Exam 2: Sqaurecaps + RQs + Discussion + HW + study guide

123 flashcards

Choose the membrane protein which is the main contributor to the resting membrane potential. A) Na/K pump. B) Na leak channel. C) Ca pump. D) Cl leak channel. E) K leak channel.

E) K leak channel.

Choose the correct statement about the refractory period. A) Both action and graded potentials have a refractory period. B) It is a time period. C) It happens in the subthreshold graded potential. D) Due to the plug in the ligand gated K channel. E) More than 1 above correct.

B) It is a time period.

GHK calculation. What's the equilibrium potential (Eion) when Ek = -90mV, Ena = 60mV, Pk = 0.2 and Pna = 0.8? A) -70mV B) -30mV C) 0mV D) 30mV E) 60mV

D) 30mV

Compare the somatosensory cortex with the motor cortex. Choose the correct statement. A) Both are located in the parietal lobe. B) Only the motor cortex has a homunculus. C) Both have more neurons responsible for the hand and face areas. D) Both cortices are in charge of the contralateral side of the body. E) More than 1 above correct.

C) Both have more neurons responsible for the hand and face areas. D) Both cortices are in charge of the contralateral side of the body. E) More than 1 above correct. -no motor cortex located in frontal lobe -both have a homunculus

Choose the correct statements about the brain areas associated with motor control. A) Cerebellum is the brain area initiating the movement of the skeletal muscles. B) Motor cortex and the amygdala are two brain areas involved in motor control. C) Damage neurons in the primary motor cortex creates Parkinson disease. D) Neurons in the Basal Nuclei release dopamine for motor control. E) More than 1 above correct.

D) Neurons in the Basal Nuclei release dopamine for motor control. -cerebellum does NOT initiate, that's motor cortex -amygdala ie emotion & memory motor control = motor cortex + cerebellum -parkinson's disease from damage of basal ganglia

______________________ can be of varying strengths and can add together, usually occurring in the dendrites/cell body. ______________________ are all-or-nothing and happen along the axon.

graded potentials action potentials

Voltage-gated sodium channels that propagate the action potential: a. Open in response to the membrane potential increasing to -55 mV b. Are activated by hyperpolarization c. Use the inactivation gate to remain closed at resting membrane potential d. Do not close until the action potential has reached the synaptic terminal, allowing sodium to continuously enter the neuron

a. Open in response to the membrane potential increasing to -55 mV

Select the statement that is FALSE about neurons communicating with each other: a. When the action potential reaches the synapse at the end of a neuron, calcium comes into the synaptic terminal from the surrounding area b. Neurons communicate with each other by releasing hormones such as ACTH and Prolactin c. Neurotransmitters act as ligands, binding to target receptors on the postsynaptic cell d. Ligand-gated sodium channels on the postsynaptic cell cause graded potentials which can lead to a new action potential e. All above are correct

b. Neurons communicate with each other by releasing hormones such as ACTH and Prolactin

Select the FALSE statement about an action potential. a. An action potential will not decay. b. Na+ channels open slowly and remain open at the end of depolarization. c. The propagation is about 2-4 milliseconds. d. dK+ channels open and Na+ channels close during repolarization. e. A second action potential cannot happen during the absolute refractory period.

b. Na+ channels open slowly and remain open at the end of depolarization.

Select the statement that is TRUE about the right and left sides of the brain a. The corpus callosum connects the two sides of the brain b. The left side of the brain receives visual input only from the right eye c. The right side of the brain is important for language, mathematics, and writing d. The left side of the brain is important for spatial visualization and analysis e. The speech center is located in the right side of the brain

a. The corpus callosum connects the two sides of the brain

Select the statement that is FALSE about types of long-term memory: a. Reflexive (implicit) memory is recalled automatically and does not require conscious attention b. Declarative (explicit) memory involves motor skills, rules, and procedures c. Reflexive (implicit) memory does not rely on the hippocampus like other forms of memory d. Declarative (explicit) memories are often reported verbally e. Reflexive (implicit) memories are acquired slowly, through repetition

b. Declarative (explicit) memory involves motor skills, rules, and procedures

The "jump" of the action potential from nodes of Ranvier to other nodes in myelinated axons is called _____ conduction.

saltatory

Some chemicals, like certain neurotoxins and local anesthetics, can bind to and block __ channels in the neuron membrane to weaken depolarization. Ca2+ K+ Na+ ClThree above are correct.

