Histology Testbank: Lymphatic System 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.
What is a characteristic of a secondary nodule?
a. Germinal center
b. Lymphocytes
c. Capsule
d. Trabeculae
e. None of the above

Answer: a

A secondary lymphatic nodule is characterized by the presence of a germinal center.

2.
Which of the following is composed of epithelioreticular cells?
a. Spleen
b. Thymus
c. Bone marrow
d. Lymph node
e. None of the above

Answer: b

Bone marrow, lymph nodes, the spleen and the thymus are all part of the lymphatic system. Most lymphatic organs are made of a framework of reticular fibers and reticular cells. However, the thymus is made of epithelioreticular cells instead.

3.
What is the acronym for the diffuse lymphatic tissue in the respiratory tract?
a. BALT
b. DALT
c. FALT
d. GALT
e. HALT

Answer: a

Diffuse lymphatic tissue is non-encapsulated lymphatic tissue. It is found in the gastrointestinal tract, the genito-urinary tract, and the respiratory tract. In the gastrointestinal tract it is referred to as GALT (gut associated lymphatic tissue). In the respiratory tract it is referred to as BALT (bronchi associated lymphatic tissue).

4.
What are the localized concentrations of lymphocytes that are seen in the respiratory tract, genitourinary tract, and gastrointestinal tract?
a. Lymph follicles
b. White pulp
c. Peyer's patches
d. Lymph node
e. Diffuse lymphatic tissue

Answer: a

The localized concentrations of lymphocytes that are seen in the respiratory tract, genitourinary tract, and gastrointestinal tract are lymph follicles. They are also called lymphatic nodules.

The lymphatic tissue in the spleen is called white pulp.

The large aggregates of lymphatic tissue in the ileum are called Peyer's patches.

A lymph node is an encapsulated lymphatic organ.

The random distribution of lymphocytes seen in the lamina propria of the respiratory tract, genitourinary tract, and gastrointestinal tract is called diffuse lymphatic tissue. Difuse lymphatic tissue in not encapsulated.

5.
What is the lymphatic tissue in the spleen called?
a. Lymph follicles
b. White pulp
c. Peyer's patches
d. Lymph node
e. Diffuse lymphatic tissue

Answer: b

The localized concentrations of lymphocytes that are seen in the respiratory tract, genitourinary tract, and gastrointestinal tract are lymph follicles. They are also called lymphatic nodules.

The lymphatic tissue in the spleen is called white pulp.

The large aggregates of lymphatic tissue in the ileum are called Peyer's patches.

A lymph node is an encapsulated lymphatic organ.

The random distribution of lymphocytes seen in the lamina propria of the respiratory tract, genitourinary tract, and gastrointestinal tract is called diffuse lymphatic tissue. Difuse lymphatic tissue in not encapsulated.

6.
What are the splenic cords?
a. Cords of Billroth
b. Cords of Paneth
c. Cords of Bellini
d. Cords of Rothchild
e. Cords of Hassall

Answer: a

The splenic cords are also called the cords of Billroth.

7.
When looking at the spleen, what are the invaginations of the capsule into the splenic parenchyma called?
a. Malpighian corpuscle
b. Trabeculae
c. White pulp
d. Red pulp
e. Cords of Billroth

Answer: b

The spleen has a connective tissue capsule. The invaginations of the capsule into the splenic parenchyma are trabeculae.

The parenchyma of the spleen can be divided into the white pulp and the red pulp. The white pulp of the spleen is the lymphatic portion of the spleen. Within the white pulp, splenic nodules are found. Splenic nodules are also called Malpighian corpuscles.

The red pulp is made up of the splenic sinuses and splenic cords. The splenic cords are also called the cords of Billroth.

8.
When looking at a lymph node, which term does not refer to the same region as all the others listed?
a. Deep cortex
b. Tertiary cortex
c. Outer cortex
d. Juxtamedullary cortex
e. Paracortical zone

Answer: c

Deep cortex, tertiary cortex, juxtamedullary cortex and paracortical zone are all terms for the same region in a lymph node. The deep cortex is the inner region of the cortex, next to the medulla.

9.
What are the spherical structures seen in the medulla of the thymus called?
a. Psammoma bodies
b. Corpora arenacea
c. Hassall's corpuscles
d. Prostatic concretions
e. Pacinian corpuscles

Answer: c

Psammoma bodies are collections of calcium. It is derived from the Greek word "psammos", which means sand.

Corpora arenacea refers to the calcifications seen in the pineal gland. Corpora arenacea is nicknamed "brain sand".

Hassall's corpuscles are the ring like structures found in the thymus.

The spherical structures seen in some prostatic alveoli are called prostatic concretions.

Pacinian corpuscles are pressure receptors in the skin.

10.
Where are Peyer's patches located?
a. Esophagus
b. Stomach
c. Small intestine
d. Large intestine
e. Rectum

Answer: c

Peyer's patches are large nodules of lymphatic tissue. They are seen in the small intestine.