1.
Gaps between the myelin sheath along an axon are called:
Correct Answer
A. Nodes of Ranvier
Explanation
Gaps between the myelin sheath along an axon are called Nodes of Ranvier. These nodes are crucial for the conduction of nerve impulses. They allow the electrical signals to jump from one node to another, which speeds up the transmission of information along the axon. The myelin sheath acts as an insulating layer, and the nodes of Ranvier are the exposed areas where the axon membrane is not covered. This allows for the efficient propagation of the electrical impulses along the axon.
2.
The chemical that moves from the axon of one neuron across the synaptic gap to the dendrite of another neuron is called a:
Correct Answer
C. Neurotransmitter
Explanation
A neurotransmitter is a chemical that is released by a neuron and travels across the synaptic gap to bind to receptors on the dendrite of another neuron. This allows for the transmission of signals between neurons in the nervous system. Enzymes are not responsible for this process, as they typically facilitate chemical reactions rather than transmission of signals. Receptors are the proteins on the receiving neuron that bind to neurotransmitters. Transporter proteins are involved in the reuptake of neurotransmitters back into the neuron that released them, but they do not directly move the neurotransmitter across the synaptic gap.
3.
Which of the following is a function of the myelin sheath?
Correct Answer
B. Increases the speed at which nerve impulses travel along an axon
Explanation
The myelin sheath is a protective covering that surrounds nerve fibers. Its main function is to insulate and increase the speed of nerve impulses as they travel along an axon. This is achieved by preventing the leakage of electrical signals and allowing the impulses to jump from one node of Ranvier to another, a process known as saltatory conduction. This efficient transmission of nerve impulses helps to ensure fast and accurate communication between neurons, enabling rapid responses in the body.
4.
Part of the neuron that releases neurotransmitters into the synaptic cleft.
Correct Answer
D. Axon terminal
Explanation
The axon terminal is the part of the neuron that releases neurotransmitters into the synaptic cleft. Neurotransmitters are chemical messengers that transmit signals between neurons. The axon terminal is located at the end of the axon, which is the long fiber that extends from the cell body of the neuron. When an action potential reaches the axon terminal, it triggers the release of neurotransmitters into the synaptic cleft, where they can bind to receptors on the dendrites of the neighboring neurons, allowing for communication between neurons.
5.
A disease that destroys the protective and insulating myelin covering the neurons in a process called demyelination.
Correct Answer
A. Multiple Sclerosis
Explanation
Multiple Sclerosis is the correct answer because it is a disease that causes the destruction of the protective and insulating myelin covering the neurons, leading to demyelination. ALS, Progressive Bulbar Palsy, and Primary Lateral Sclerosis are not associated with the specific process of demyelination.
6.
Neurotransmitters are stored in:
Correct Answer
C. Synaptic vesicles
Explanation
Neurotransmitters are chemicals that transmit signals between neurons. They are stored in synaptic vesicles, which are small sacs located within the axon terminal of the presynaptic neuron. When an action potential reaches the axon terminal, these vesicles release the neurotransmitters into the synaptic cleft, the small gap between the presynaptic and postsynaptic neurons. From there, the neurotransmitters bind to receptors on the postsynaptic neuron, allowing for the transmission of the signal. Therefore, the correct answer is synaptic vesicles.
7.
When neurotransmitters are released into the synaptic cleft they bind to:
Correct Answer
B. The post-synaptic neuron receptor sites
Explanation
When neurotransmitters are released into the synaptic cleft, they bind to the post-synaptic neuron receptor sites. This is because these receptor sites are specifically designed to receive and respond to neurotransmitters. By binding to these receptor sites, neurotransmitters can transmit signals from the pre-synaptic neuron to the post-synaptic neuron, allowing for communication between neurons. The binding of neurotransmitters to post-synaptic receptor sites can lead to various effects, such as the opening of ion channels or the activation of intracellular signaling pathways.
8.
How does inactivation of neurotransmitters occur?
