Practice Ex

Question 1

What is the neuron doctrine?

Answer 1

The neuron doctrine states that neurons are the basic structural and functional units of the nervous system, contrasting with Golgi’s reticular theory which proposed that the nervous system is a continuous network.

Question 2

What are the key components of a neuron?

Answer 2

• Soma
• Axon
• Dendrites

Question 3

What proteins are involved in the neural cell body?

Answer 3

• Rough ER
• Mitochondria

Question 4

What are Nissl stains used for?

Answer 4

Nissl stains are used to distinguish between neuronal and glial cells.

Question 5

Differentiate between neuronal cell types and glial cells.

Answer 5

• Neuronal cell types: include various types of neurons based on structure and function
• Glial cells: include astrocytes, oligodendrocytes, microglia, and Schwann cells

Question 6

What are the functions of mitochondria in neurons?

Answer 6

Mitochondria are involved in energy production and metabolic processes in neurons.

Question 7

What is anterograde transport?

Answer 7

Anterograde transport is the process of transporting materials from the neuron cell body down the axon to the synapse.

Question 8

What is retrograde transport?

Answer 8

Retrograde transport is the process of transporting materials from the axon terminal back to the neuron cell body.

Question 9

What proteins are involved in axoplasmic transport?

Answer 9

• Kinesin (anterograde transport)
• Dynein (retrograde transport)

Question 10

What is the role of the blood-brain barrier (BBB)?

Answer 10

The BBB protects the brain from harmful substances and maintains the stable environment necessary for proper neural function.

Question 11

What factors are associated with the resting membrane potential (RMP)?

Answer 11

• Ion concentration gradients
• Ion permeability
• Sodium-potassium pump

Question 12

What is the role of the lipid bilayer in neurons?

Answer 12

The lipid bilayer acts as a barrier to regulate the movement of ions and molecules in and out of the neuron.

Question 13

What is the difference between channels and pumps?

Answer 13

Channels allow passive transport of ions, while pumps actively transport ions against their concentration gradient.

Question 14

What does the Bernstein Membrane Theory explain?

Answer 14

Bernstein’s theory explains ion permeability in the neuronal membrane.

Question 15

Why is voltage compared to height in the water/electrical analogy?

Answer 15

Voltage is compared to height to illustrate potential difference, similar to how water pressure relates to height in a column of water.

Question 16

What are the four key membrane properties?

Answer 16

• Permeability
• Resistance
• Capacitance
• Conductance

Question 17

How do concentration gradients of ions contribute to resting membrane potential?

Answer 17

Concentration gradients create a difference in charge across the membrane, contributing to the RMP.

Question 18

What is the Nernst equation used for?

Answer 18

The Nernst equation calculates the equilibrium potential for a single ion based on its concentration gradient.

Question 19

What is the role of the sodium-potassium pump?

Answer 19

The sodium-potassium pump maintains the resting membrane potential by actively transporting sodium out and potassium into the neuron.

Question 20

What is electrochemical equilibrium?

Answer 20

Electrochemical equilibrium occurs when the concentration gradient and electrostatic forces for an ion are balanced, resulting in no net movement of the ion.

Question 21

What are the driving forces that affect equilibrium potential?

Answer 21

• Diffusion-concentration gradient
• Electrostatic force

Question 22

Define the absolute refractory period.

Answer 22

The absolute refractory period is the time during which a neuron cannot fire another action potential, regardless of stimulus strength.

Question 23

What is the voltage clamp technique?

Answer 23

The voltage clamp technique measures ionic currents by holding the membrane potential at a set value.

Question 24

What are the four states of voltage-gated sodium channels?

Answer 24

• Closed
• Open
• Inactivated
• Reset

Question 25

What is the significance of tetrodotoxin on sodium channels?

Answer 25

Tetrodotoxin blocks sodium channels, preventing action potentials and neuronal signaling.

Question 26

What is the function of voltage-gated potassium channels during action potentials?

Answer 26

Voltage-gated potassium channels help repolarize the membrane after depolarization.

Question 27

What is the difference between transient and persistent ionic currents?

Answer 27

Transient currents occur quickly during an action potential, while persistent currents continue over a longer duration.

Question 28

What is the role of acetylcholine at the neuromuscular junction (NMJ)?

Answer 28

Acetylcholine mediates synaptic transmission and muscle contraction at the NMJ.

Question 29

What are agonists and antagonists?

Answer 29

Agonists activate receptors, while antagonists block them. Examples include morphine (agonist) and naloxone (antagonist).

Question 30

What is Dale's Principle?

Answer 30

Dale's Principle states that a given neuron releases the same neurotransmitter at all its synapses.

Question 31

What is the role of the dopamine transporter (DAT)?

Answer 31

DAT regulates dopamine levels in the synapse by facilitating its reuptake.

Question 32

What is the function of endocannabinoids?

Answer 32

Endocannabinoids play a role in retrograde signaling and synaptic plasticity.

Question 33

What is synaptic integration?

Answer 33

Synaptic integration is the process by which multiple synaptic inputs combine to influence the postsynaptic neuron's activity.

Question 34

What are graded potentials?

Answer 34

Graded potentials are changes in membrane potential that vary in size and can lead to action potentials if they reach threshold.