Histology of the respiratory system

Question 1

What are the parts of the respiratory tract?

Answer 1

Conducting part

Respiratory part

Question 2

What is meant by the conducting part of the respiratory tract?

Answer 2

Air passes through here

but no gas exchange occurs

Question 3

What are the actual conducting parts of the respiratory tract?

Answer 3

Nasal cavity

Pharynx

Larynx

Trachea

Bronchi

Terminal bronchioles

Question 4

What is meant by the respiratory part of the respiratory tract?

Answer 4

Where gas exchange takes place

Question 5

What are the actual respiratory parts of the respiratory tract?

Answer 5

Respiratory bronchioles

Alveolar ducts

Alveolar sacs

Alveoli

Question 6

What covers the surface of the nasal cavity?

Answer 6

Mucosa

Question 7

What are the different types of mucosa in the nasal cavity?

Answer 7

Nasal mucosa

Olfactory mucosa

Question 8

Where are the nasal and olfactory mucosa located in the nasal cavity?

Answer 8

Olfactory mucosa is located in the superior posterior region of the nasal cavity

Nasal mucosa is located everywhere else

Question 9

What type of epithelium lines the nasal mucosa?

Answer 9

Pseudostratified ciliated epithelium

Goblet cells

Question 10

What is the function of goblet cells in the nasal mucosa?

Answer 10

Produce mucus

Question 11

What is the function of mucus in the nasal cavity?

Answer 11

Trap particles, bacteria etc.

Question 12

What is the function of the cilia in the nasal mucosa?

Answer 12

Beat

waft mucus containing particles, bacteria etc. down to oropharynx to be swallowed

Question 13

What does the lamina propria of the nasal mucosa contain?

Answer 13

Serous glands, mucous glands

Lots of blood vessels

Question 14

What is the function of the mucous glands in the nasal mucosa?

Answer 14

Secrete mucus

Question 15

What is the function of the serous glands in the nasal mucosa?

Answer 15

Secrete watery substance

Question 16

What is the function of the watery substance secreted by the serous glands in the nasal mucosa?

Answer 16

Humidify the inspired air

Question 17

What is the function of the rich blood supply of the nasal mucosa?

Answer 17

Warms the inspired air

Question 18

How does the olfactory mucosa compare to the nasal mucosa?

Answer 18

Contains olfactory neurons

Question 19

What is the function of the olfactory neurons?

Answer 19

Special sensory - smell

Question 20

What is the wall of the trachea made up of?

Answer 20

Mucosa

Submucosa

Hyaline cartilage

Adventitia

Question 21

What type of epithelium lines the mucosa of the trachea?

Answer 21

Pseudostratified ciliated epithelium

Goblet cells in between

Question 22

What is significant about the basement membrane of the epithelium of the trachea?

Answer 22

Thick

Question 23

What does the submucosa of the trachea contain?

Answer 23

Seromucous glands

Trachealis muscle

Question 24

What is the function of the seromucous glands in the submucosa of the trachea?

Answer 24

Secrete watery-mucus substance

Question 25

What is the function of the hyaline cartilage in the trachea?

Answer 25

Prevent collapse of the trachea during inspiration

Question 26

What shape is the hyaline cartilage of the trachea?

Answer 26

C shaped rings

Question 27

How does the trachealis muscle relate the C-shaped rings of hyaline cartilage?

Answer 27

Trachealis muscle joins the free ends of the C-shaped rings

Question 28

What is the function of the smooth muscle outside of the lamina propria in the primary bronchi?

Answer 28

Contracts to give bronchoconstriction Relaxes to give bronchodilation

Question 29

How do the walls of the primary bronchi compare to the wall of the trachea?

Answer 29

Primary bronchi have layer of smooth muscle outside of lamina propria In primary bronchi, the hyaline cartilage forms a complete circle, not C-shaped

Question 30

How do the walls of the secondary and tertiary bronchi compare to the walls of the primary bronchi?

Answer 30

In secondary and tertiary bronchi, the hyaline cartilage forms a crescent shape, not a complete circle

Question 31

How do the walls of terminal bronchioles compare to the walls of secondary and tertiary bronchi?

Answer 31

Terminal bronchiole has simple ciliated columnar epithelium, Clare cells, no goblet cells Terminal bronchiole has no seromucous glands in its submucosa Terminal bronchiole has no cartilage

Question 32

How do the walls of respiratory bronchioles compare to the walls of terminal bronchioles?

Answer 32

Respiratory bronchioles have simple cuboidal epithelium

Question 33

What is the function of Clara cells?

Answer 33

Produce surfactant

Question 34

Why are there no seromucous glands and goblet cells in the terminal bronchioles?

Answer 34

Bronchioles have narrow lumen | mucus would narrow the lumen, close the lumen

Question 35

If the walls of terminal bronchioles have no cartilage, how are they held open during inspiration?

Answer 35

By the pull of the surrounding alveoli

Question 36

What is an alveolar sac?

Answer 36

Air space which many alveoli open into

Question 37

What is an alveolar duct?

Answer 37

Airway which many alveoli open into

Question 38

What are the walls of alveoli made up of?

Answer 38

Simple squamous epithelial cells Macrophages Pulmonary capillaries Elastic and reticular fibres

Question 39

What are the types of simple squamous epithelial cells lining alveoli? Which is more common?

Answer 39

Type 1 pneumocytes - more common Type 2 pneumocytes

Question 40

What is the function of type 1 pneumocytes in the alveoli?

Answer 40

Gas exchange

Question 41

What is the function of type 2 pneumocytes in the alveoli?

Answer 41

Produce and secrete surfactant

Question 42

What lies between the pneumocytes and the pulmonary capillaries?

Answer 42

Basement membrane of both the endothelium of the pulmonary capillaries and of the pneumocytes fused together as one

Question 43

How are the type 2 pneumocytes differentiated from the type 1 pneumocytes?

Answer 43

Type 2 pneumocytes contain lamellar bodies

Question 44

What are lamellar bodies of type 2 pneumocytes?

Answer 44

Vesicles containing surfactant

Question 45

What happens to the lamellar bodies of type 2 pneumocytes?

Answer 45

Exocytosed

Question 46

What is the function of the macrophages of the alveoli?

Answer 46

To phagocyose particles or bacteria in the alveoli

Question 47

How does the lumen of the respiratory tract change as you go down the tract?

Answer 47

Decreases in diameter

Question 48

How does the thickness of the walls of the respiratory tract change as you go down the tract?

Answer 48

Decrease in thickness