Bone Marrow

Study Questions

Question 1
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Tab 3

A 28-year-old woman is found to have pulmonary sarcoidosis. Flow cytometric analysis of T cells isolated from the alveoli and lung interstitium reveals the presence of large numbers of T helper (TH1) cells. These cells are known to secrete which of the following substances?

A. Complement component C5A
B. Elastase and lysyl hydroxylase
C. IL-2 and interferon-γ
D. IL-8 and transforming growth factor β
E. Leukotrienes C4 and C5

Answer

Content 2

Content 3

Question 2 of 10

Which of the following is not true of the bone marrow?

It serves as the major source of formed blood elements after birth.

In patients who are suspected of having metastatic carcinoma, examination of the marrow may be useful in establishing a tissue diagnosis.

It is often examined to determine the cause of pancytopenia.

It is the primary site of hematopoiesis during embryonic development.

It contains fat cells that may negatively regulate hematopoiesis.

It contains a niche that nurtures stem cells.

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The correct answer is D. You answered D.

Explanation:

During embryonic development, the primary sites of hematopoiesis are the yolk sac, the mesonephros, and the liver. (The answer is D.)

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