LESSON 2a: NEURONS AND SYNAPSES

True. There are approximately 25 human senses.

46. True or False: There are approximately 25 human senses.

Answer: b) Depolarize the post-synaptic potential

10. What do excitatory neurotransmitters do? a) Hyperpolarize the post-synaptic potential b) Depolarize the post-synaptic potential c) Modulate/regulate the action potential transmitted d) None of the above

Answer: c) The meeting point between two neurons

1. What is a synapse? a) A type of neurotransmitter b) A neuron that carries information into the central nervous system c) The meeting point between two neurons d) A type of neuron that is contained within the central nervous system

Answer: a) Hyperpolarize the post-synaptic potential

11. What do inhibitory neurotransmitters do? a) Hyperpolarize the post-synaptic potential b) Depolarize the post-synaptic potential c) Modulate/regulate the action potential transmitted d) None of the above

Answer: c) The sum of all the excitations and inhibitions in that area

12. What is the likelihood of the post-synaptic neuron developing an action potential based on? a) The sum of all the excitations in that area b) The sum of all the inhibitions in that area c) The sum of all the excitations and inhibitions in that area d) None of the above

Answer: c) About 25

13. How many human senses are there? a) About 10 b) About 15 c) About 25 d) About 50

Answer: d) Growth

14. Which of the following is not a human sense? a) Sight b) Hearing c) Pain d) Growth

a) Acetylcholine b) Serotonin c) Nucleotide d) Dopamine Answer: c) Nucleotide

15. Which of the following is NOT a type of neurotransmitter?

Answer: a) GABA

16. Which of the following is a type of neurotransmitter that is inhibitory in nature? a) GABA b) Dopamine c) Serotonin d) Acetylcholine

Answer: c) They hyperpolarize the post-synaptic neuron

17. Which of the following is true about the function of inhibitory neurotransmitters? a) They depolarize the post-synaptic neuron b) They bring the neuron closer to the threshold c) They hyperpolarize the post-synaptic neuron d) They modulate and regulate the action potential transmitted

Answer: b) Chemical synapse

18. Which of the following types of synapses is slower and selective, and uses neurotransmitters to propagate the signal? a) Electrical synapse b) Chemical synapse c) Motor synapse d) Sensory synapse

True. Acetylcholine has an important role in muscle contraction, stimulating skeletal muscle contraction at neuromuscular junctions and inhibiting cardiac muscle contraction.

19. True or False: Acetylcholine has an important role in muscle contraction.

Answer: b) They have gap junctions that allow for the passage of ions

2. What is the function of an electrical synapse? a) They are abundant, controlled, slower, selective, one-way transmission b) They have gap junctions that allow for the passage of ions c) They use neurotransmitters diffused across the synaptic gap and receptors to propagate the signal d) They are common in smooth and cardiac muscle

Answer: d) Interneuron

20. Which of the following is NOT a type of neuron based on structure? a) Unipolar neuron b) Bipolar neuron c) Multipolar neuron d) Interneuron

Answer: c) Pseudounipolar neuron

21. Which of the following types of neurons has only one process and is found in touch and pain sensory neurons? a) Bipolar neuron b) Multipolar neuron c) Pseudounipolar neuron d) Interneuron

Answer: b) Interneuron

22. Which of the following types of neurons is contained within the central nervous system? a) Sensory neuron b) Interneuron c) Motor neuron d) Pseudounipolar neuron

Answer: c) Glycine

23. Which of the following types of neurotransmitters is an amino acid that is inhibitory in nature? a) Glutamate b) Aspartate c) Glycine d) Dopamine

Answer: d) They depolarize the post-synaptic neuron

24. Which of the following is true about the function of excitatory neurotransmitters? a) They hyperpolarize the post-synaptic neuron b) They inhibit the generation of action potential c) They modulate and regulate the action potential transmitted d) They depolarize the post-synaptic neuron

Answer: a) Electrical synapse

25. Which of the following types of synapses is immediate and fast, and allows for the passage of ions through gap junctions? a) Electrical synapse b) Chemical synapse c) Motor synapse d) Sensory synapse

Answer: c) Multipolar neuron

26. Which of the following types of neurons has more than two processes and is found in motor neurons and pyramidal neurons? a) Unipolar neuron b) Bipolar neuron c) Multipolar neuron d) Pseudounipolar neuron

Answer: c) Serotonin

27. Which of the following types of neurotransmitters is synthesized from tryptophan? a) Glutamate b) Aspartate c) Serotonin d) GABA

Answer: b) Acetylcholine

28. Which of the following types of neurotransmitters is a choline molecule that has been acetylated? a) Glutamate b) Acetylcholine c) Norepinephrine d) Serotonin

Answer: b) Hyperpolarize the post-synaptic neuron and c) Modulate/regulate the action potential

29. What is the function of inhibitory neurotransmitters? a) Depolarize the post-synaptic neuron b) Hyperpolarize the post-synaptic neuron c) Modulate/regulate the action potential d) Allow the propagation of the signal

Answer: a) Chemical and electrical

3. What are the two types of synapses? a) Chemical and electrical b) Sensory and motor c) Inhibitory and excitatory d) None of the above

