Midterm 1

Question 1

Neuron Structure

Answer 1

Input -> Dendrite -> Cell Body -> Axon Hillock -> Axon -> Output

Question 2

Node of Ranvier

Answer 2

Inbetween myelin sheath

Question 3

3 types of Synapses

Answer 3

Axosomatic: axon - cell body
Axodendritic: axon - dendrite (most common)
Axoaxonic: - axon - axon

Question 4

The Neuron as a Battery

Answer 4

Uses the Difference in electical potential ( more positive ions outside the cell) (more negative ions inside the cell) to give the neuron a resting potential of -70mv

Question 5

Ion Channels vs Ion Pumps

Answer 5

Passive transport via gradient (Na, K, Ca, Clvs Active transport (Na, K, Ca)

Question 6

K+ Electrochemical Equilibrium

Answer 6

Electrical Gradient brings K+ into Cell

Concentration Gradient pushes K+ out of Cell

Question 7

Nernst Equation

Answer 7

calculates potential bt inside and outside of cell when K+ ions are in balance.

Eion = Equilibrium potential for ion
R = Universal gas constant
F = Faraday constant
T = Temperature
z = Valence
ln() = natural logarithm
[ion]o = outside concentration of ion
[ion]i = inside concentration of ion

Question 8

Na+ Electrochemical Equilibrium

Answer 8

both push in bc more sodium outside the cell ( conc. gradient) and more -ive inside = elec. gradient

Question 9

Na/K Pump

Answer 9

For 1 molecule of ATP
(adenosine triphosphate):
● 2 K+ in
● 3 Na+ out

Result:

Concentration gradients
● Greater Na+ outside
● Greater K+ inside

Electrical gradient
● Higher potential outside

Question 10

ACTION POTENTIAL EVENTS

Answer 10

1. At threshold, voltage-gated Na+ channels open, and positive Na+ ions flow into cell
2. As depolarization continues, even more voltage-gated Na+ channels open, increasing depolarization
3. Voltage-gated K+ channels open, and K+ ions flow out of cell
4. Voltage-gated Na+ channels close, while voltage-gated K+ channels are still open
   During hyperpolarization, another action potential cannot be generated (absolute refractory period)
5. Voltage-gated K+ channels close when the membrane is hyperpolarized (below resting potential), and the membrane potential returns to steady state at the resting potential (relative refractory period)

Question 11

Propagation of Action Potential (long distance)

Answer 11

second way the action potential travels through the neuron.

long distance signal transmission

spiking of potential conducts to nearby tissue which then excites the nearby tissue = action potential goes and so on and so on.

Question 12

Glutamate

Answer 12

Excitatory neurotransmitter

Question 13

GABA

Answer 13

Inhibatory Neurotransmitter

Question 14

Ionotropic Receptors

Answer 14

Short response time

Question 15

Metabotropic Receptors

Answer 15

Long Response time

Question 16

Strength of Post Synaptic Potential Depends on:

Answer 16

Strength of PSP at the
synapse
● Timecourse of PSP at the
synapse
● Distance to the synapse
● Time since the action
potential`

Question 17

Summation of Post Synaptic Potentials

Answer 17

PSPs then summate
● EPSPs add to the
membrane potential
● IPSPs subtract from the
membrane potential

Question 18

Major Developmental Divisions of the Brain

Answer 18

Hind Brain: Metencephalon, Myelencephalon -Brainstem
Mid Brain: Mesencephalon - Brainstem
Forebrain: Diencephalon, Telencephalon - Cerebral Cortex

Question 19

Telencephalon

Answer 19

Forebrain,

Cerebral Cortex,
Basal Ganglia,
Hippocampus

Question 20

Diencephalon

Answer 20

Forebrain,

Hypothalamus + Thalamus

Question 21

Mesencephalon

Answer 21

Midbrain,

Superior Colliculus
Inferior Colliculus
Motor nuclei

Question 22

Metencephalon

Answer 22

Hindbrain,

Pons
Cerebellum

Question 23

Myelencephalon

Answer 23

Medulla

Question 24

Cerebellum fx

Answer 24

Motor control, coordination, posture, equilibrium,

etc…

Question 25

Hypothalamus fx

Answer 25

Hormone release, body temperature, hunger, thirst, | sleep, etc

Question 26

Thalamus fx

Answer 26

Sensory-motor hub and relay, e.g.: ● Lateral geniculate nucleus: visual relay ● Medial geniculate nucleus: auditory relay

Question 27

3 Basal Ganglia (top to bottom)

Answer 27

Caudate Nucleus - Voluntary movement & goal-directed action Putamen - Motor skills & reinforcement learning Globus pallidus - Regulation of voluntary movement

Question 28

Cerebral Cortex Lobs

Answer 28

Frontal Parietal Temporal Occipital

Question 29

Sulcus that splits the two hemispheres

Answer 29

Longitudinal Fissure

Question 30

Precentral Gyrus

Answer 30

Motor control

Question 31

Cingulate Gyrus

Answer 31

Early Visual Processing

Question 32

Comissures

Answer 32

= Connections between hemispheres - Corpus Callosum - Fornix - Anterior Commisure

Question 33

Gray + White Matter

Answer 33

Gray matter: Cortical surface Cell bodies White matter: Myelinated axons

Question 34

Neuroglia

Answer 34

``` Ependymal Cells (CNS) - Produce CSF Astrocytes (CNS) - Support + Blood Brain Barrier Oligodendrocytes (CNS) - Wrap Axon in Myelin = reaches out and attaches) Schwann Cells (PNS) - Wrap axon in Myelin = Attached to Cell Body Micro Glia (CNS) - Commence Phagocytosis Satelite Cells (PNS) - Support + Blood Brain Barrier ```

Question 35

Central Nervous System

Answer 35

Brain + Spinal Cord

Question 36

Peripheral Nervous System

Answer 36

Everything other than the Brain and Spinal Cord - Somatic (Voluntary) - Autonomic (Sympathetic and parasympathetic)

Question 37

How Are Autonomic Motor Neurons diff than Somatic

Answer 37

different from somatic bc the autonomic the signals go to sympathetic or parasympathetic ganglia then go to effector vs directly to effector

Question 38

Sympathetic vs Parasympatheric

Answer 38

``` Sympathetic: ● “Fight or flight” and quick response ● Increases blood flow to skeletal muscles ● Increases heart rate ● Inhibits digestion ● Dilates pupils for far vision ``` ``` Parasympathetic ●Rest and digest”, “feed and breed”, and calmness ● Increases blood flow to gut ● Facilitates digestion ● Constricts pupils for near vision ```

Question 39

Meninges

Answer 39

Dura Mater ``` Arachnoid Mater Thin fibrous membrane with trabeculae extending through the subarachnoid space to the pia mater ``` Sub Arachnoid Space filled with CSF Pia Mater

Question 40

Ventricles of Brain

Answer 40

``` Right Ventricle Left Ventricle Choroid Plexus - produces CSF Third Ventricle Fourth Ventricle ```