Which of the following statements is true of dementia?

Correct Answer: B

Rationale: Dementia is an umbrella term for a group of conditions characterized by a decline in cognitive function, including memory loss, impaired reasoning, and changes in behavior. Alzheimer's disease is the most common form of dementia, but other types include vascular dementia and Lewy body dementia.

Correct Answer: C

Rationale: The correct sequence is afferent arteriole, glomerulus, efferent arteriole, and peritubular capillaries. Blood enters the nephron through the afferent arteriole, is filtered in the glomerulus, exits through the efferent arteriole, and then flows into the peritubular capillaries, where reabsorption and secretion occur. This pathway ensures efficient filtration and processing of blood in the kidneys.

Correct Answer: B

Rationale: Spasticity is the correct answer because upper motor neuron lesions typically result in increased muscle tone due to the loss of inhibitory signals from the brain. This leads to hyperreflexia, clonus, and rigidity, which are hallmark signs of spasticity. The condition arises from damage to the corticospinal tract, which disrupts the balance of excitatory and inhibitory inputs to the motor neurons.

Correct Answer: A

Rationale: Bulbar palsy is the correct answer because it results from damage to the lower motor neurons of the cranial nerves IX, X, and XII, which are located in the medulla oblongata. This condition leads to dysphagia, dysarthria, and tongue atrophy due to the loss of motor control in the muscles of the pharynx, larynx, and tongue.

Correct Answer: C

Rationale: Cerebellar is the correct answer because dysdiadochokinesis, or the inability to perform rapid alternating movements, is a hallmark sign of cerebellar dysfunction. The cerebellum is responsible for coordinating voluntary movements, and damage to this area disrupts the timing and precision of motor actions.