Answer: a) Unipolar neuron

30. Which type of neuron has a single process and is responsible for touch and pain sensation? a) Unipolar neuron b) Bipolar neuron c) Multipolar neuron d) Pseudounipolar neuron

Answer: b) Interneuron

31. Which type of neuron is contained within the central nervous system (CNS)? a) Sensory neuron b) Interneuron c) Motor neuron d) Pseudounipolar neuron

Answer: c) Motor neuron

32. Which type of neuron carries information out of the CNS? a) Sensory neuron b) Interneuron c) Motor neuron d) Pseudounipolar neuron

Answer: c) Glutamate

33. Which neurotransmitter is excitatory? a) Glycine b) GABA c) Glutamate d) Histamine

Answer: a) It triggers ligand-gated channels to open and allow positively charged ions into the cell, making it more positive and less polarized, allowing the generation of action potential.

34. What happens when glutamate neurotransmitter binds to the glutamate receptor? a) It triggers ligand-gated channels to open and allow positively charged ions into the cell, making it more positive and less polarized, allowing the generation of action potential. b) It triggers ligand-gated channels to open and allow negatively charged ions into the cell, making it more negative and more polarized, inhibiting the generation of action potential. c) It inhibits muscle contraction. d) It stimulates muscle contraction.

Answer: b) It triggers ligand-gated channels to open and allow negatively charged ions (chloride) into the cell, making it more negative and more polarized, inhibiting the generation of action potential.

35. What happens when GABA neurotransmitter binds to the GABA receptor? a) It triggers ligand-gated channels to open and allow positively charged ions into the cell, making it more positive and less polarized, allowing the generation of action potential. b) It triggers ligand-gated channels to open and allow negatively charged ions (chloride) into the cell, making it more negative and more polarized, inhibiting the generation of action potential. c) It inhibits muscle contraction. d) It stimulates muscle contraction.

Answer: c) Acetylcholine

36. Which type of neurotransmitter has an important role in muscle contraction? a) Amino acids b) Monoamines c) Acetylcholine d) Neuropeptides

True. A synapse is the point where two neurons meet and means "to clasp or join."

37. True or False: A synapse is the point where two neurons meet and means "to clasp or join."

False. Electrical synapses are immediate, fast, and coordinated. They have gap junctions that allow for the passage of ions and are common in smooth and cardiac muscle.

38. True or False: Electrical synapses are abundant, controlled, and slower.

True. Chemical synapses are abundant, controlled, slower, selective, one-way transmissions, and use neurotransmitters diffused across the synaptic gap and receptors to propagate the signal.

39. True or False: Chemical synapses are selective, one-way transmissions, and use neurotransmitters diffused across the synaptic gap and receptors to propagate the signal.

Answer: a) Immediate and fast

4. What type of transmission occurs in electrical synapses? a) Immediate and fast b) Abundant and controlled c) Selective and one-way d) Slower and coordinated

True. Potentiation is the strengthening of a synapse through classic conditioning.

40. True or False: Potentiation is the strengthening of a synapse through classic conditioning.

False. Habituation is the decreasing response of a synapse to a common stimulus.

41. True or False: Habituation is the increasing response of a synapse to a common stimulus.

True. Sensitization is the reaction to one stimulus that causes other synapses to be more sensitive to reactions.

42. True or False: Sensitization is the reaction to one stimulus that causes other synapses to be more sensitive to reactions.

False. Excitatory neurotransmitters depolarize the post-synaptic potentials, making the inside more positive, and pushing the neuron closer to the threshold, making an action potential more likely to occur.

43. True or False: Excitatory neurotransmitters depolarize the post-synaptic potentials, making the inside more negative, and bringing the neuron away from the threshold.

True. Inhibitory neurotransmitters hyperpolarize the post-synaptic potentials, making the inside more negative, and bringing the neuron away from the threshold.

44. True or False: Inhibitory neurotransmitters hyperpolarize the post-synaptic potentials, making the inside more negative, and bringing the neuron away from the threshold.

True. The likelihood of the post-synaptic neuron developing an action potential depends on the sum of all the excitations and inhibitions in that area.

45. True or False: The sum of all the excitations and inhibitions in an area determines the likelihood of the post-synaptic neuron developing an action potential.

False. Unipolar neurons have a single process. Examples of unipolar neurons include touch and pain sensory neurons.

47. True or False: Unipolar neurons have two processes.

False. Sensory neurons (unipolar and pseudounipolar) carry information into the central nervous system. Interneurons are contained within the central nervous system (CNS), while motor neurons (multipolar) carry information out of the CNS.

48. True or False: Interneurons carry information into the central nervous system.

False. Glutamate is an excitatory neurotransmitter that depolarizes the post-synaptic potentials, making the inside more positive and less polarized, allowing the generation of an action potential.

