MCAT Problem of the Day: 1001

Question:

A patient with a history of hypertension and hyperlipidemia presents with chest pain. Physical examination reveals normal vital signs, no murmurs, and no carotid bruits. Electrocardiogram shows ST segment elevation in leads V1-V3. Which of the following is the most likely diagnosis?

(A) Aortic dissection
(B) Myocardial infarction
(C) Pericarditis
(D) Pulmonary embolism

Answer:

(B) Myocardial infarction

Explanation:

The patient's symptoms and electrocardiogram findings are most consistent with myocardial infarction. The patient has a history of hypertension and hyperlipidemia, both of which are risk factors for coronary artery disease. The chest pain and ST segment elevation in leads V1-V3 are classic signs of myocardial infarction.

MCAT Problem of the Day: 1002

Question:

Which of the following is NOT a mechanism of action of aspirin?

(A) Inhibition of platelet aggregation
(B) Inhibition of cyclooxygenase-1 (COX-1)
(C) Inhibition of cyclooxygenase-2 (COX-2)
(D) Vasodilation

Answer:

(C) Inhibition of cyclooxygenase-2 (COX-2)

Explanation:

Aspirin is a nonsteroidal anti-inflammatory drug (NSAID) that works by inhibiting the production of prostaglandins. Prostaglandins are produced by the enzyme cyclooxygenase (COX). Aspirin irreversibly inhibits COX-1, which is found in platelets and is responsible for platelet aggregation. Aspirin also inhibits COX-2, which is found in the body's tissues and is responsible for inflammation. However, the inhibition of COX-2 by aspirin is reversible.

MCAT Problem of the Day: 1003

Question:

Which of the following is a common cause of secondary hyperthyroidism?

(A) Graves' disease
(B) Hashimoto's thyroiditis
(C) Pituitary adenoma
(D) Thyroiditis

Answer:

(C) Pituitary adenoma

Explanation:

Secondary hyperthyroidism is caused by excessive production of thyroid-stimulating hormone (TSH) by the pituitary gland. The most common cause of secondary hyperthyroidism is a pituitary adenoma, which is a benign tumor of the pituitary gland. The pituitary adenoma produces excessive amounts of TSH, which stimulates the thyroid gland to produce excessive amounts of thyroid hormone.

MCAT Problem of the Day: 1004

Question:

Which of the following is a risk factor for developing type 2 diabetes?

(A) Obesity
(B) Physical inactivity
(C) Family history of type 2 diabetes
(D) All of the above

Answer:

(D) All of the above

Explanation:

Obesity, physical inactivity, and family history of type 2 diabetes are all risk factors for developing type 2 diabetes. Obesity is the strongest risk factor, followed by physical inactivity. Family history of type 2 diabetes also increases the risk of developing the disease.

MCAT Problem of the Day: 1005

Question:

Which of the following is NOT a symptom of iron deficiency anemia?

(A) Fatigue
(B) Weakness
(C) Palpitations
(D) Jaundice

Answer:

(D) Jaundice

Explanation:

Iron deficiency anemia is a condition in which the body does not have enough iron to produce red blood cells. Symptoms of iron deficiency anemia include fatigue, weakness, and palpitations. Jaundice is not a symptom of iron deficiency anemia. Jaundice is a condition in which the skin and whites of the eyes turn yellow. It is caused by a buildup of bilirubin in the body.

MCAT Problem of the Day: 1006

Question:

Which of the following is a treatment for hyperthyroidism?

(A) Radioactive iodine
(B) Antithyroid drugs
(C) Surgery
(D) All of the above

Answer:

(D) All of the above

Explanation:

Hyperthyroidism is a condition in which the body produces too much thyroid hormone. Treatments for hyperthyroidism include radioactive iodine, antithyroid drugs, and surgery. Radioactive iodine is a radioactive substance that is taken orally and destroys thyroid tissue. Antithyroid drugs are medications that block the production of thyroid hormone. Surgery is an option for patients who do not respond to radioactive iodine or antithyroid drugs.

MCAT Problem of the Day: 1007

Question:

Which of the following is a symptom of hypothyroidism?

(A) Fatigue
(B) Weight gain
(C) Cold intolerance
(D) All of the above

Answer:

(D) All of the above

Explanation:

Hypothyroidism is a condition in which the body does not produce enough thyroid hormone. Symptoms of hypothyroidism include fatigue, weight gain, and cold intolerance. Fatigue is the most common symptom of hypothyroidism. Weight gain is also common, as is cold intolerance.

MCAT Problem of the Day: 1008

Question:

Which of the following is a risk factor for