Schizophrenia and Parkinson's disease are both linked to changes in which neurotransmitter?

Correct Answer: C

Rationale: Dopamine is a neurotransmitter that plays a critical role in regulating mood, motivation, and movement. Schizophrenia is associated with excessive dopamine activity in certain brain regions, leading to symptoms like hallucinations and delusions. In contrast, Parkinson's disease is linked to a deficiency of dopamine in the basal ganglia, resulting in motor symptoms such as tremors and rigidity. Both conditions highlight the importance of dopamine in brain function and the consequences of its dysregulation.

Correct Answer: C

Rationale: Anterograde memory dysfunction is characterized by the inability to form new memories after a traumatic event or injury, as depicted in the film 'Memento.' This condition is often linked to damage in the hippocampus or surrounding medial temporal lobe structures, which are essential for encoding and storing new information. Individuals with this dysfunction can recall past memories but struggle to create new ones, leading to significant challenges in daily functioning.

Correct Answer: A

Rationale: Encephalitis is an inflammation of the brain typically caused by viral infections. Common symptoms include fever, headache, confusion, seizures, and cognitive impairments. While irritability can occur, it is not as specific or common as other symptoms like seizures or delirium. Encephalitis can lead to severe neurological complications if not treated promptly, making early diagnosis and intervention critical.

Correct Answer: B

Rationale: Neurons are the basic building blocks of the nervous system and consist of three main parts: dendrites, axons, and the cell body. Dendrites receive signals from other neurons, the cell body contains the nucleus and organelles, and the axon transmits signals to other neurons or target cells. These components work together to facilitate communication within the nervous system, enabling sensory perception, motor control, and cognitive functions.

Correct Answer: A

Rationale: The action potential pattern observed on an oscilloscope is caused by rapid changes in membrane polarity. During an action potential, the membrane potential depolarizes (becomes more positive) as sodium ions rush into the neuron, followed by repolarization (returning to negative) as potassium ions exit. These polarity changes are essential for the propagation of nerve impulses and are a hallmark of neural activity.