Unit 1 Neuro

Question 1

Which steps of neuronal action potential are correct?

1. Action potential initiated when cell membrane depolarizes to a threshold level
2. Depolarization phase of action potential is mediated by opening voltage gated sodium channels
3. Repolarization phase of action potential is driven by voltage gated potassium ion channels
4. Ultimate outcome of action potential is neurotransmitter release from axon terminals.

Answer 1

All of them are correct

Question 2

True or False

Neurons communicate via synapses. In chemical synapses, presynaptic neurons release neurotransmitters that bind to receptors in the membrane, thus affecting membrane potential or intracellular signalling pathways in the postsynaptic cell. In less common electrical synapses, cells communicate via electrical currents that spread through gap junctions.

Answer 2

True

Question 3

Where do all cells receive their nutrition?

Answer 3

Extracellular Fluid

Question 4

60% of the human body is water based fluid. Which of the following true?

Answer 4

1/3 of this fluid is extracellular and 2/3 of the fluid is intracellular

Question 5

What is true about homestasis and feedbacks?

A. Homeostatic control systems utilize negative feedback mechanism

B. Feedback is defined as an arrangement where results of the process are fed back to the beginnning of the process

C. Positive feedback is most commonly used in physiology for blood clotting or uterine contractions during labor.

D. In physiology, negative feedback is commonly used as a central part of homeostatic control systems.

Answer 5

A, B, D

Question 6

What is true about sodium and potassium pump?

A. Na+/K+ pumps control the cell volume and prevent cell swelling

B. Na+/K+ pumps are electrogenic because during each stroke, they pump a net of one positive charge outside of the cell. This effect is completely responsible for generating the membrane potential.

C. Na+/K+ pumps are electrogenic because they generate a potassium concentration gradient which is pivotal for establishing the cell membrane potential.

Answer 6

A,C

Question 7

What does goldman equation describe?

Answer 7

The goldman equation describes how the diffusion potentials of individual ions are combined to form the membrane potential.

Question 8

What does nearnst equation describe?

Answer 8

Equilibrium diffusion potential

Question 9

The transport of water across epithelia is mediated by:

Answer 9

Combination of diffusion and osmosis. Driven by transport of sodium in the extracellular sapce nearby epithelial cells

Question 10

Select the true statement below:

A. Ionotropic receptors are ligand gated ion channels

B. Ionotropic receptors exclusively excite membranes

C. Ionotropic receptors are exclusively inhibitory

D. Neuronal inhibition is mediated by ligand-gated sodium channel

Answer 10

A. Ionotropic receptors are ligand gated ion channels

Question 11

Which of the statements are true?

A. Summation of excitatory & inhibitory postsynaptic potentials in dendrites and soma mediates information processing by individual neurons

B. Each release of an excitatory neurotransmitter in a single synapse generates a small potential (-0.5-1.0 mV) postsynaptic excitatory potential

C. Each release of an inhibitory neurotransmitter in a single synapse generates a small potential (-0.5-1.0 mV) postsynaptic inhibitory potential

D. In the soma, the excitatory and inhibitory post-synaptic potentials undergo summation and if their sum reaches the threshold, the neuron fires action potential

Answer 11

All of the above are true

Question 12

Which of the following statements about the retina is true?

A. Rods and cones are light-sensitive neurons

B. Horizontal cells, bipolar cells, and amacrine cells transmit visual information to ganglion cells

C. Rods and cones are the first cells that light encounters when it reaches the retina

D. Ganglion cells pass the visual information to the brain

Answer 12

A,B,D are True

Question 13

Is this True or Flase?

The tympanic reflex protects the cochlea from loud sounds by activating small muscles that stiffen tympanic membrane and movement of the middle ear ossicles. This reflex is mediated a neuronal circuit that involves neurons in cochlear nuclei, superior olive, and facial and trigeminal nuclei.

Answer 13

True

Question 14

Which of the following are true statements about the pontine and medullary reticular formation?

A. Medullary reticular formation inhibits antigravity muscles

B. Pontine reticular formation stimulates antigravity msucles

C. The pontine and medullary reticular formation integrate inputs from vestibular nuclei and lateral motor system and balance of their effects controls normal tonus of antigravity muscles and posture during movements

D. Medial motor system controls selectively gamma motor neurons

Answer 14

A, B, C

Question 15

What is the most accurate definition of memory in physiology?

A. The process by which an organism acquires knowledge about the world and modifies its behavior in response to changing environment

B. The process of acquisition, storage and retrieval of information or knowledge

C. The place where information is stored in the brain

D. The content of information that is stored in the brain

Answer 15

B

Question 16

True statements about short-term memory:

A. Information is typically retained in the short-term memory from seconds to few minutes

B. The capacity of short-term memory is 7+/2- items of information

C. Some of the information in the short-term memory could be retained in the reverberated neuronal circuits

D. The temporary modification of the synaptic strength can support some forms of short-term memory

Answer 16

All of the above are True

Question 17

What are all the True statements about taste sensation?

