15. Anatomy of the Respiratory Tract

Question 1

What are the structural features of the Upper respiratory tract

Answer 1

Nose and paranasal sinuses
Pharynx
Larynx

Question 2

What are the structural features of the lower respiratory tract

Answer 2

Trachea
Bronchi
Bronchioles
Alveoli

Question 3

State the function of the upper respiratory tractWarms and moistens and filters the air

Answer 3

Warms and moistens and filters the inhaled air to protect the lower respiratory tract

Olfaction (smell)

Production and resonation of sound

Question 4

State the functions of the nose

Answer 4

• Warms and moistens and filters air

- Contains receptors for smell

Question 5

What are the names of the hairs at the entrance of the nose?

What do they do?

Answer 5

Vibrissae

They trap large dust particles

Question 6

What are the concahe?

What do they do?

Answer 6

Conchae are shelf like projections that create turbulence, allows more time to warm and moisten the air.

Question 7

What are Respiratory Mucosa?

What do they do?

Answer 7

• Pseudostratified ciliated columnar epithelium with goblet cells that produce mucous to trap particles.
• Cilia waft the trapped particles to pharynx where they can be swallowed.
• Respiratory defence system

Question 8

List the 6 functional adaptations of the nose

Answer 8

• Conchae
• Vibrassae
• Mucosa
• Rich capillary network
• Olfactory mucosa
• Paranasal sinuses

Question 9

What is the role of the pharynx

Answer 9

Pharynx forms a communal passageway for respiratory and GI systems.

Question 10

State the 3 regions of the pharynx from highest to lowest.

Answer 10

Nasopharynx
Oropharynx
Laryngopharynx

Question 11

State the main functions of the larynx

Answer 11

Maintains an open airway
Prevents food and drink entering the lower respiratory tract
Sound production
Coughing and defacaetion.

Question 12

What is Olfactory mucosa?

Answer 12

Located in the upper aspect of the nose

Contains receptors for smell.

Question 13

What are Paranasal sinuses?

Answer 13

• Air filled spaces in bones around the nose (unsure still)
• Lighten the skull and resonate sound
• Secretions for the sinuses drain into nasal cavity

Question 14

What is the Glottis?

Answer 14

• The space between the vocal cords
• Usually open to allow air flow
• Closed during swallowing to prevent aspiration
• Air vibrated over the vocal cords to produce sound

Question 15

Name the 10 structures in the lower respiratory tract.

Answer 15

• Trachea
• Primary bronchi
• Secondary bronchi
• Tertiary bronchi
• Bronchioles
• Terminal bronchioles
• Respiratory bronchioles
• Alveolar ducts
• Alveolar sacs
• Alveoli

Question 16

Function of Pseudostratified Ciliated Columnar Epithelium with Goblet Cells in the Trachea.

Answer 16

• Goblet cells produce mucus = mucus layer in the lumen
• Particles inhales get trapped in the mucus layer of the nasopharynx or by secretions of the pharynx
• Cilia waft the particles back to the pharynx = swallowed + ingested

Question 17

What is the Lamina Propria?

Answer 17

• Underlying layer of areolar that supports the respiratory epithelium.
• Contains bundles of smooth muscles cells

Question 18

What happens to the series of tubes as you go further down the Bronchial Tree?

Answer 18

• Smaller in diameter
• Amount of cartilage decreases
• Amount of smooth muscle increases
• Height of epithelial cells decrease

Question 19

Name the properties of the Primary Bronchi.

Answer 19

• supply each lung
• 2-3cm long
• right is wider and more vertical than left
• C-shaped cartilages
• Pseudostratified ciliated columnar epithelium with goblet cells

Question 20

Name the properties of the Secondary Bronchi.

Answer 20

• supply lobes of the lung (3 on right, 2 on left)
• plates of cartilage
• Pseudostratified ciliated columnar epithelium with goblet cells

Question 21

Name the properties of the Tertiary Bronchi.

Answer 21

• supply segments of the lung (10 on right, 8 on left)

- plates of cartilage

Question 22

Describe the structure and properties of the Bronchioles.

Answer 22

• No cartilage
• Simple columnar epithelium with cilia
• Few goblet cells (mucus secreting)
• Smooth muscle therefore can constrict and dilate
• Each gives rise to 50-80 terminal bronchioles
• Controlled by the autonomic nervous system
• Controls airway resistance

Question 23

Describe the structure and properties of the Terminal Bronchioles.

Answer 23

• Simple columnar epithelium with cilia
• No goblet cells or mucous glands
• Clara cells – produce surfactant
• Each gives rise to 2 or more respiratory bronchioles

Question 24

Describe the structure and properties of the Respiratory Bronchioles.

Answer 24

• Simple cuboidal epithelia
• No cilia
• Clara cells – produce surfactant
• Alveoli extend from the lumen \ gas exchange occurs here

Question 25

Describe the Structure of the Alveoli.

Answer 25

• Alveolar cell layer consists mainly of simple squamous epithelium.
• Wall of alveolus is mainly formed of type I alveolar cells (pneumocytes type I).
  ○ At the sites of gas diffusion.
  ○ Unusually thin
• Large Type II alveolar cells (pneumocytes type II)
• Air crosses respiratory membrane to get into the capillary from the alveoli.

Question 26

Function of Large Type II alveolar cells (pneumocytes type II).

Answer 26

Large Type II alveolar cells (pneumocytes type II) secrete surfactant containing phospholipids and proteins, which reduces surfaces tension so alveoli can easily expand.

Question 27

Describe the structure and function of the Respiratory Membrane.

Answer 27

Made up of:

• Epithelium of Type I cell (Simple Squamous)
• Basement membrane of Type I cell
• Basement Membrane of Capillary
• Endothelium of capillary

If fluid builds up between basement membranes the it causes fluid hypertension