Correct Answer
A. Neurotransmitters are degraded by being broken down by enzymes or reused by active re-uptake.
Explanation
Neurotransmitters are degraded by being broken down by enzymes or reused by active re-uptake. This process allows for the efficient removal and recycling of neurotransmitters after they have transmitted their signals across the synapse. Enzymes break down the neurotransmitters into smaller molecules, while active re-uptake involves the reabsorption of neurotransmitters by the presynaptic neuron for future use. This inactivation process helps regulate the levels of neurotransmitters in the synaptic cleft and ensures proper neurotransmission.
9.
Some medications for the treatment of Schizophrenia block Dopamine receptors. What does that indicate about the role of Dopamine in Schizophrenia?
Correct Answer
D. There is too much Dopamine in the brains of SchizopHrenic people. Drugs that block Dopamine receptors will decrease the action of Dopamine.
Explanation
The fact that medications for the treatment of Schizophrenia block Dopamine receptors indicates that there is too much Dopamine in the brains of Schizophrenic people. By blocking the receptors, these medications decrease the action of Dopamine, which helps to alleviate the symptoms of Schizophrenia.
10.
If a medication inhibits the re-uptake of a neurotransmitter, what does that mean?
Correct Answer
B. It means that it will increase the level of the neurotransmitter available in the synaptic cleft and therefore increase its action.
Explanation
If a medication inhibits the re-uptake of a neurotransmitter, it means that it will increase the level of the neurotransmitter available in the synaptic cleft and therefore increase its action. Re-uptake is the process by which neurotransmitters are taken back up into the presynaptic neuron after they have been released into the synaptic cleft. By inhibiting this process, the medication allows more neurotransmitter to remain in the synaptic cleft, leading to increased stimulation of the postsynaptic neuron and enhancing the neurotransmitter's effects.
11.
Depression, suicide, impulsive behavior, and aggressiveness all appear to involve certain imbalances in:
Correct Answer
A. Serotonin
Explanation
Depression, suicide, impulsive behavior, and aggressiveness are all associated with imbalances in serotonin. Serotonin is a neurotransmitter that plays a crucial role in regulating mood, sleep, appetite, and behavior. Low levels of serotonin have been linked to depression and increased risk of suicide. Imbalances in serotonin can also lead to impulsive behavior and aggression. Therefore, it is likely that these mental health issues involve certain imbalances in serotonin.
12.
The loss of this neurotransmitter in certain parts of the brain causes the muscle rigidity typical of Parkinson’s disease.
Correct Answer
C. Dopamine
Explanation
Dopamine is the correct answer because the loss of this neurotransmitter in certain parts of the brain is known to cause the muscle rigidity that is characteristic of Parkinson's disease. Dopamine is involved in the regulation of movement and its deficiency in the brain leads to the motor symptoms associated with Parkinson's disease, such as muscle stiffness and rigidity.
13.
This substance delivers a sedative punch once it goes into the brain. It interacts with GABA receptors and drives them to be more inhibitory.
Correct Answer
B. Alcohol
Explanation
Alcohol is the correct answer because it is a substance that can deliver a sedative effect on the brain. It interacts with GABA receptors, which are responsible for inhibitory signals in the brain, and enhances their inhibitory activity. This leads to a decrease in brain activity and can result in sedation.
14.
This substance binds to Serotonin receptors but not always in the same way. This substance can inhibit or excite these receptors. This is why it has complex sensory effects.
Correct Answer
A. LSD
Explanation
LSD is the correct answer because it is a substance that binds to serotonin receptors but not always in the same way. It can either inhibit or excite these receptors, leading to its complex sensory effects.
15.
This substance binds to the opiate receptors. This mechanism turns off Dopamine inhibition and Dopamine gets released into the synapse. This generates feelings of sedation.
Correct Answer
D. Heroin
Explanation
Heroin is the correct answer because it is a substance that binds to the opiate receptors in the brain. This binding action turns off the inhibition of dopamine, a neurotransmitter responsible for feelings of pleasure and reward. As a result, dopamine is released into the synapse, leading to feelings of sedation and euphoria.