Histology Testbank: Connective Tissue 2a

Instructions: For each histology question, pick the one best answer. This histology test bank is also useful for the histology questions on the USMLE (USMLE step 1).

1.
Which of the following is NOT primarily composed of connective tissue?
a. Bone marrow
b. Articular cartilage
c. Heart
d. Mesenchyme
e. Fat

Answer: c

Of the four basic tissue types (epithelium, connective tissue, muscle and nervous tissue), connective tissue is the most diverse. Bone marrow, articular cartilage, mesenchyme and fat are all composed of connective tissue. The heart is a muscle. The main tissue type in the heart is cardiac muscle.

Note from Sarah Bellham: Please be aware that there is connective tissue in the heart. The blood in the heart, for example, is composed of connective tissue. The pericardium is also composed of connective tissue. However, the primary tissue composing the heart is cardiac muscle.

2.
Which one of these cells is not a cell type routinely found in loose connective tissue?
a. Fibroblast
b. Microglia
c. Histiocyte
d. Plasma cell
e. Mast cell

Answer: b

Microglia are supporting cells in the nervous system.

Fibroblasts, histiocytes, plasma cells, and mast cells are routinely seen in loose connective tissue. Fibroblasts produce collagen. The fibroblast also produces the ground substance in connective tissue. The histiocyte is a tissue macrophage. Plasma cells are derived from B lymphocytes. Mast cells secrete histamine. Mast cells also secrete heparin, SRS-A (slow reacting substance of anaphylaxis, ECF-A (eosinophilic chemotactic factor of anaphylaxis.

3.
Which connective tissue cell is a tissue macrophage?
a. Fibroblast
b. Myofibroblast
c. Histiocyte
d. Plasma cell
e. Mast cell

Answer: c

The histiocyte is a tissue macrophage.

Fibroblasts, histiocytes, plasma cells, and mast cells are routinely seen in loose connective tissue. Fibroblasts produce collagen. The fibroblast also produces the ground substance in connective tissue. Myofibroblasts contain properties of both fibroblasts and smooth muscle cells. The histiocyte is a connective tissue macrophage. Plasma cells are derived from B lymphocytes. Mast cells secrete histamine. Mast cells also secrete heparin, SRS-A (slow reacting substance of anaphylaxis, ECF-A (eosinophilic chemotactic factor of anaphylaxis.

4.
Which of the following can be classified as "specialized connective tissue"?
a. Cartilage
b. Loose connective tissue
c. Mesenchyme
d. Dense connective tissue
e. Mucous connective tissue

Answer: a

Connective tissue can be sub-classified into connective tissue proper, specialized connective tissue and embryonic connective tissue.

Connective tissue proper consists of loose irregular connective tissue and dense connective tissue (regular and irregular).

Specialized connective tissue includes cartilage, bone, adipose tissue, blood and hemopoietic tissue, and lymphatic tissue.

Embryonic connective tissue includes mesenchyme and mucous connective tissue.

5.
Which of the following can be classified as "connective tissue proper"?
a. Adipose tissue
b. Dense irregular connective tissue
c. Bone
d. Blood
e. Cartilage

Answer: b

Connective tissue can be sub-classified into connective tissue proper, specialized connective tissue and embryonic connective tissue.

Connective tissue proper consists of loose irregular connective tissue and dense connective tissue (regular and irregular).

Specialized connective tissue includes cartilage, bone, adipose tissue, blood and hemopoietic tissue, and lymphatic tissue.

Embryonic connective tissue includes mesenchyme and mucous connective tissue.

6.
What type of tissue is Wharton's jelly?
a. Mucous connective tissue
b. Mesenchyme
c. Loose irregular connective tissue
d. Dense irregular connective tissue
e. Dense regular connective tissue

Answer: a

Mesenchyme is embryonic connective tissue. It is an undifferentiated tissue found in the embryo. Mucous connective tissue is a type of embryonic connective tissue; it is a subset of mesenchyme. Wharton's jelly is mucous connective tissue. Loose irregular connective tissue is areolar tissue. Dense irregular connective tissue is seen in the dermis. Dense regular connective tissue comprises tendons and ligaments.

7.
What type of tissue is a tendon composed of?
a. Mucous connective tissue
b. Mesenchyme
c. Loose irregular connective tissue
d. Dense irregular connective tissue
e. Dense regular connective tissue

Answer: e

Mesenchyme is embryonic connective tissue. It is an undifferentiated tissue found in the embryo. Mucous connective tissue is a type of embryonic connective tissue; it is a subset of mesenchyme. Wharton's jelly is mucous connective tissue. Loose irregular connective tissue is areolar tissue. Dense irregular connective tissue is seen in the dermis. Dense regular connective tissue comprises tendons and ligaments.

8.
What does connective tissue develop from?
a. Mesothelium
b. Mesenchyme
c. Mesangial cells
d. Mesentery
e. Wharton's jelly

Answer: b

Connective tissue develops from mesenchyme.

9.
What color do elastic fibers stain with Verhoeff Elastic stain?
a. Red/Orange
b. Pink/red
c. Purple/Red
d. Blue/black
e. Green/blue

Answer: d

Verhoeff Elastic stain stains elastic fibers blue/black. Collagen stains pink/red.

10.
Which of the following is a component of the ground substance?
a. Hyaluronic acid
b. Proteoglycans
c. Glycosaminoglycans
d. Chondroitin sulfate
e. All of the above

Answer: e

Within connective tissue, the cells and fibers are embedded in the ground substance. The ground substance is amorphous material. It is composed of proteoglycans and glycosaminoglycans. Hyaluronic acid and chondroitin sulfate are glycosaminoglycans.