Block

Question 1

Cerebellum

Answer 1

• 2 cerebellar hemispheres (vermin in middle)
• cerebellar cortex (gray matter)
• Arbor Vitae (white matter)
• regulation of posture and balance
• coordinate movements

Question 2

Thalamus

Answer 2

• relay station for sensory and motor information
• crude interpretation of touch, pressure, temp, and pain
• forms walls of 3rd ventricle
• organized into 7 nuclei

Question 3

Hypothalamus

Answer 3

• located inferior to the thalamus
• regulates body temp, eating and drinking, regulates emotions, regulates diurnal rhythms, other bio drives
• controls and integrates activity of the ANS and pituitary gland=> controls homeostasis
• link between nervous and endocrine system

Question 4

Epithalamus

Answer 4

1) pineal gland (melatonin)- contributes to setting biological clock
2) habenular nuclei- emotional responses to odors

Question 5

Pons

Answer 5

• Pontine Nuclei- gray matter centers connecting cerebral cortex and cerebellum-> coordinate voluntary motor output
• Apneustic Area- controls depth of breathing
• Pneumotaxic Area- controls rate of breathing

Question 6

Medulla Oblongata

Answer 6

• connects brain to spinal cord
• contains cardiovascular center
• control of respiratory rhythmicity
• swallowing, coughing, sneezing, vomiting

Question 7

Midbrain (mesencephalon)

Answer 7

• Located between pons and the dienchephalon

- Superior and Inferior Colliculi

Question 8

Internal Anatomy of spinal cord (gray matter)

Answer 8

Central canal: small opening in center of SC; contains CSF
Posterior Horns: cell bodies of somatic and visceral sensory neurons
Gray Commisure: connects posterior horns
Anterior Horns: cell bodies of somatic motor neurons
Lateral Horns: cell bodies of visceral motor neurons; found only in thoracic, lumbar and sacral regions of spinal cord

Question 9

Internal Anatomy of Spinal Cord (white matter)

Answer 9

Posterior Columns: sensory tracts (ascending)
Lateral Columns: motor and sensory tracts
Anterior Columns: motor tracts (descending)
Anterior White Commisure: connects white matter on the left and right side of SC

Question 10

Input and Output to Spinal Cord

Answer 10

Dorsal root of spinal nerve: carries afferent information
Dorsal root ganglion: cluster of sensory cell bodies outside the CNS
Ventral root: carries efferent information from anterior portion of cord
Spinal nerves: joining of dorsal and ventral roots; only 2 cm long; mixed nerves both sensory and motor information

Question 11

Reflexes

Answer 11

• Stretch Reflex: prevents over-stretching, contracts muscle that was stretched, sensed by muscle spindle, monosynaptic, ipsilateral, spinal somatic relfex
• Tendon Reflex: prevent damage from too much tension, inhibition of muscle that is contracting, tension sensed by golgi tendon organ, polysynaptic, ipsilateral, spinal, somatic reflex
• Flexor reflex: purpose to protect body part from further injury, causes flexion of affected limb, pain sensed by nociceptors, polysynaptic, ipsilateral, spinal, somatic relfex
• Crossed Extensor Reflex: stabilize body position when a painful stimulus results in flexion of opposite limb, paired with flexor reflex, extension of opposite limb, pain sensed by nociceptors, polysynaptic contralateral, spinal, somatic reflex

Question 12

Differences between ANS and Somatic NS

Answer 12

Autonomic Nervous System:
1. effectors- cardiac muscle, smooth muscle, glands
2. control- involuntary (self-governing)
3. Output- two efferent neurons exit CNS.
Somatic Nervous System:
1. Effector- skeletal muscle
2. Control- voluntary
3. Output- one efferent neuron exits the CNS
first efferent neuron exits sc and synapses with another neuron in a ganglion

Question 13

Differentiate between the parasympathetic and sympathetic NS

Answer 13

WRITE IN HERE!!!!!

