Instructions: because that each histology question, pick the one best answer. This histology test bank is additionally useful because that the histology inquiries on the USMLE (USMLE action 1).

1. Roughly what percent of the volume that blood perform the formed elements comprise? a. 5 b. 25 c. 45 d. 75 e. 90

Answer: c

Blood is created of the developed elements and plasma. Plasma is the liquid portion of blood. The formed aspects consist that the cells and cell fragments. The erythrocytes (red blood cells), platelets, and also leukocytes (white blood cells) room all considered formed elements.

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When a sample of blood is centrifuged, the percentage populated by the formed elements is the hematocrit. An mean hematocrit is around 45%.

2. I m sorry of the following is the most abundant in a peripheral smear that blood? a. Neutrophils b. Basophils c. Erythrocytes d. Leukocytes e. Platelets

Answer: c

Erythrocytes (red blood cells) space the many abundant formed element in a peripheral smear of blood.

3. I m sorry leukocyte is the least abundant in a peripheral smear that blood? a. Lymphocytes b. Basophils c. Neutrophil d. Monocytes e. Eosinophils

Answer: b

Basophils space the least abundant leukocyte.

Leukocytes are the white blood cells. The bespeak of frequency that the leukocytes is: neutrophil, lymphocyte, monocyte, eosinophil, basophil.

Histology hints from buy it Bellham: The bespeak of frequency the the leukocytes can be mental by the mnemonic: "Never Let primates Eat Bananas".

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4. Which of the complying with is not a granulocyte? a. PMN b. Basophils c. Neutrophil d. Monocytes e. Eosinophils

Answer: d

The granulocytes room named due to the fact that of the existence of clearly shows cytoplasmic granules. The granulocytes covers neutrophils, eosinophils, and basophils. "PMN" is an abbreviation because that polymorphonuclear neutrophil. Thus, the is a neutrophil, i beg your pardon is a granulocyte. The non-granulocytes space lymphocytes and also monocytes.

Histology hints from sarah Bellham: Poly is from the Greek "polys", which method many. "Poly" is additionally sometimes supplied as a nickname for polymorphonuclear leukocyte.

5. I m sorry of the adhering to is a granulocyte? a. Thrombocyte b. Monocyte c. Lymphocyte d. Basophil e. Erythrocyte

Answer: d

The granulocytes room named because of the existence of visible cytoplasmic granules. The granulocytes consists neutrophils, eosinophils, and basophils. The non-granulocytes are lymphocytes and monocytes. Erythrocytes are red blood cells. A thrombocyte is a platelet.

Histology note from sarah Bellham: The suffix (or prefix) "phil" originates from the Greek word definition love. It is supplied to clues an attraction or affinity towards something. It is seen in such words as philosophy, philanthropy and bibliophile.

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This suffix is provided in naming the 3 granulocytes: eosinophils, basophils, and also neutrophils. Eosinophils "love" or room attracted come the eosin dye; for this reason the granules in one eosinophil room orange/pink. Basophils "love" or room attracted come the basophilic dye; hence the granules in a basophil room blue. Neutrophils "love" or room attracted to the neutral dye; therefore the granules in a neutrophil room neutral colored.

6. I m sorry of the following is described as having a "central pallor"? a. Leukocytes b. Monocytes c. Eosinophils d. Platelets e. Erythrocytes

Answer: e

Erythrocytes (red blood cells) are explained as biconcave discs. When stained, this phenomenon results in the main portion of the cell staining lighter, therefore the "central pallor".

Histology hint from buy it Bellham: A biconcave disc have the right to be visualized by holding two Frisbees together so that the middle portion is thinner than the optimal or bottom.

7. Which is the smallest leukocyte? a. Neutrophil b. Lymphocytes c. Monocytes d. Eosinophil e. Basophils

Answer: b

The leukocytes consists neutrophils, lymphocytes, monocytes, eosinophils, and also basophils.

Neutrophils space granulocytes. Neutrophils have actually a multi-lobed nucleus. The lobes space separated through a thin strand. Since of the form of the nucleus, neutrophils are also called "polymorphonuclear neutrophils", "poly"s", "PMN", or "polymorph.

Lymphocytes are agranulocytes. Lymphocytes have the right to be categorized by three sizes: small, medium, and large. The little lymphocytes space the smallest leukocyte, being only slightly larger than an erythrocyte.

Monocytes are agranulocytes. They room the largest leukocyte.

Eosinophils space granulocytes. Eosinophils have actually prominent orange pink granules. The nucleus of eosinophils is generally bi-lobed.

Basophils room granulocytes. Basophils have big blue granules, which regularly obscure the nucleus. The granules room basophilic, therefore they are blue.

8. I m sorry leukocyte usually has a bi-lobed nucleus? a. Neutrophil b. Lymphocytes c. Monocytes d. Eosinophil e. Basophils

Answer: d

The leukocytes covers neutrophils, lymphocytes, monocytes, eosinophils, and also basophils.

Neutrophils room granulocytes. Neutrophils have a multi-lobed nucleus. The lobes are separated by a slim strand. Because of the shape of the nucleus, neutrophils are likewise called "polymorphonuclear neutrophils", "poly"s", "PMN", or "polymorph".

Lymphocytes are agranulocytes. Lymphocytes deserve to be categorized by three sizes: small, medium, and also large. The little lymphocytes are the smallest leukocyte, being just slightly bigger than one erythrocyte.

Monocytes are agranulocytes. They room the biggest leukocyte.

Eosinophils room granulocytes. Eosinophils have actually prominent orange pink granules. The nucleus of eosinophils is typically bi-lobed.

Basophils are granulocytes. Basophils have large blue granules, which frequently obscure the nucleus. The granules space basophilic, thus they are blue.

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9. What is the buffy coat? a. Leukocytes b. Platelets c. Erythrocytes d. Plasma e. Both a and b

Answer e:

The buffy cloak is seen in a sample of centrifuged blood. That is the slim layer over the red blood cells, but listed below the plasma. It is composed of the leukocytes and platelets.

10. What is another term because that a platelet? a. Thrombocyte b. Monocyte c. Lymphocyte d. Basophil e. Erythrocyte