A. Taste receptors are located in taste buds, which in turn are located in several types of papillae in the oral cavity

B. Sweet tastants bind to specific G protein receptors that increase the availability of IP3 and Ca2+, which in turn trigger the release of ATP, which functions as a neurotransmitter released by some taste receptors

C. The information from taste receptors is transmitted by ganglionic neurons to the nucleus of the solitary tract. From there, the information is relayed either directly, or indirectly to the cerebral primary gustatory cortex, to parasympathetic salivatory nucleus and to the parabrachial nuclei

D. Type 2 receptor cells are the only type of cells in the taste buds. These receptors are sensitive to sweet, bitter or umami tastants.

Answer 17

A, B,C are True

Question 18

True or False

At the highest level of abstraction, the cerebral cortex can be subdivided into three functional areas. Wernicke’s area is a part of the association cortex that is essential for speech comprehension and for general intelligence.

Answer 18

True

Question 19

Which of the following statements about the gustatory sense is true?

A. Taste receptor cells are located in taste buds, which in turn are located in several types of papillae in oral cavity

B. To get an acess to tastants, receptor cells extend their microvilli into the enviornment of the oral cavity

C. The lifespan of taste receptor cells is very long and once they die, they can’t be replaced

D. The basic taste sensations are sweet, sour, bitter and umami

Answer 19

A, B, D

Question 20

Which of the following events do not belong the in the normal auditory pathway?

A. Sound waves enter the auditory canal and vibrate the tympanic membrane

B. Vibration of tympanic membrane vibrates middle ear ossicles that then vibrate the oval window of cochlea

C. Activated hair cells release neurotransmitter that activates process of sensory neurons that reside in the spiral ganglion

D. Vibrations of endolymph cause the basilar membrane to vibrate, and this makes the cells of the organ of corti to brush against tectorial membrane

Answer 20

C

Question 21

Long term storage of information requires long-term changes of brain structure. Which of the following processes could represent such a change?

A. Neurogenesis (incorportation of new neurons into existing circuits)

B. Reverberation of Action potentials in neuronal circuits

C. Synaptogenesis (formation of new synapses)

D. Synapse Pruning (removal of unused synapsees)

Answer 21

A, C, D

Question 22

Which parts of the nervous system below belong to the classification based on the what they control?

A. Somatic

B. Enteric

C. Peripheral

D. Autonomic

Answer 22

A,B,D

Question 23

Select the true statement below:

A. Ionotropic receptors are ligand gated ion channels

B. Ionotropic receptors exclusively excite membranes

C. Ionotropic receptors are exclusively inhibitory

D. Neuronal inhibition is mediated by ligand-gated sodium channel

Answer 23

A

Question 24

Select the true statement below:

A. Most of synapses in the mammalian brain are electrical synapses

B. Synapse consists of the presynaptic axonal terminal button, synaptic cleft, and post-synaptic membrane

C. In mammals, chemical synapses are rare

D. Typical neuron receives about 30 synaptic contracts from other neurons

Answer 24

B

Question 25

Which of the following statements about sensory receptors is not true?

A. Sensory receptors are neurons whose process are sensitive to various forms of physical or chemical factors

B. The information from sensory receptors is conveyed in the form of action potentials and the resulting neurotransmitter is released to the CNS

C. Mechanoreceptors, thermo receptors and pain receptors mediate somatic sensation

D. Information from sensory receptors of all sensory modalities converges on a common pathway which is called the labeled line.

Answer 25

D

Question 26

Select the true statements about the specialization and dominance of cerebral hemispheres.

a. Hemispheres communicate via axonal bundles in the corpus callosum and in he anterior commissure. They transfer sensory information, thoughts, memories and other types of information
b. The non-dominant hemisphere is better at the interpretation of music and arts and at the comprehension of non-verbal body language and voice intonation.
c. In majority of people, the right cerebral hemisphere is dominant because it contains better developed areas of cortex that control speech and skilled movements.

Answer 26

A, B

Question 27

What are the effects of cAMP?

Answer 27

Decrease Smooth muscle contraction

Increase cardiac muscle contraction

Increase in cell secretion

Increase in cell metabolism

Question 28

What are the sympathetic and parasympathetic effects on arteries ?

Answer 28

Sympathetic: Alpha 1 (Gq)

Effect: Contraction

Parasympathetic: M3 (Gq)

Mechanism: NO production from non-muscle cells like endothelium

Effect: Relaxation

Question 29

Complete the statement:

Near vision accommodation is due to activation of _____ to stimulate ___, leading to ______ of ciliary muscle

Answer 29

Near vision accommodation is due to activation of _M3 receptor____ to stimulate _Gq__, leading to ___contraction___ of ciliary muscle

Question 30

Complete the sentence:

Far vision accommodation is due to activation of _____ receptors to stimulate ___, leading to _____ ciliary muscle.

Answer 30

Far vision accommodation is due to activation of _Beta 2 adrenergic____ receptors to stimulate _Gs__, leading to ___relaxation__ ciliary muscle.

Question 31

How is epinephrine formed?

Answer 31

Phenylalanine

DOPA formed from hydroxylation

Dopamine from decarboxylation

Norepinephrine

Epinephrine

Question 32

Alpha 2 receptor is involved in which of the following mechanisms in organs?

Answer 32

smooth muscle

glands and neurons

platelets

adipocytes

Question 33

Beta 1 receptors involved in what mechansims in organs?

Answer 33

Heart

Gut

Adipocytes

Juxtoglomerular cells (increase renin secretion)