Overview of Respiratory Pathologies: Part 1

Question 1

the respiratory system

what is the respiratory system divided into structurally and functionally?

Answer 1

divided into conducting airways and respiratory airways

Question 2

the respiratory system

what 6 things do the conducting airways portion of the respiratory tract comprise?

Answer 2

• nose
• pharynx
• larynx
• trachea
• bronchi
• bronchioles (main –> Terminal)

Question 3

the respiratory system

what 4 things does the respiratory airway portion of the respiratory tract comprise of?

Answer 3

comprise of:

• respiratory bronchioles
• alveolar duct
• alveolar sacs
• alveoli

Question 4

histology of repiratory wall

what 3 things make up the respiratory epithelium in the respiratory wall from the nasopharynx to the bronchi

Answer 4

• psuedostratified columnar epithelium (in contact with basement membrane)
• Cilia
• Goblet cells

Question 5

what happens to the epithelium as the respiratory tract gets smaller, to the main bronchioles?

Answer 5

it transistions from psuedostratified columnar respiratory epithelium to JUST simple columnar epithelium

Question 6

what happens to the epithelium as the respiratory tract gets to the smaller bronchioles, terminal bronchioles, respiratory bronchioles and the alveolar ducts?

Answer 6

goes from simple columnar epithelium to simple cuboidal epithelium

Question 7

what happens to the epithelium as the respiratory tract goes from the alveolar ducts to the alveolar sacs and alveoli?

Answer 7

goes from simple cuboidal epithelium to simple squamous epithelium

Question 8

why is the simple squamous epithelium ideal in the alveoli?

Answer 8

because it enhances/facilitates gaseous exchange

Question 9

divisions of the bronchial tree

how long is the trachea in the average adult and what shape and type is its cartilage

Answer 9

• 12cm
• c shaped, hyaline cartilage

Question 10

what is a difference between the right and left bronchus in terms of size and length and what does this increase likelihood of?

Answer 10

• right bronchus is shorter and wider than left bronchus
• this means aspirated foreign materials are more likely to enter right bronchus

Question 11

what does each respiratory bronchiole branch into and what type of epithelium do they retain

Answer 11

branches into 2-11 alveolar ducts that retain cuboidal epithelium

Question 12

what are found along the walls of alveolar ducts

Answer 12

• alveolar sacs that comprise 2-4 alveoli
• single alveoli by themselves

Question 13

what is the space at the entrance from the alveolar duct to an alveolar sac referred to as?

Answer 13

the atrium

Not to be confused with atrium of the heart

Question 14

what happens to cartilage as you go down the respiratory tract, towards the respiratory bronchioles etc?

Answer 14

the cartilage disappears and is replaced by smooth muscle

Question 15

what 2 things does the absence of cartilage in the bronchioles allow for?

Answer 15

allows for:
- bronchioles to be more collapsible and responsive to changes in smooth muscle tone

• allows for fine control of airflow

Question 16

histology of alveoli

what are 2 features of type I pneumocytes, what type of epithelial cells are they in the alveoli, and what do these features allow for

Answer 16

features:
- thin
- flat

type of epithelium:
- simple squamous

these 3 features allow for rapid diffusion for gas exchange across alveolar membrane

Question 17

what type of epithelial cells are type II pneumocytes, what do they secrete and what does this prevent and how

Answer 17

• cuboidal epithelial cells
• secrete pulmonary surfactant
• prevents collapse of alveoli during exhalation by reducing surface tension of alveoli membrane

Question 18

what do alveoli macrophages do

Answer 18

• clean and sterilize alveoli spaces by engulfing and digesting inhaled microbes and pathogens

Question 19

disorders of airway and gas exchange

what 2 diseases come under COPD

Answer 19

• bronchitis
• emphysema

Question 20

define an obstructive respiratory disease

Answer 20

limitation of airflow due to obstruction of airways, causing increased airway resistance

Question 21

what are 3 ways an obstructive disease can occur and give an example of a disease with each one

Answer 21

• airway narrowing (asthma)
• loss of elasticity (emphysema)
• increased secretions (bronchitis/asthma)

Question 22

what disease encompasses both emphysema and chronic bronchitis

Answer 22

COPD

Question 23

define a restrictive respiratory disease

Answer 23

restriction of normal lung movement during respiration

Question 24

what is 1 way restrictive respiratory disease can occur and state what this means for the lung in terms of capacity

Answer 24

• reduced expansion of lung parenchyma
• this leads to decreased total lung capacity