The respiratory system

Question 1

From the upper nasal cavity to the bronchioles the respiratory tract is lined with a specialized mucosa, what is it called? Describe the cell layer and its functions.

Answer 1

Respiratory epithelium that functions to filter, warm and moisten the air. This cell layer is composed of a ciliated pseudo stratified columnar epithelium interspersed with goblet cells. (It has 5 cell types in all)

Question 2

What is Kartagener syndrome and what are its side-effects?

Answer 2

A genetic disorder in which the protein dynein is not functional or absent. Dynein is critical to cilia beating. These individuals often suffer from frequent respiratory infections since they lack the function of the much-ciliary elevator.

Question 3

Which are deeper in the respiratory tract, cilia or goblet cells?

Answer 3

Cilia this is to prevent retrograde flow of mucous.

Question 4

What are cell types are the inferior, middle and superior conchae lined with?

Answer 4

Inferior and middle - respiratory epithelium.
Superior - olfactory epithelium.
They can be identified by lack of cilia organization of nuclei and underlying nerve

Question 5

What cell type lies on the false vocal cords (vestibular folds)?

Answer 5

Respiratory epithelium. Serous glands in lamina propria.

Question 6

What cell type lies on the true vocal cords?

Answer 6

Stratified squamous epitheliums. (vocal ligament parallel elastic fibers. Vocalis muscle, skeletal, alters sounds)

Question 7

Regular rings of hyalin cartilage are found where in the respiratory tract?

Answer 7

In the trachea. There are 16-20 incomplete rings.

Question 8

Cartilage of irregular rings or plates are found where in the respiratory tract?

Answer 8

Bronchi.

Question 9

Do bronchioles contain cartilage? What is prominent in bronchioles?

Answer 9

NO. Smooth muscle is prominent in larger bronchioles, reactive, and regulatory.

Question 10

Mucosa is wavy or folded due to post-mortem contraction of smooth muscle is characteristic of what structure in the resp tract?

Answer 10

Regular bronchioles.

Question 11

Where does most regulation of ventilation occur?

Answer 11

At the level of the regular bronchioles due to the large cross sectional area, lack of cartilage, and presence of smooth muscle.

Question 12

In terminal bronchioles what are goblet cells replaced by? What are their function?

Answer 12

Clara cells. They are tall cells that share the b membrane w/ cuboidal epithelium and extend taller than the surrounding epithelium. They have dense granules in their apical cytoplasm containing protein that is secreted along with aqueous solution to moisten the epithelium.

Question 13

Outpocketings of alveoli in bronchiole walls permit gas exchange in what part of the resp tract?

Answer 13

Respiratory bronchioles

Question 14

Very thin crescent shaped nuclei are characteristic of what cell type in the alveolar septum?

Answer 14

Capillary endothelial cells.

Question 15

Alveolar macrophages are also called?

Answer 15

Dust cells.

Question 16

Compare tracheal cartilage with bronchus cartilage?

Answer 16

Tracheal cartilage rings are very uniform while bronchial cartilage is irregular.

Question 17

Compared to vessels elsewhere in the body how do vessels in the pulmonary circulation compare? (Hint: the pulmonary circulation is at a much lower pressure)

Answer 17

All blood vessels in lung sections are likely to contain red blood cells and have thinner than expected walls.

Question 18

How can bronchi be distinguished from alveoli on a glass slide?

Answer 18

The bronchi have a larger size and comparatively intense blue staining of nuclei clustered in the respiratory epithelium of their lumen.

Question 19

What are features of bronchi?

Answer 19

Irregular patches of cartilage surrounding them. Smooth muscle layer in the lamina propria is fairly prominent. There are fewer goblet cells than seen in the trachea but with very prominent ciliated pseudo stratified columnar epithelium.

Question 20

How does a bronchi differ from a bronchiole?

Answer 20

Primarily because the bronchiole has no cartilage.

Question 21

Histologically describe a Type I Pneumocyte:

Answer 21

Very flat nucleus, thin cytoplasm

Question 22

Histologically describe a Type II Pneumocyte:

Answer 22

Bulge into alveolar space, apical microvilli. Produces surfactant found at septum junctions.

Question 23

Histologically describe a endothelial cell in the alveoli

Answer 23

Lines pulmonary capillary wall. Crescent shaped nucleus visible in septum.

Question 24

Histologically describe a Vocal cord

Answer 24

Stratified squamous. No glands in mucosa. Parallel elastic vocal ligament.

Question 25

Histologically describe a vestibular fold

Answer 25

ciliated pseudo stratified columnar. Numerous serous glands in mucosa