do metabotropic receptors do?

open and close ion channels
alter protein production
activate chromosomes

how do postsynatptic potentials stop?

enzyme deactivates NT, reuptake into the axon terminal

where do NTs travel after the axon terminal after termination?

to the presynaptic cleft to be recycled

what do autoreceptors not do?

open ion channels and cause changes in membrane potentials

what do negative feedback systems do?

sense chemical balances in the presynaptic cleft
regulates NT release

what isthe bell-magnedie law?

entering dorsal roots carry sensory info to the brain
exiting ventral roots carry motor info to the muscles and glands

what happens if you cut the spinal cord?

causes the brain to lose motor control over parts of the body that was served by that segment and below

what are the three layers of meninges?

dura mater
arachnoid space
pia mater

where is cerebral spinal fluid (CSF) produced at?

choroid plexus

where is CSF reabsorbed

in the arachnoid space between the meninges and brain/spinal cord

what does CSF do?

helps cushion against shock and provide buoyancy (supporting the brain)

pathway of CSF?

4 ventricles → into central canal (center channel of the spinal cord) → arachnoid space

what is hydrocephalus?

blockage of CFS flow, which causes increased pressure on the brain, spreading of infant bones, and mental retardation

how does the brain recieve nutrients?

via blood pumped through the carotid and vertebral arteries

what does the autonomic ns control?

the heart, intestines, and other organs

what does the sympathetic ns control

arousal, fight or flight response

what does the parasympathetic ns control

relax and digest, non-emergecny responses

what does the somatic ns do

conveys messages from organs to the CNS and CNS to muscles and glands

where does the spinal cord extend from and to?

from the medulla to the 1st lumbar vertebra

what is white matter?

axons and their myelin sheath

what is gray matter

neuron cell bodies without myelin

what does the hindbrain (rhombecephalon) regulate?

fundamental, life-sustaining autonomic functions

what does the medulla regulate

vital reflexes like breathing and heart rate

what is special about the pons and what does it do?

axons cross over, controls breathing

what does the cerebellum control

movement, balance, and coordination

what does damage to the cerebellum cause?

impairs timing and induces difficulty in shifting attention between auditory and visual stimuli

what does the reticular formation do?

turns on arousal and attention
controls motor areas of the spinal cord
output to cerebral cortex

what does the raphe nucleus do

mediates readiness to respond to a stimuli
sends axons to forebrain

what does the midbrain (mesencephalon) do

acts as a connection hub for the brainstem, helping process vision, hearing, eye movement, and motor control

what does the superior and inferior colliculus control?

vision and audition

what nerves control cranial nerves?

nerves 3 and 4

what does the tegmentum do?

connect forebrain and hindbrain to SC

what is the substantial niagra apart of

Part of the Dopamine pathway that mediates movement