Respiratory System

Question 1

What does the Conduction portion of the RS do, and where is it?

Answer 1

Brings in air. Nasal cavity, nasopharynx, oropharynx, larynx, trachea, bronchi. bronchioles and terminal bronchioles.

Question 2

What are the histological layers of the RS?

Answer 2

Mucosa, submucosa, adventitia and muscular.

Question 3

Where is Olfactory epithelium found?

Answer 3

Roof of the nasal cavity, superior part of nasal septum, and superior concha.

Question 4

What cell types is Olfactory epithelium composed of?

Answer 4

Olfactory cells, basal cells, brush cells and sustentactular (supporting) cells.

Question 5

Location and function of Brush cells.

Answer 5

Olfactory epi. Transduction of general sensation. Nerve fibers are terminal branches of CN V.

Question 6

Location and function of Olfactory cells.

Answer 6

Bipolar neurons that congregate to form CN I.

Question 7

Location and function of Basal cells.

Answer 7

Stem cells capable of becoming supporting or Olfactory cells.

Question 8

Location and function of Sustentacular/ Supporting cells.

Answer 8

Support Olfactory cells metabolically and physically.

Question 9

List functions of the Larynx.

Answer 9

Routes food and air, and contains vocal cords.

Question 10

Describe Mucosa layer of Trachea.

Answer 10

Ciliated pseudostratified epi with Goblet cells.
Brush cells have microvilli.
Endocrine cells secrete hormones and catecholamines.
Basal cells are there, they’re stem cells.
Lamina propria has collagen and elastic fibers.

Question 11

Describe Submucosa layer of Trachea.

Answer 11

Seromucous glands surrounded by collagen and elastic fibers.

Question 12

Describe Adventitia layer of Trachea.

Answer 12

C-shaped hyaline cartilage surrounded by collagen and elastic fibers.

Question 13

Describe Muscular layer of Trachea.

Answer 13

Smooth muscle that bridges the gaps between the free-ends of the C cartilage.

Question 14

Describe the Bronchi.

Answer 14

Extra-pulmonary bronchi have similar appearance to trachea, while intra-pulmonary bronchi have irregular plates of cartilage. As the branches get smaller, the bands of smooth muscle get bigger. Lamina propria has a lot of elastic fibers.

Question 15

Describe terminal bronchioles.

Answer 15

No cartilage, glands in mucosa, Goblet cells (replaced by Clara cells). Lined with simple ciliated columnar/ cuboidal epi. Laminal propria has a lot of smooth muscle and elastic fibers - important in asthma!

Question 16

Location and function of Clara cell.

Answer 16

Terminal bronchiole. Non-ciliated cells. Secrete glycosamunoglycans in response to irritation, anti-inflammatory (protein CC-16), surfactant like material and enzymes. Detoxify nitrogen dioxide. Involved in transporting water and ions like Cl.

Question 17

What does the Respiratory portion of the RS do, and where is it?

Answer 17

Blood air gas exchange. Respiratory bronchioles, alveolar ducts, alveoli.

Question 18

Describe Respiratory Bronchioles.

Answer 18

Transition between Conduction and Respiratory zones. Lining epi is simple cuboidal, non-ciliated. No Cartilage, no Goblet cells (replaced by Clara cells).

Question 19

What makes up the “Alveolar wall?”

Answer 19

Endothelial cells of blood capillaries (cont, non-fenestrated), squamous epi (Type I), secretory cells (Type II), Alveolar macrophages.

Question 20

Location and function of Alveolar secretory cells (Type II).

Answer 20

Large, round cells. Synthesize surfactant (reduces surface tension of alveoli, prevents collapse).

Question 21

What do Pores of Kohn do?

Answer 21

Allows air to pass between Alveoli.