Na+

REM sleep is when most dreaming takes place. True False

true

What is consolidation in terms of memory? a. Moving sensory stimuli into short term memory b. Taking information from long term memory into conscious thought to use it c. Moving information from explicit memory to implicit memory d. Moving information from short term memory to long term memory e. None above is correct

d. Moving information from short term memory to long term memory

Choose the correct statements about how the sensory system distinguish the 4 properties of a stimulus. A) The auditory system could not identify the location of the stimulus. B) The lateral inhibition helps the somatosensory system to identify the intensity and duration of the stimulus. C) Your five senses distinguish the modality of the stimulus. D) Because all action potentials are the same, your somatosensory system could not identify the intensity of the stimulus. E) More than 1 above correct.

C) Your five senses distinguish the modality of the stimulus.

Choose the NOT correct statements about the rods and cones. A) There are 3 kinds of cones but only one kind of rods. B) Rods have high convergences compared with cones. C) Cones have a big receptive field compared with Rods. D) Both rods and cones have dark current. E) More than 1 above not correct.

C) Cones have a big receptive field compared with Rods.

Match the correct statements to the sympathetic system (S) and the parasympathetic system (P). Put None if neither matches. A. Activate digestive function _____. B. Dilate pupils __. C. Post synaptic neurons release E and NE __. D. Bata blocker ___. E. Have nACh-receptors in the target _. G. Activate the sweat glands____.

A - Parasympathetic B - sympathetic C - sympathetic D - sympathetic E - sympathetic G - sympathetic

Select the correct statement: a. Pressure-sensitive baroreceptors use tonic receptors which adapt slowly to the stimulus b. The sense of smell uses phasic receptors which continuously fire as long as the stimulus is present c. The thalamus receives stimulus from all of the five senses (sight, smell, taste, hear, touch) d. The three layers that the retina is made of: photoreceptors, bipolar cells, rod cells.

a. Pressure-sensitive baroreceptors use tonic receptors which adapt slowly to the stimulus smell uses special sense receptors and can adapt quickly, don't continuously fire smell-bypasses the thalamus three layers of retina = photoreceptors (rods & cones) + bipolar cells + ganglion cell

Select the correct statement about the ANS: a. In the somatic nervous system, the two neurons synapse in the somatic ganglion b. The sympathetic nervous system consists of short preganglionic and long postganglionic neurons. c. In the ANS, the two neurons synapse in the somatic motor ganglion d. In the parasympathetic nervous system, the end receptor is a nicotinic receptor.

b. The sympathetic nervous system consists of short preganglionic and long postganglionic neurons. -synapse in an autonomic ganglion -para end receptor is muscarinic

Select the correct statement about the somatic nervous system: a. The target of the somatic nervous system is smooth muscle b. The acetylcholine channels on the motor end plate are muscarinic. c. The acetylcholine channels on the motor end plate are nonselective cation channels d. End result is depolarization of the muscle as sodium ions flow slower than the potassium ions.

c. The acetylcholine channels on the motor end plate are nonselective cation channels -skeletal muscle is the target of somatic nervous system -ACh channels on motor end plate are nicotinic (non-selective ion channels)

Which of the following INCORRECTLY describes the sense of vision: a. signal travels from the retina to the optic nerve. b. After the signal passes the primary visual cortex, it goes to the thalamus c. amacrine cells are not good at detecting light intensity. d. different species can have a different number of cones.

b. After the signal passes the primary visual cortex, it goes to the thalamus thalamus --> somatosensory cortex

Please choose the correct statement regarding the receptors for acetylcholine and norepinephrine: a. Acetylcholine binds to two different receptors, nicotinic which is a GPCR and Muscarinic which is an ion channel b. Norepinephrine and ACh can bind to G Protein Couple Receptors c. nicotinic receptors are found in the somatic nervous system. They are attached to smooth muscle and are involved in initiating an action potential in the muscle d. adrenergic and cholinergic receptors are found on the target cells of somatic nervous system. e. Beta 1 nicotinic receptors are found in the heart and are involved in controlling the heart rate.

b. Norepinephrine and ACh can bind to G Protein Couple Receptors -nicotinic (ion channel), muscarinic (GPCR) -nicotinic receptors on somatic nervous system BUT skeletal muscle -only cholinergic (nicotinic) not adrenergic (a & beta) -beta 1 is NOT nicotinic but adrenergic