49. True or False: Glutamate is an inhibitory neurotransmitter.

Answer: b) Chemical

5. Which type of synapse uses neurotransmitters? a) Electrical b) Chemical c) Both electrical and chemical d) Neither electrical nor chemical

True. Some neuropeptides are involved in retrograde transmission, including substance P and dynorphin. Retrograde transmission is a process in which signals are transmitted from the postsynaptic neuron to the presynaptic neuron, and neuropeptides are known to play a role in this process. They can modulate the release of neurotransmitters by binding to receptors on the presynaptic terminal and triggering the release of signaling molecules that modify the activity of the presynaptic neuron.

50. True or False: Neuropeptides are involved in retrograde transmission.

Excitatory neurotransmitters depolarize the postsynaptic potentials, making the neuron more positive and closer to the threshold, increasing the likelihood of an action potential. Meanwhile, inhibitory neurotransmitters hyperpolarize the postsynaptic potentials, making the neuron more negative and away from the threshold, halting the signal transmission. Together, the balance of excitatory and inhibitory neurotransmitters regulates or modulates the action potential transmitted, which determines the likelihood of the postsynaptic neuron developing an action potential.

51. What are excitatory and inhibitory neurotransmitters? How do they modulate or regulate the action potential transmitted?

Based on structure, neurons can be classified into 5 types: unipolar, bipolar, multipolar, pseudounipolar, and anaxonic neurons. Unipolar and pseudounipolar neurons are sensory neurons that carry information into the central nervous system, while interneurons are contained within the central nervous system. Multipolar neurons, on the other hand, carry information out of the CNS and are motor neurons. Bipolar neurons have two processes and are responsible for sensory functions in the retina and olfactory systems. Lastly, anaxonic neurons have no axon and are primarily responsible for modulating or regulating the signals in the retina.

52. Enumerate the types of neurons based on structure and their corresponding functions.

Electrical synapse is a type of synapse where two neurons are connected by gap junctions, allowing ions to flow freely from one neuron to another, resulting in immediate and rapid two-way transmission. Meanwhile, chemical synapses use neurotransmitters to propagate signals, which are diffused across the synaptic gap and bind to receptors, resulting in a controlled, selective, and slower one-way transmission. One advantage of electrical synapse is its immediate and coordinated response; however, its drawback is that it cannot regulate or modulate the signal. In contrast, chemical synapse provides abundant control, making it selective and modifiable, but at the cost of slower transmission and high energy usage.

53. Differentiate electrical synapse from chemical synapse. Explain the advantages and disadvantages of each type of synapse.

Potentiation is the strengthening of a synapse through classical conditioning. For instance, a dog salivates when it hears a bell ringing because it has been conditioned to associate the bell with food, causing potentiation in the neural circuitry responsible for salivation. Habituation is a process in which the response of a synapse decreases over time to a common stimulus. For instance, one may not notice the background noise in a crowded room after some time, as the synapse responsible for detecting that sound is habituated. Sensitization is a phenomenon in which a reaction to one stimulus causes other synapses to be more sensitive to reactions. For example, after hearing a loud noise, a person might become more sensitive to other noises, causing them to startle more easily.

54. Explain the concept of potentiation, habituation, and sensitization, and provide examples of each.

Excitatory and inhibitory neurotransmitters are both organic chemical messengers that transmit signals between presynaptic and postsynaptic neurons. Excitatory neurotransmitters depolarize the post-synaptic potentials, making the inside of the neuron more positive and pushing the neuron closer to threshold, increasing the likelihood of an action potential occurring. On the other hand, inhibitory neurotransmitters hyperpolarize the post-synaptic potentials, making the inside of the neuron more negative and away from the threshold, halting the signal. While excitatory neurotransmitters depolarize the neuron to propagate the signal, inhibitory neurotransmitters act to modulate/regulate the action potential transmitted, sometimes allowing the sharpening of signals.

55. Compare and contrast the functions of excitatory and inhibitory neurotransmitters.

Acetylcholine is a choline molecule that has been acetylated and has an important role in muscle contraction. In neuromuscular junctions, acetylcholine stimulates skeletal muscle contraction, while in cardiac muscle, acetylcholine inhibits cardiac muscle contraction. Acetylcholine is also involved in regulating attention, arousal, and reward, and its deficiency is associated with Alzheimer's disease.

56. Explain the function of acetylcholine neurotransmitter and provide examples of its role in muscle contraction.

Answer: a) The strengthening of a synapse through classic conditioning

6. What is potentiation? a) The strengthening of a synapse through classic conditioning b) The decreasing response of a synapse to a common stimulus c) The reaction to one stimulus that causes other synapses to be more sensitive to reactions d) None of the above

Answer: b) The decreasing response of a synapse to a common stimulus

7. What is habituation? a) The strengthening of a synapse through classic conditioning b) The decreasing response of a synapse to a common stimulus c) The reaction to one stimulus that causes other synapses to be more sensitive to reactions d) None of the above

Answer: c) The reaction to one stimulus that causes other synapses to be more sensitive to reactions

8. What is sensitization? a) The strengthening of a synapse through classic conditioning b) The decreasing response of a synapse to a common stimulus c) The reaction to one stimulus that causes other synapses to be more sensitive to reactions d) None of the above

Answer: a) Inhibitory and excitatory

9. What are the two functions of neurotransmitters? a) Inhibitory and excitatory b) Chemical and electrical c) Sensory and motor d) None of the above