Question 14

Resting Membrane Potential

Answer 14

1. Chemical force (K+ gradient) pushes K+ out
2. Electrical force (inside negative) pulls K+ in
   -High inside concentration of [K+]
   -Low inside concentration of [Na+]
   Na,K-ATPase develops and maintains steady-state ion gradients

Question 15

Channel proteins

Answer 15

• K-leak channel allows for K+ to flow with its gradient and create a negative inside potential
• chemically(ligand)-gated channels= open when a signal molecule binds to the channel protein
• mechanically-gated channels= open when membrane gets stretched
• voltage-gated channels= open when the membrane potential gets less negative (depolarized)

Question 16

Events of Action Potential

Answer 16

1. Local change in membrane potential, such local changes can be hyperpolarizing or depolarizing, ‘graded’ potentials, AP starts w/ depolarization
2. Depolarization to a threshold value causes voltage-gated Na-channels within local region to open (positive feedback loop)
3. Critical Point: shortly after Na-channels open=> they spontaneously close (inactivation)
4. Depolarization also opens a second population of voltage-gated channels (repolarization)

Question 17

Graded Potential vs. Action Potential

Answer 17

Graded potentials happens in dendrites and cell body of neurons, size varies with strength of stimulus, generated by chemically and mechanically gated channels

Question 18

Refractory Periods

Answer 18

1. Absolute Refractory Period: immediately following inactivation of Na-channels, membrane cannot be restimulated to produce AP (resetting Na-channels)
2. Relative Refractory Period: a period which anew AP can be produced but it takes a larger than normal stimulation

Question 19

Propagation of the Action Potential

Answer 19

1. Entry of Na+ produces a local current. spreads laterally to depolarize adjacent areas of membrane
2. Entry of Na+ in the ‘new’ region of membrane produces a local current that spreads to adjacent areas

Question 20

EPSP and IPSP

Answer 20

Post-synaptic electrical events are graded potentials

1. Depolarizing (if Na+ enters): Excitatory Post-Synaptic Potential EPSP
2. Hyperpolarizing (if K+ leaves, or Cl- enters): Inhibitory Post-Synaptic Potential: IPSP

Question 21

General Senses

Answer 21

receptors distributed throughout body 
1. Pain (nociceptors)
2. Temperature (thermoreceptors)
3. Touch, pressure, and body position (mechanoreceptors)
4. Chemical stimuli (chemoreceptors)
Visceral- internal organs

Question 22

Special Senses

Answer 22

Receptors congregated in specialized sense organs

1. smell (olfaction)
2. Taste (gustation)
3. sight
4. balance/equilibrium
5. Sound

Question 23

Receptive Field and Potential

Answer 23

-Discrimination bewteen two similar stimuli is dependent on the number of receptors within an area of sensory surface

Question 24

Sensory Transduction

Answer 24

1. stimulus arrives at receptor and alters membrane potential of receptor
2. receptor potential influences rate of AP production in a sensory neuron
3. APs travel CNS along afferent pathway
4. CNS interprets/processes these incoming signals

Question 25

Physiology of Vision

Answer 25

Rod transduction: 1. light photon activates rhodopsin 2. this activates an enzyme that breaks down cyclic GMP (cGMP) 3. cGMP-gated sodium channels close 4. the rod hyperpolarizes 5. glutamate release is reduced

Question 26

Summary of auditory transduction

Answer 26

1. vibration of basilar membrane at different places depending on pitch 2. movement of stereocilia on hair cells 3. opening of mechanically gated channels 4. movement of K+ into hair cells causes depolarizatino 5. depolarization causes opening of Ca2+ channels at base of hair cell 6. Ca2+ triggers exocytosis of neurotransmitter and depolarization of underlying sensory neurons in VIII nerve

Question 27

Gravity/ Equilibrium and acceleration

Answer 27

- Utricle and Saccule have hair patterns activated by gravity and acceleration - Semicircular ducts: ampulla is compartment with crista (bundle of hair) surrounded by endolymph

Question 28

Cerebrum

Answer 28

Functional areas of cerebral cortex (gray matter): 1. sensory areas, 2. motor areas, 3. association areas Frontal: reasoning, planning, part of speech and movement Parietal: perception of stimuli relating to touch, pressure, temp, pain Temporal: perception and recognition of auditory stimuli and memory Occipital: many aspects of vision Insula: integrates autonomic info, associated to visceral function