In the dark current model of vision, when there is light, cGMP __________ which ________ the calcium and sodium channels. a. increases, opens b. increases, closes c. decreases, opens d. decreases, closes

d. decreases, closes

More sensitive areas of skin have _____ and their respective sensory neurons exhibit _____. a. Larger receptive fields, less convergence b. Smaller receptive fields, more convergence c. Larger receptive fields, more convergence d. Smaller receptive fields, less convergence

d. Smaller receptive fields, less convergence

Choose all correct statement(s) about the auditory system. a. The tympanic membrane separates the external ear from the middle ear b. High frequencies displace basilar membrane in apex of cochlea c. There are three ossicles. They detect the acceleration of the head. d. The cochlea of the inner ear contains sensory receptors for hearing. e. Amplification of sound waves is mechanical.

a. The tympanic membrane separates the external ear from the middle ear d. The cochlea of the inner ear contains sensory receptors for hearing. e. Amplification of sound waves is mechanical.

What are the most common sympathetic receptors in target tissue? a. Muscarinic receptors b. Alpha receptors c. Beta 1 receptors d. Beta 2 receptors e. Nicotinic receptors

b. Alpha receptors

Somatic motor neurons release ____ onto _____ receptors at the motor end plate. a. Acetylcholine, muscarinic b. Acetylcholine, nicotinic c. Norepinephrine, nicotinic d. Dopamine, muscarinic e. None above is correct

b. Acetylcholine, nicotinic

Graded potential occurs where?

dendrites and cell body

action potential occurs where?

axon (Nodes of Ranvier)

saltatory conduction occurs where?

axon (myelin cells - nodes of Ranvier)

where is the Action Potential intiated?

axon hilock, axon

presynaptic _________ postsynaptic _________

axon terminal dendrite

EPSP/IPSP occur?

dendrites & cell body

LG channels occur?

dendrites & cell body (soma)

Voltage-gated Na+ channels occur

axon hillock, axon

VG channels occur?

Axon hillock & axon

voltage-gated K+ channels occur

axon hillock, axon

voltage-gated Ca2+ channels occur

axon terminal

ligand-gated Na+ channels occur

dendrites, soma (cell body)

ligand-gated K+ channels occur

dendrites, soma (cell body)

ligand-gated Ca2+ channels occur

NONE, only VG

exocytosis occurs

axon terminal

steps to reach and after AP

1. resting potential @ -70mV 2. stimulus (LG Na+ open) 3. graded potential (VG Na+ open) 4. Depolarization (Na+ move in) 5. VG Na+ close, VG K+ open 6. Repolarization (K+ move in) 7. Hyperpolarization (VG K+ close) 8. Na+ leak in (back to resting)

EPSP

excitatory postsynaptic potential -if synaptic potential is depolarizing

IPSP

inhibitory postsynaptic potential -if synaptic potential is hyperpolarizing

saltatory conduction

apparent jump of the action potential form node to node (need myelin)

continuous conduction

action potential generated along the entire length of the axon

Graded Potential =

EPSP + IPSP

Nerst Equation

61/z log (out/in)

Nerst equation vs GHK equation

-Nerst only calculated membrane potential based on ION concentrations inside & outside cell -GHK considers PERMEABILITY of the cell membrane to each ion

Influences muscle activity; inhibits unnecessary motor movements; coordinates slow sustained contractions

basal nuclei

Vital reflex centers: cardiac, vasomotor, respiratory

medulla oblongata, pons

Regulates ANS activities

hypothalamus, medulla oblongata, pons

Edits sensory information which is passed on to cerebral cortex; relays motor signals coming out of cerebral cortex

thalamus

Contains our biological clock, which regulates our daily patterns (including wake-sleep cycles)

hypothalamus

Memory, integration, interpretation, discrimination, localization; language

cerebral cortex

Contains many major reflex centers: withdrawal (flexor) reflex, stretch reflex

spinal cord

Functional system responsible for emotional behavior

limbic system = amygdala (emotion & memory) + cingulate gyrus (emotion) + hippocampus (learning & memory)

Regulates body temperature

hypothalamus

Receives and processes sensory information from receptor pathways; perception

thalamus

Involved in eye reflexes, such as pupillary reflex, consensual response, blinking

midbrain

Food intake; regulates water balance

hypothalamus

Found throughout brain stem; reticular activating system; also involved in motor activities & visceral activities

spinal cord

Controls several major endocrine functions

hypothalamus

3 kinds of sensory receptors

1. simple 2. complex 3. special sense (nonneuronal)

simple receptor

-1 cell -free nerve endings -somatosensory 9e.g. pain receptors) -unmeylinated but not all the time

complex receptor

-detects light pressure -touch & pressure -1 cell -myelinated, but not all the time

special sense receptors

-olfactory + gustatory = chemical receptors -vision (rods & cones) -auditory (hair cell receptors) -use 2 cells -myelinated

lateral inhibition ability to identify the location?

