Neurotransmission

Question 1

What contains the nudou and metaticar apparitas of the mason?

Answer 1

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Question 2

What encases the neuron and is sometimes referred to as the somatic membrane?

Answer 2

The cell membrane; on the axon, it is known as the axonal membrane.

Question 3

What is the role of dendrites?

Answer 3

Dendrites receive information from other neurons.

Question 4

What is the function of the axon?

Answer 4

To conduct electrical activity down to the axon terminals.

Question 5

What is contained in axon terminals, and why is it important?

Answer 5

Vesicles filled with neurotransmitter (NT); essential for transmitting signals to other neurons.

Question 6

What is the difference between myelinated and unmyelinated axons?

Answer 6

Myelinated axons conduct signals faster due to the myelin sheath, which enables saltatory conduction.

Question 7

What do axons form in the PNS and CNS?

Answer 7

Axons form nerves in the Peripheral Nervous System (PNS) and tracts in the Central Nervous System (CNS).

Question 8

Where are ions located in relation to neurons?

Answer 8

Ions are located inside cellular membranes (intracellular fluid) or outside cells (extracellular fluid).

Question 9

What causes the resting potential in neurons?

Answer 9

An uneven concentration of ions between the inside and outside of the cell creates a resting potential of -70 mV.

Question 10

What ions contribute to the resting potential?

Answer 10

Potassium (K+), sodium (Na+), chloride (Cl-), and large protein molecules (A-).

Question 11

How do ions move across the membrane, and what two forces drive this movement?

Answer 11

Ions move down their concentration gradient and are influenced by electrostatic pressure.

Question 12

How do ions move across the membrane, and what forces drive this movement?

Answer 12

Ions move down their concentration gradient and are influenced by electrostatic forces, where like charges repel and opposites attract.

Question 13

What helps maintain the resting potential by regulating ion distribution?

Answer 13

The sodium-potassium pump transports Na+ out and K+ into the cell.

Question 14

What is an action potential?

Answer 14

A brief reversal of membrane potential from negative to positive, allowing signal conduction.

Question 15

At what voltage does a neuron reach the threshold to produce an action potential?

Answer 15

-55 millivolts (mV).

Question 16

What happens to the neuron’s charge during an action potential?

Answer 16

The charge briefly reverses, making the inside of the neuron positive compared to the outside.

Question 17

What causes the change in charge during an action potential?

Answer 17

Na+ ions enter the cell followed by K+ ions leaving the cell.

Question 18

What is the refractory period in a neuron?

Answer 18

A period after an action potential when the neuron cannot fire again until it resets.

Question 19

What is saltatory conduction and what structure enables it?

Answer 19

Saltatory conduction is the jumping of action potentials between Nodes of Ranvier, enabled by the myelin sheath.

Question 20

What is synaptic transmission?

Answer 20

The process where an action potential leads to neurotransmitter release from the presynaptic neuron to the postsynaptic neuron.

Question 21

How is neurotransmitter released into the synaptic cleft?

Answer 21

Vesicles bind with the presynaptic membrane, releasing neurotransmitter into the cleft through exocytosis.

Question 22

The two main types of postsynaptic receptors

Answer 22

ionotropic receptors and metabotropic receptors

Question 23

What determines whether a postsynaptic potential is excitatory (EPSP) or inhibitory?

Answer 23

Whether the neurotransmitter opens sodium (Na+, excitatory) or chloride (Cl-, inhibitory) channels.

Question 24

How are neurotransmitters removed from the synaptic cleft?

Answer 24

By reuptake into the presynaptic neuron or enzymatic degradation.

Question 25

Name an excitatory neurotransmitter and an inhibitory neurotransmitter.

Answer 25

Glutamate (excitatory) and GABA (inhibitory).

Question 26

Which disease is associated with reduced levels of acetylcholine and specific brain pathologies?

Answer 26

Alzheimer’s Disease.

Question 27

Which neurotransmitter imbalance is related to depression?

Answer 27

Abnormalities in cholinergic, catecholaminergic, and serotonergic transmission.

Question 28

Which disorder involves demyelination of axons, leading to delayed or blocked signals?

Answer 28

Multiple Sclerosis.

Question 29

What causes Parkinson’s Disease on a cellular level?

Answer 29

Loss of dopaminergic neurons in the substantia nigra, leading to dopamine imbalance.