3. BRAIN COMM AND DEVELOPMENT

Question 1

What is the resting membrane potential of a neuron?

Answer 1

Around -70 mV.

Question 2

What happens during depolarisation?

Answer 2

The inside of the cell becomes less negative.

Question 3

What happens during hyperpolarisation?

Answer 3

The inside of the cell becomes more negative.

Question 4

What is the threshold of excitation?

Answer 4

Around -50 to -55 mV.

Question 5

What causes an action potential to fire?

Answer 5

When the axon hillock reaches the threshold potential.

Question 6

What are post-synaptic potentials (PSPs)?

Answer 6

Changes in membrane potential due to excitatory or inhibitory signals.

Question 7

What is the role of the axon hillock?

Answer 7

To integrate PSPs and initiate action potentials.

Question 8

What does “decremental” mean in PSP transmission?

Answer 8

The signal weakens as it travels.

Question 9

What is the “all or none” principle of action potentials?

Answer 9

An action potential either fires fully or not at all.

Question 10

What is the main ion involved in depolarisation?

Answer 10

Sodium (Na+).

Question 11

What happens during repolarisation?

Answer 11

Potassium (K+) ions leave the cell.

Question 12

What is saltatory conduction?

Answer 12

The jumping of action potentials between nodes of Ranvier.

Question 13

What are chemical synapses?

Answer 13

Synapses that use neurotransmitters for communication.

Question 14

What are electrical synapses?

Answer 14

Synapses that allow direct electrical signal transmission through gap junctions.

Question 15

What is a neurotransmitter?

Answer 15

A chemical that transmits signals between neurons.

Question 16

What triggers neurotransmitter release?

Answer 16

The influx of calcium (Ca2+) ions.

Question 17

What are synaptic vesicles?

Answer 17

Membrane-bound sacs containing neurotransmitters.

Question 18

What is synaptogenesis?

Answer 18

The formation of new synaptic connections.

Question 19

What is myelination?

Answer 19

The process of coating axons with myelin for faster signal transmission.

Question 20

What is dendritic branching?

Answer 20

The growth of new dendrites, creating new synapses.

Question 21

What is synaptic pruning?

Answer 21

The elimination of weak or unnecessary synapses.

Question 22

What is neuroplasticity?

Answer 22

The brain’s ability to reorganise and form new neural connections.

Question 23

What are ligand-gated ion channels?

Answer 23

Receptors that open ion channels directly when neurotransmitters bind.

Question 24

What are G-protein-coupled receptors?

Answer 24

Receptors that trigger indirect signalling pathways.

Question 25

What is reuptake?

Answer 25

The reabsorption of neurotransmitters by the presynaptic neuron.

Question 26

What is enzymatic degradation?

Answer 26

The breakdown of neurotransmitters by enzymes.

Question 27

What are agonists?

Answer 27

Substances that increase neurotransmitter activity.

Question 28

What are antagonists?

Answer 28

Substances that inhibit neurotransmitter activity.

Question 29

What is the neural plate?

Answer 29

The first observable sign of nervous system development.

Question 30

What is the neural tube?

Answer 30

A structure that develops into the CNS.

Question 31

What is neuronal migration?

Answer 31

The movement of immature neurons to their final location.

Question 32

What is differentiation in brain development?

Answer 32

The process by which neurons develop into their final form and function.

Question 33

What is apoptosis?

Answer 33

Programmed cell death during brain development.

Question 34

What is necrosis?

Answer 34

Unplanned cell death due to damage.

Question 35

What is the significance of mirror neurons in autism?

Answer 35

They may be deficient, affecting social interaction.

Question 36

What is Williams syndrome?

Answer 36

A neurodevelopmental disorder affecting social and cognitive abilities.

Question 37

What is the "use it or lose it" principle?

Answer 37

Synapses that are not used are pruned.

Question 38

How does sensory deprivation affect brain development?

Answer 38

Fewer synapses in visual areas; impaired depth perception.

Question 39

How does enriched experience affect brain development?

Answer 39

Thicker cortices, more dendrites, and more synapses.