A L6 (Histology)

Question 1

What forms the URT and the LRT?

Answer 1

URT
nose, pharynx and associated structures

LRT
Larynx, trachea, bronchi, lungs wand tubing within lung + alveoli

Question 2

What are the functional divisions of the resp system?

Answer 2

Conducting zone
Respiratory zone (responsible for gas exchange - alveoli)

Question 3

What are the two types of mucous membranes in the nasal cavity? where they present?

Answer 3

• Olfactory mucosa
  —-> Lines the roof of the nasal cavity (consists of olfactory receptors)
• Respiratory mucosa
  —-> lines the nasal cavity apart from the roof

Question 4

What type of cells forms the respiratory epithelium?

Answer 4

pseudostratified ciliated columnar

Question 5

What does the resp mucosa consist of?

Answer 5

• Pseudostratified ciliated columnar epithelium
• Goblet cells with epithelium
• Lamina propria (loose collagenous underlying layer)

Question 6

What is the function of cilia in the respiratory mucous?

Answer 6

They move contaminated mucous (mucociliary escalator)

Question 7

What is the function of nasal mucosa in terms of the air passing thru?

Answer 7

It warms (blood vessels), moistens and filters (through the mucous and cilia) the air

Question 8

What is the muscle that connects the ends of cartilages in the trachea?

Answer 8

Trachealis muscle

Question 9

What are the types of cells present in the respiratory epithelium (RE) in the trachea

Answer 9

• Tall pseudostratified ciliated columnar epithelium cells
• Goblet cells
• Serous cells
• Neuroendocrine cells
• Stem cells

Question 10

What are the 4 layers that form the trachea?

Answer 10

• Resp epithelium
• Lamina Propria (loose, highly vascular supporting tissue)
• Submucosa (mixed seromucinous glands)
• Fibroelastic tissue between cartilage rings

Question 11

Where is smooth muscle present in the trachea?

Answer 11

Its present in small bundles mainly in the fibroelastic tissue which is located between the cartilage rings (behind the trachealis muscle)

Question 12

What is lamina propria?

Answer 12

It is loose, highly vascular supporting tissue

Question 13

Where are mixed seromucinous glands present in the trachea?

Answer 13

IN THE SUBMUCOSA

Question 14

Where is the fibroelastic tissue present in the trachea?

Answer 14

Between the C-shaped cartilage rings

Question 15

What are the changes in tissue composition as you move down the resp tract?

Answer 15

• The supporting connective tissue (cartilage) changes ::: The c-shaped cartilage rings are replaced by cartilage plates
• The type of epithelium lining the trachea changes (it decreases in height):
  —-> Goes from pseudostratified columnar epithelium —> Simple columnar —-> Simple cuboidal
• There’s and increase in the amount of smooth muscle present

Question 16

List the divisions of the resp tract as you move down it. And state which ones are conducting vs respiratory zone

Answer 16

CONDUCTING ZONE:
Trachea –> Main/primary bronchus –> Lobar/secondary bronchus –> Segmental/tertiary bronchus –> Bronchioles –> Terminal bronchiole

RESPIRATORY ZONE:
Respiratory bronchiole –> Alveolar duct –> Alveolar sac

Question 17

What is the last division of the conducting zone

Answer 17

Terminal bronchiole

Question 18

What is the first division of the respiratory zone?

Answer 18

Respiratory bronchioles

Question 19

What is the role of clara cells? Where are they found

Answer 19

Found in the respiratory bronchioles
- Secrete surfactant
- Act as stem cells
- Contain enzymes that detoxify substances

Question 20

Answer 20

Pseudostratified ciliated columnar epithelium

Question 21

Answer 21

Nasal mucosa
– RE - epithelium
V - BVs
S - serous glands
M - mucous glands

Question 22

Answer 22

Resp. epithelium (pseudostratified ciliated columnar with goblet cells)
w/ layer of lymphoid tissue below (nasopharyngeal tonsils/adenoids)

Question 23

What structure? Name the 4 layers

Answer 23

Trachea
- Resp epithelium (pseudostratified ciliated columnar with goblet cells, serous cells, neuroendocrine cells and stem cells )
- Lamina propria ( loose, highly vascular supporting tissue)
- submucosa (seromucinous glands)
- Fibroelastic tissue (btwn cartilage)

Question 24

Which layer would a majority of the vasculature be located in the trachea

Answer 24

in the lamina propria

Question 25

What is the function of neuroendocrine cells?

Answer 25

They secrete hormones that regulate muscle tone
(present in trachea and bronchioles)

Question 26

Differentiate between how the structure of the airway changes as you move further down in terms of epithelium, the layers of tissue, cartilage, supporting tissue present (lamina propria), smooth muscle, glands

Answer 26

Look at google doc