Unit 1 Neuro Flashcards
Which steps of neuronal action potential are correct?
- Action potential initiated when cell membrane depolarizes to a threshold level
- Depolarization phase of action potential is mediated by opening voltage gated sodium channels
- Repolarization phase of action potential is driven by voltage gated potassium ion channels
- Ultimate outcome of action potential is neurotransmitter release from axon terminals.
All of them are correct
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.
True
Where do all cells receive their nutrition?
Extracellular Fluid
60% of the human body is water based fluid. Which of the following true?
1/3 of this fluid is extracellular and 2/3 of the fluid is intracellular
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.
A, B, D
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.
A,C
What does goldman equation describe?
The goldman equation describes how the diffusion potentials of individual ions are combined to form the membrane potential.
What does nearnst equation describe?
Equilibrium diffusion potential
The transport of water across epithelia is mediated by:
Combination of diffusion and osmosis. Driven by transport of sodium in the extracellular sapce nearby epithelial cells
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
A. Ionotropic receptors are ligand gated ion channels
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
All of the above are true
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
A,B,D are True
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.
True
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
A, B, C
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
B
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
All of the above are True
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.
A, B,C are True
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.
True
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
A, B, D
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
C
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)
A, C, D
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
A,B,D
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
A
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
B
