Histology

Question 1

Functions of respiratory system?

Answer 1

Supplies Oxygen to the blood for transport around the body
Removes CO2 that has accumulated in the blood from tissues in the body
Phonation
Olfaction
Lungs function in BP control via renin-angiotensin system

Question 2

Phonation?

Answer 2

Vocalization

Question 3

Olfaction?

Answer 3

Smelling

Question 4

Passage of air?

Answer 4

• Enters through the mouth and nose
• Travels via pharynx and larynx into trachea
• Trachea branches into bronchi which convey air to lungs
• Each bronchus divides into smaller bronchi then bronchioles
• Bronchioles terminate into alveolar sacs

Question 5

What does the nasal cavity provide an area for?

Answer 5

Warming,
Moistening & The air
Filtering

Question 6

Structure of nasal cavity?

Answer 6

• Initial part (Vestibule) is lined by keratinised, stratified squamous epithelium cells
• Deeper into epithelium keratin is lost
• Further in the epithelium changes to epithelium that lines nearly all of the rest of the conducting part of the respiratory system

Question 7

What type of epithelium lines the conducting part of respiratory system?

Answer 7

Pseudostratified cliliated columnar epithelium with goblet cells

Question 8

What is underneath the Respiratory Epithelium?

Answer 8

Lamina propria

Question 9

Lamina propria?

Answer 9

Band of loose cocnnective tissues containing seromucous glands and thin walled venous sinuses.

Question 10

What does the oropharynx do?

Answer 10

Transmits both air and swallowed food

Question 11

Adaptions of oropharynx to transmit air and food?

Answer 11

Must resist abrasion
Lined by non keratinized, stratified, squamous epithelium cells
(as is the anterior surface and upper part of posterior surface of epiglottis)

Question 12

Structure of larynx?

Answer 12

• Walls are made up of cartilage and epithelium
• Surfaces lined with respiratory epithelium
• Excluding vocal folds and adjacent structures which are covered in stratified squamous epithelium

Question 13

Placing of trachea?

Answer 13

Continuous with larynx and terminates by dividing into main bronchi

Question 14

Structure of trachea?

Answer 14

• 15-20 C shaped cartilage rings
• Open side of C is spanned by fibroelastic tissue and smooth muscle
• Wall of trachea covered with respiratory epithelium,backed by basal lamina and lamina propria then submucosa

Question 15

Walls of bronchus are made up of?

Answer 15

Respiratory epithelium
Lamina propria
Muscularis (Ring of smooth muscle & submucosa)

Question 16

Bronchioles?

Answer 16

Smaller airways lacking cartilage and glands that are 1mm in diameter

Question 17

Epithelium as you travel further down bronchioles?

Answer 17

Cuboidal instead of columnar

Question 18

Smooth muscle of the bronchioles?

Answer 18

Respond to parasympathetic innervation and histamine and other factors by constricting and contracting the diameter of bronchiole.
Plays a significant role in asthma attacks and allergic reactions

Question 19

Terminal bronchioles structure?

Answer 19

Lined with cuboidal, ciliated epithelium

Contain non ciliated club cells (Clara cells) that project above level of adjacent ciliated cells

Question 20

Roles of Clara/Club cells?

Answer 20

Stem cells
Detoxification
Immune modulation
Surfactant production

Question 21

What are terminal bronchioles?

Answer 21

Smallest bronchioles that lack respiratory function (gas exchange)
These branch to give rise to give the first part of respiratory tree that has respiratory function- respiratory bronchioles

Question 22

What interrupts continuity of respiratory bronchioles?

Answer 22

Alveoli

Question 23

Cells of alveoli?

Answer 23

Discontinuous Squamous type 1 alveolar cells