16 Anatomy of the respiratory tract

Question 1

Functions of the respiratory tract: (6)

Answer 1

Provides o2
Removal of CO2 
Regulates pH 
Defence against pathogens 
Produces sound
Smell

Question 2

Upper respiratory tract consists of:

Answer 2

• Nose
• Pharynx
• Larynx
• Paranasal sinuses

Question 3

What are the functions of the upper respiratory tracts?

Answer 3

• Modifies sound
• Smell
• Warms, moistens and filters air

Question 4

Functional adaptations of the nose:

Answer 4

Vibrissae 
Conchae 
Mucosa 
Rich capillary network
Olfactory muscles 
Paranasal sinuses

Question 5

What are vibrissae?

Answer 5

nose hairs - at the entrance trap dust particles

Question 6

What are conchae?

Answer 6

Shelf like projections in the lateral wall, cause turbulent (slow) airflow which allows time to moisten and warm air

Question 7

What are the functional adaptations of mucosa in the nose?

Answer 7

-pseudostratified columnar epithelium with goblet cells

Question 8

What is the purpose of the rich capillary network in the nose?

Answer 8

To warm the air

Question 9

Olfactory mucosa:

Answer 9

• located in the upper aspect of the nose

- contains receptors for smell

Question 10

What are the paranasal sinuses?

Answer 10

Air filled spaces that drain into the nasal cavity
lighten the skull and resonate sound
also lined with pseudostratified columnar epithelium with goblet cells

Question 11

What is the pharynx?

Answer 11

A communal passageway for food and air to enter the body
-Air enters the nasopharynx (posterior to the nose) and travels down the laryngopharynx (posterior to the larynx)
-Food enters the oropharynx (posterior to the mouth) and passes down into the oesophagus
N
O
L

Question 12

How many muscles do you use to swallow food?

Answer 12

28

Question 13

What is the structure of the larynx?

Answer 13

Made up of three different cartilages 
-Arytenoid
-Cricoid
-Thyroid
Lined by membranes which form the edges of vocal chords
Also includes the glottis

Question 14

How do we vary the pitch of voice?

Answer 14

By moving the arytenoid cartilage to determine how much air gets into the larynx

Question 15

What is the glottis

Answer 15

the space where air goes down. The epiglottis can close up the glottis if food passes o stop it entering

Question 16

What does the lower respiratory tract consist of?

Answer 16

Trachea
Primary bronchi
Secondary bronchi
Tertiary bronchi
Primary bronchioles
Secondary bronchioles 
Terminary bronchioles 
Respiratory bronchioles 
Alveolar ducts 
Alveolar sacs 
Alveoli

Question 17

What does the conductive portion of the resp system consist of?

Answer 17

Trachea
Primary bronchi
Secondary bronchi
Tertiary bronchi
Primary bronchioles
Secondary bronchioles 
Terminary bronchioles

Question 18

What does the respiratory portion of the resp system consist of?

Answer 18

Respiratory bronchioles
Alveolar ducts
Alveolar sacs
Alveoli

Question 19

Structure of the trachea:

Answer 19

• 4.5 cm long
• 2.5 cm diameter
• consists of C shaped rings of cartilage
• Can’t be collapsed
• Lined by pseudostratified ciliated columnar epithelium with goblet cells

Question 20

Position of the trachea

Answer 20

• anterior to oesophagus

- extends from larynx to carina

Question 21

What changes from the trachea to the bronchi?

Answer 21

• series of tubes that get smaller in diameter
• cartilage decreases
• smooth muscle increases
• epithelial cells become more cuboidal

Question 22

Structure of primary bronchi:

Answer 22

• Supply each lung
• Right is wider and more vertical than left because L is avoiding heart
• 2-3cm long
• C shaped cartilage present

Question 23

Structure of secondary bronchi:

Answer 23

• supply each lobe
• 3 on the right 2 on the left
• plates of smooth muscle with cartilage imbetween

Question 24

Structure of tertiary bronchi:

Answer 24

• supply segments of the lungs

- contain plates of cartilage

Question 25

Structure of bronchioles

Answer 25

Don’t contain cartilage

Mainly smooth muscles so can contract and dilate

Question 26

How many terminal bronchioles come from each bronchiole?

Answer 26

50-80

Question 27

Whats in the terminal bronchioles?

Answer 27

• simple columnar ciliated epithelium incase some mucus gets down there
• clara cells produce surfactant

Question 28

Whats in the respiratory bronchioles?

Answer 28

• no cilia
• clara cells
• simple cuboidal epithelia
• occasional alveoli extend from lumen so gas exchange can take place here

Question 29

What are the types of alveolar cells?

Answer 29

1 and 2
2 secretes surfactant
1 simple squamous epithelium forms wall
macrophages are present in alveoli to engulf pathogens and dust particles

Question 30

Respiratory membrane in alveoli:

Answer 30

-the basement membrane and the epithelial cells of the alveoli fuse, as do the basement membrane and endothelium of capillary making a shorter distance for diffusion

Question 31

What happens if blood pressure in the lungs gets too high?

Answer 31

If pressure in the lung capillaries gets too high fluid can be forced out into the interstitial fluid or alveoli, pushing apart the basement membranes and greatly slowing gas exchange

Question 32

What is the function of the conducting portion of the respiratory tract?

Answer 32

Warming and moistening air and conducting it to the lungs