Respiratory: - Lecture 3. Respiratory System Histology.

Question 1

What are the functions of the respiratory system?

Answer 1

Supplies oxygen to the blood for delivery to cells throughout the body. Removes carbon dioxide that has been accumulated in the blood from the tissues of the body.

Question 2

What are the componetns of the respiratory system?

Answer 2

Nasal Cavity Nasopharynx Oropharynx Laryngealpharynx Larynx Trachea Carina Bronchi Lungs

Question 3

What is the function of the nasal cavity?

Answer 3

1. Warming inspired air. 2. Moistening inspired air. 3. Filtering inspired air.

Question 4

What epithelium is present on the nasal cavity?

Answer 4

Olfactory epithelium

Question 5

What is the initial part of the nasal cavity called?

Answer 5

The Vestibule

Question 6

What is the Vestibule of the nasal cavity lined with?

Answer 6

Keratinised stratified squamous epithelium

Question 7

How does the epithelium change as you move deeper into the nasal cavity?

Answer 7

Keratin is lost Changes to Respiratory Epithelium (pseudostratified ciliated columnar epithelium with goblet cells)

Question 8

What is Respiratory epithelium?

Answer 8

pseudostratified ciliated columnar epithelium with goblet cells

Question 9

What is depicted in this picture and what are the corresponding parts?

Answer 9

Superior to Inferior

• Respiratory Epithelium
• Basal Bodies
• Cilia

1. Pseudostratified ciliated columnar epithelium
2. Goblet Cell
3. Basal cell (stem cell)

Question 10

What are the layers of tissue present in respiratory epithelium?

Answer 10

Epithelium

Basal Lamina

Lamina Propria

Question 11

What are the parts of the Nasal Cavity present here?

Answer 11

• Frontal Sinus
• Superior Concha
• Middle Concha
• Inferior Concha
• Nasal Cartilage
• Nostril
• Upper lip
• Opening of Maxillary sinus
• Tongue
• Soft Palate
• Adenoids
• Spehnoids sinus
• Cribiform plate
• Olfactory bulb

Question 12

What is under the respiratory epithelium?

Answer 12

The Lamina Propria

Question 13

What does the lamina propria consist of?

Answer 13

A band of connective tissue containing seromucous glands (M and S) and a rich venous plexus (V) which can quickly engorge with blood and ‘block’ the nose.

Question 14

What type of lining is on the Oropharynx?

Answer 14

non-keratinized stratified squamous epithelium

Question 15

What type of lining is on the lingual surface and upper surface of the epiglottis?

Answer 15

non-keratinized stratified squamous epithelium

Question 16

What type of lining does the Larynx have?

Answer 16

• Larynx has a respiratory epithelium lining
• Vocal folds have a stratified squamous epithelium.

Question 17

What type of epithelium does the Vocal folds have?

Answer 17

Stratified squamous epithelium.

Question 18

How many pieces of cartilage does the trachea contain?

Answer 18

15-20 C shaped pieces of cartilage.

Question 19

What is the open sides of the C cartilaghe spanned by?

Answer 19

Fibroelastic Tissue and smooth muscle (Trachealis muscle)

Question 20

What is the anatomy of the trachea?

Answer 20

• C shaped Cartilage - ends points into the oesphagus
• Adventita (adipose tissue)
• Trachealis muscle
• Submucosal glands
• Vagus nerve
• Lamina Propria
• Submucosa with a seromucous gland

Question 21

What type of lining does the trachea have?

Answer 21

Respiratory Epithelium

Question 22

What anatomy is present in the trachea?

Answer 22

• Epithelium
• Basal Lamina
• Lamina Propria
• Submucosa
• Seromucous glands

Question 23

Describe the histolgy of the bronchi

Answer 23

The trachea divides into 2 main (primary) bronchi (singular, ‘bronchus’) which divide further within the lung. The ‘rings’ of hyaline cartilage are replaced by irregularly shaped cartilage plates. The epithelium is respiratory in type, with the lamina propria containing a discontinuous layer of smooth muscle and seromucous glands.

Question 24

How does the Bronchial tree vary as you move along it?

Answer 24

• Bronchi
• Segmental Bronchus
• Large subsegmental Broncni
• Small subsegmental bronchi
• Bronchioles
• Terminal Bronchiole
• Lobule
• Alveolus

Question 25

What is the structure of broncholes?

Answer 25

• Less that 1 mm
• Lack Cartilage
• Contain a few goblet cells
• Epithelium height decreases from columnar to coidal as you move down
• Lamina propria is composed of smooth muscle, elastic and collagenous fibres

Question 26

Describe how a bronchiole smooth muscle will look if affected by an allergic reaction or asthma attack?

Answer 26

• Constriction of the diameter
• Contraction
• Looks crinkled

Question 27

What are the terminal bronchioles lined by?

Answer 27

• cuboidal ciliated epithelium

Question 28

What are the roles of clara cells?

Answer 28

• Stem cells
• Detoxification
• Immune Modulation
• Surfactant production

Question 29

How can the respiratory system be divided into two parts?

Answer 29

1. The Conducting Portion - Trachea to Terminal Bronchiole
2. The Respiratory Portion - Respiratory Bronchiole to Alveolar sac

Question 31

What epithelium lines the alveoli?

Answer 31

• Type 1 alveolar cells - simple squamous epithelium cells
• Type 2 alveolar cells -

Question 32

What is the name given to alveolar cells?

Answer 32

Pneumocytes

Question 33

How do Alveoli protect themselves?

Answer 33

• Alveolar Macrophages (dust cells)
• Located either in the septa or migrating over the luminal surfaces of the alveoli, phagocytosing inhaled particles
• They typically will migrate up the bronchial tree, transported by ciliary action, to the pharynx where they are swallowed

Question 34

What does the alveolar wall act as?

Answer 34

The air-blood barrier