Lecture 2. Anatomy & physiology of the nervous systems

Question 1

Question: What is the initial input information for neuronal function?

Answer 1

Answer: Neurotransmitters acting on receptors in dendritic spines.

Question 2

Question: What is the term for the process involving a change in the electrical charge across the neuronal membrane?

Answer 2

Depolarisation

Question 3

Question: What are the consecutive steps after depolarisation in neuronal function?

Answer 3

Answer: Action potential generation and propagation.

Question 4

Question: In neuronal communication, neurotransmitter release signals to which three main targets?

Answer 4

Answer: Neurons, glands, and muscles.

Question 5

Question: Name neurotransmitters in the central nervous system (CNS).

Answer 5

Answer: Glutamate, GABA, serotonin, dopamine, noradrenaline.

Question 6

Question: Name neurotransmitters in the peripheral nervous system (PNS).

Answer 6

Answer: Noradrenaline, acetylcholine.

Question 7

Question: What is the neuronal membrane more permeable to, K+ than Na+?

Answer 7

The membrane is more permeable to K+ than Na+.

Question 8

Question: What happens during the stage when electrical force opposes K+ outflow and favors Na+ inflow?

Answer 8

Answer: Resting membrane potential develops.

Question 9

Question: How are Na+ and K+ gradients maintained in the neuronal membrane?

Answer 9

Na+/K+ pumps maintain Na+ and K+ gradients.

Question 10

Question: What characterizes the rising phase of a neuronal action potential?

Answer 10

Answer: Depolarization occurs with Na+ influx via voltage-gated Na+ channels, which later inactivate.

Question 11

Question: What are the two subtypes of the refractory period in the rising phase of action potential?

Answer 11

Answer: Absolute and relative refractory periods.

Question 12

Question: What characterizes the falling phase of a neuronal action potential?

Answer 12

Answer: Repolarization occurs with K+ efflux via voltage-gated K+ channels.

Question 13

Question: What is the initial step in neuron activation related to action potential?

Answer 13

Answer: Recruitment of Na+ channels.

Question 14

Question: What follows the recruitment of Na+ channels in the process of neuron activation?

Answer 14

Answer: Generation of the action potential.

Question 15

Question: What is a notable characteristic of the Node of Ranvier?

Answer 15

Answer: It has a very high density of Na+ channels.

Question 16

Question: What is the term for the innervation associated with the thoracolumbar region?

Answer 16

Answer: Sympathetic innervation

Question 17

Question: What is the term for the innervation associated with the craniosacral region?

Answer 17

Answer: Parasympathetic innervation.

Question 18

Question: What neurotransmitter is involved in effecting responses in the sympathetic division, and what receptors does it act on?

Answer 18

Answer: Noradrenaline (NA) acts on adrenoceptors in the sympathetic division.

Question 19

Question: What neurotransmitter is involved in effecting responses in the parasympathetic division, and what receptors does it act on?

Answer 19

Answer: Acetylcholine (Ach) acts on muscarinic Ach receptors in the parasympathetic division.

Question 20

Question: What neurotransmitter is common for both sympathetic and parasympathetic ganglia, and what receptors does it act on?

Answer 20

Answer: Acetylcholine (Ach) acts on nicotinic Ach receptors in both sympathetic and parasympathetic ganglia.

Question 21

Question: Where are the ganglia located in the sympathetic division?

Answer 21

Answer: Close to the spinal cord.

Question 22

Question: Where are the ganglia located in the parasympathetic division?

Answer 22

Answer: Close or within target organs.

Question 23

Question: What type of medicine is Hyoscine, and what is its primary use?

Answer 23

Answer: Hyoscine is an over-the-counter muscarinic antagonist used to treat abdominal cramps.

Question 24

Question: What type of medicine is Bethanechol, and for what condition is it prescribed?

Answer 24

Bethanechol is a prescribed muscarinic agonist used to treat urinary retention.

Question 25

Question: In a GP ileum preparation, what would be the effect of using Bethanechol?

Answer 25

Bethanechol, being a muscarinic agonist, would likely induce contraction or increased activity in the GP ileum preparation.

Question 26

Question: What is the primary function of the myenteric plexus?

Answer 26

Answer: The myenteric plexus is largely motor in function.

Question 27

Question: What is the primary function of the submucosal plexus?

Answer 27

Answer: The submucosal plexus is largely sensory in function.

Question 28

Question: How are nerve plexuses linked to the CNS, and what activates afferent fibers?

Answer 28

Answer: Nerve plexuses are linked to the CNS via afferent fibers activated by stretch and chemical stimulation.

Question 29

Question: What stimulates gut motility and secretory activity in the Enteric Nervous System (ENS)?

Answer 29

Answer: Parasympathetic (PS) input stimulates gut motility and secretory activity.

Question 30

Question: How do sympathetic nerves influence gut contraction induced by the parasympathetic system?

Answer 30

Answer: Sympathetic nerves cause presynaptic inhibition of parasympathetic-induced contraction.

Question 31

Question: Give an example of certain over-the-counter (OTC) medicines that modulate ENS function and GIT transit times.

Answer 31

Answer: Opioids are an example of OTC medicines that modulate Enteric Nervous System (ENS) function and GIT transit times.

Question 32

Question: Name the four main cell types found in the brain.

Answer 32

Answer: Neurons, astrocytes, microglia, oligodendrocytes.

Question 33

• Question: List some functions associated with the brain.

Answer 33

Answer: Consciousness, behavior, learning & memory, senses, voluntary & involuntary control of bodily functions.

Question 34

Question: What cell types are found in the spinal cord, and what is its primary function?

Answer 34

Answer: The spinal cord has similar cell types (neurons, astrocytes, microglia, oligodendrocytes) and serves as a pathway connecting the brain to the peripheral nervous system (PNS) and vice versa.

Question 35

Question: What are the components of the spinal cord involved in receiving peripheral afferent input?

Answer 35

Answer: The dorsal horn of the spinal cord receives peripheral afferent input.

Question 36

Question: Where does the efferent input originate in the spinal cord?

Answer 36

Answer: Efferent input originates from the ventral horn of the spinal cord.

Question 37

Question: How many vertebrae are present in the spinal column?

Answer 37

Answer: The spinal column has 31 vertebrae.

Question 38

Question: What types of innervation are associated with the spinal column?

Answer 38

Answer: Sympathetic innervation is linked to the thoracolumbar region, while parasympathetic innervation is linked to the craniosacral region.

Question 39

Question: What types of spinal tracts are involved in transmitting signals up and down the spinal cord?

Answer 39

Answer: Ascending spinal tracts transmit signals up, while descending spinal tracts transmit signals down the spinal cord.