Lecture 15

Question 1

What are the components of the lower respiratory tract?

Answer 1

Larynx
Trachea
Bronchi
Bronchioles
Alveoli

Question 2

What are the functions of the LRT?

Answer 2

Conduct air to and from gas exchange
Complete cleaning, warming and humidifying
Provide a barrier between the air and blood and a large surface area for gas exchange

Question 3

Location and structure of the Larynx?

Answer 3

Anterior to the esophagus, from hyoid bone to trachea

Thyroid cartilage gives structure.

Question 4

Functions of the Larynx?

Answer 4

Passage for air only
Respiratory cleaning, warming etc
- Cartilages protect and maintain. open airway
- Epiglottis closes over airway when swallowing

Question 5

What is the glottis?

Answer 5

voicebox
The membranes that vibrate as air passes over.
Location of vocal cords

Question 6

Features of vocal folds?

Answer 6

• “true” Vocal cords
• passing air causes vibrations = sound waves
• Normal phonation
• Testosterone affects cartilage and muscle, resulting in longer thicker folds = deeper voice

Question 7

Features of vestibular folds?

Answer 7

• “false” vocal cords
• Superior to folds
  prevent foreign object entry to glottis
• can produce very deep sounds

Question 8

Location of the trachea?

Answer 8

Anterior to the esophagus, between larynx and primary bronchi

Question 9

Function of trachea?

Answer 9

Maintain patent airway.
Trachealis contracts for coughing.
Clean, warm, humidify air

Question 10

Structure of the trachea?

Answer 10

C-shaped cartilage rings.
Ends connected by band of smooth muscle: trachealis.
Many elastin fibres in lamina propria/submucosa layers

Question 11

Role of the Mucociliary escalator?

Answer 11

Removes debris to the pharynx, to be swallowed and digested.

• Mucus from goblet cells and mucous gland coat surface of epithelium.
• Debris becomes trapped.
• Cilia moves mucus to pharynx

Question 12

How many lobes do the lungs have?

Answer 12

lobes on the right and 2 lobes on the left

Question 13

What is a Hilum?

Answer 13

connects lungs to their supporting structures and where pulmonary vessels enter and exit .

Question 14

Where is the apex located

Answer 14

superior region of the lung

Question 15

What is the costal surface?

Answer 15

Outer surface against ribs

Question 16

Where is the base located

Answer 16

Inferior, sits on diaphragm

Question 17

Structure of the Bronchial tree?

Answer 17

Trachea branch into primary bronchi, branch into secondary (lobar) bronchi, branch into tertiary (segmental) bronchi, then into bronchioles, keeps branching getting deeper into lungs until reaches terminal bronchioles.

Question 18

What type of epithelium is found in the trachea, and bronchi?

Answer 18

Respiratory

Question 19

What type of epithelium is found in the bronchioles?

Answer 19

Cuboidal

Question 20

Structure of the Respiratory Zone?

Answer 20

respiratory zone is found deep inside the lungs and is made up of the respiratory bronchioles, alveolar ducts, and alveoli. These thin-walled structures allow inhaled oxygen (O2) to diffuse into the lung capillaries in exchange for carbon dioxide (CO2).

Question 21

Features of Alveoli>

Answer 21

Alveolar walls are very thing: simple squamous epithelium on a thin basement membrane.
Large surface area.
External surface of alveoli covered in fine network of pulmonary capillaries.

Question 22

Structure of Alveolus?

Answer 22

Each alveolus is cup-shaped with very thin walls. It’s surrounded by networks of blood vessels called capillaries that also have thin walls. The oxygen you breathe in diffuses through the alveoli and the capillaries into the blood.

Question 23

What is the role of type 1 pneumocytes?

Answer 23

SQUAMOUS
gas exchange.
forms the wall of alveoli

Question 24

What is the role of type 2 pneumocytes?

Answer 24

CUBOIDAL
Scattered amongst type 1.
Secrete surfactant, a complex lipoprotein that reduces the surface tension of alveolar fluid.

Question 25

Role of roaming macrophage?

Answer 25

Remove debris that makes it to alveoli

Question 26

Role of respiratory membrane?

Answer 26

Capillary

Connection to neighbouring alveoli

Question 27

Why are alveoli connected?

Answer 27

So gas can flow through

Question 28

Structure of the Respiratory Membrane?

Answer 28

(Blood air barrier)

• Alveolar cell layer
• fused basement membrane of alveolar, epithelium and capillary endothelium.

Question 29

What causes the larynx to become narrower?>

Answer 29

Less cartilage support, more smooth muscle and flattening of epithelia