-increases the contrast b/c receptive field with the greater extend of activation and less stimulated neighbors -high firing rate neuron inhibits their neighbors so brain never receives the signal

large receptive field

high convergence low resolution advantage: less neurons disadvantage: less sensitive body parts

small receptive field

low convergence high resolution advantage: more sensitive areas disadvantage: cost a lot of neurons

rods vs cones: type of vision color or no color type of light resolution convergence

rods -peripheral vision (periphery) -black & white -motion & light (dim) -low resolution -high convergence = low acuity cones -central vision (fovea) -color -fine vision & light (bright) -high resolution -low convergence = high acuity

photochemical transduction in rods and cones

1. rhodopsin active or inactive 2. cGMP high or low 3. state of the channel (depolarized or hyperpolarized) DARK inactive rhodospin --> inc cGMP --> CNG channels open (Ca2+, Na+ move into cell) --> depolarization (cell becomes more (+)) --> inc neurotransmitter LIGHT active rhodopsin --> dec cGMP --> CNG channel closes --> hyperpolarization --> dec neurotransmitter

preganglionic neuron synpases at the

autonomic ganglion

postganglionic neuron synapses at the

target tissue

sympathetic neuron pathway

CNS releases ACH --> nicotinic receptor (postganglion cell body) --> post ganglion releases NE binding to target tissue on adrenergic receptor

parasympathetic neuron pathway

CNS releases ACH --> nicotinic receptor (postganglion cell body) --> post ganglion releases ACh onto muscarinic receptor of target tissue

2 types of autonomic receptors

adrenergic and cholinergic

adrenergic receptors

EPI & NE alpha 1, alpha 2, beta 1, beta 2, beta 3

cholinergic receptors

ACh: nicotinic and muscarinic

heart receptor response

beta 1 inc HT and force of contraction

arterioles and veins receptor response

alpha - constricts beta 2 - dilates

lungs receptor response

beta 2 bronchioles dilate - sym bronchioles constrict - para

endocrine pancreas receptor response

alpha inhibits insulin secretion - sym stimulates - para

adipose tissue

beta 3 - fat breakdown (lipolysis)

alpha 1 located

found in endocrine glands and blood vessels

alpha 2 found in

brain & periphery

beta 1 found in

heart

beta 2 found in

airway in bronchi

lengths of pre and post ganglion

parasympathetic - LONG preganglion & short postganglion sympathetic - short preganglion & LONG postganglion

adrenal sympathetic pathway

neurotransmitter is released in adrenal medulla --> blood

neurotransmitter receptors at synapse sym para

sym - adrenergic para - muscarinic

neurotransmitter at target synapse sym para

sym - norepinephrine para - ACh

ganglionic synapse sym para

sym - adrenergic para - muscarinic

Driving forces and the membrane proteins responsible for equilibrium potentials

-Resting membrane potential is determined by the concentration gradient and the cell's resting permeability to the ions. K+ leak channel Na+ leak channel Sodium Potassium pump

Definitions of depolarization, repolarization, and hyperpolarization. Ion channels responsible for each.

depolarization - dec in potential, membrane less (-), VG Na+ channel open then close repolarization - return to resting potential aftterm-66er depolarization, VG K+ open then close hyperpolarization - inc in potential; membrane more (-), Na+ leak channel

How are graded potentials generated?

-dendrites/cell body -stimulated by chemical release LG Na+ open

Characteristics of the graded potentials.

-like analog signals, they decay -good for local not long-distance -can be varying in strengths and add together -LG channels

How are action potentials generated?

-axon/axon terminal -VG channels open when reaching specific threshold

Characteristics of the action potentials

all-or-none 0 or 1 -will open VG -won't decay -all the same size -axons covered by Na+ and K+ channels

Definitions of all-or-none.

either reaches suprathreshold and past threshold and generates AP or not the strength of a response of a nerve cell or muscle fiber is not dependent upon the strength of the stimulus. If a stimulus is above a certain threshold, a nerve or muscle fiber will fire.

Refractory period.

-time period -NO AP can be generated -ion channels remain closed

Correct steps from grade potentials to action potentials, and finally to neurotransmitter releases.

neurotransmitter binds to receptor on dendrites --> GP accumulates in cell body/dendrites --> threshold met --> axon hillock initiates AP from chemical signal to electrical signal --> AP runs on axon --> reaches axon terminal --> stimulates NTs --> bind with receptors of NEXT neuron --> next neuron has GP and activate AP again

Compare Continuous conduction with Saltatory conduction

continuous - generated along entire length of axon (slower), nonmyelinated axon saltatory - jump of AP from node to node on myelinated axon (faster)

Steps of events happens in the synapse to cause neurotransmitter release.

1. Voltage-gated Ca2+ channels open to trigger neurotransmitter release 2. triggers membrane fusion of vesicle 3. exocytosis 4. NTs fuse out and go through simple diffusion and bind to receptor

Definitions of EPSP and IPSP.

EPSP ’ excitatory postsynaptic potential -If the synaptic potential is depolarizing (more +), it is called an EPSP. IPSP ’ inhibitory postsynaptic potential -If the synaptic potential is hyperpolarizing (more -), it is called an IPSP.

Brain areas associated with the motor control

frontal lobe -motor function (precentral gyrus) -motor cortex - a lot of mo

Brain areas and the general functions

frontal lobe - motor motor cortex - controls muscle prefrontal cortex - REASONING and DECISION making parietal lobe - sensory -visual for identification -auditory occipital lobe - vision -left brain controls right side of body -depth perception is recreated by brain temporal lobe - auditory

ANS control centers

centers located in the spinal cord, brainstem, and hypothalamus Autonomic nervous system controls smooth muscle, cardiac muscle, glands, and increases the chance of survival.

NTs released by ANS

sym - ACh or NE para - ACh

Structures of the spinal cord

gray matter - soma (cell bodies) white matter - tracts dorsal horn (back) - sensory input lateral horn - ANS ventral horn (front) - motor output

Sleep stages

REM - deep sleep, dream -rapid eye movement -brain is very active -fire together = write together

Functions of sleep

-dream -conserve energy YET don't conserve much -more activated -remember what you learned during the day -brain removes garbage/waste or cerebral spinal fluid cleans waste

How does the sensory system code 4 properties of the stimulus.

1. nature/modality need diff sensory to differentiate a location 2. location -auditory is by time differences -vision: hits retina at diff parts, sends signal to brain 3. intensity 4. duration

3 kinds of sensory receptors.

simple - 1 cell, free nerve endings (e.g. pain receptors) complex - 1 cell, receptor part has special structure (pacinian capsule senses pressure) -pressure & touch special sense - 2 cells, causes depolarization and NT release, diff levels of stimulus can be transferred into diff levels of depolarization

The structure and function of the lateral inhibition.

-inc resolution/sensitivity -inc contrast b/c receptive field with greater extent of activation and less stimulated neighbors -most activated neuron inhibits 2 lateral neurons stopping their release of NTs to signal brain & sensory cortex

Pain perception.

-due to neuronal signal/Action potential frequency -simple receptors -mechanical nociceptors -thermal nociceptors -polymodal nociceptors

Sound transduction from the middle ear to the inner ear.

1. sound waves transfer from outside to outer ear 2. tympanic membrane (middle ear) responds 3. inner ear (cochlea) extends it -endolymph liquid flows in on top and bottom flows out = organ of corti vibrates 2 liquids flow in diff directions sound waves --> eardrum movement --> 3 ossicles --> endolymph movement

Sounds process in the cochlear. How is the pitch/frequency coded?

-

Olfactory system and memory.

Activates different receptors, will open ion channel and cause depolarization (more +) and cause NT release and able to transfer them to action potential

Know the 2 cholinergic receptors and 5 Adrenergic receptors

adrenergic: alpha 1, 2, beta 1, 2 and 3 cholinergic: nicotinic, muscarinic

The relations between the sizes of the receptive field, convergence, and acuity.

Large receptive field ’ Low acuity ’ Low resolution ’ high convergence Small receptive field ’ High acuity ’ High resolution ’ low convergence