The Respiratory System II

Question 1

Whats the function of a Respiratory Membrane?

Answer 1

Exchange of O2 and CO2 between air spaces in the lungs and the blood

~0.5 m thick air-blood barrier to allow rapid diffusion of gases

Question 2

How does Voice Production occur?

Answer 2

Vocal folds are adducted (closed), air is exhaled upwards and blows apart the vocal folds setting them into a rapid vibratory pattern

Question 3

What are the four layers of Trachea?

Answer 3

Mucosa: pseudostratified ciliated columnar epithelium

Submucosa: connective tissue with seromucous glands

Hyaline cartilage: 16-20 incomplete rings (semi rigid support). Posteriorly attached to the esophagus (trachealis muscle, elastic connective).

Adventitia: outermost layer made of connective tissue that encases the C-shaped rings of hyaline cartilage

Question 4

What structures make the Respiratory zone?

Answer 4

Respiratory bronchioles, alveolar ducts, alveolar sacs (clusters of alveoli)

Question 5

What structures make the Conduction zone?

Answer 5

Lobule: arteriole, venule, lymphatic vessel, branch from a terminal bronchiole

Question 6

What are the different cells present in Alveoli?

Answer 6

Type I cells: squamous epithelial cells, continuous lining of the alveolar wall

Type II cells: scattered rounded or cuboidal cells containing microvilli, secrete alveolar fluid (surfactant)

Surfactant: mixture of phospholipids and lipoproteins (lower the tension of alveolar fluid reducing the tendency of alveolar wall to collapse)

Alveolar macrophages (dust cells): remove dust particles and

Question 7

What is the functional anatomy of the Respiratory system?

Answer 7

Conducting zone: conducts air into the lungs

Respiratory zone: site of gas exchange

Question 8

Whats Intrapulmonary pressure?

Answer 8

Pressure in the alveoli

Question 9

Whats Intrapleural pressure?

Answer 9

Pressure in the pleural cavity

Question 10

3 Physical Factors Influencing Pulmonary Ventilation?

Answer 10

Airway resistance
Alveolar surface tension
Lung compliance

Question 11

Airway Resistance?

Answer 11

During inspiration bronchioles enlarge resistance decreases

During expiration bronchioles diameter decreases resistance increases

Question 12

Alveolar Surface Tension?

Answer 12

Force exerted on the thin layer of alveolar fluid caused by the attraction of the molecules beneath

Question 13

What is Compliance?

Answer 13

Measure of lungs capacity to expand the V as a result of a change in pulmonary P

Question 14

What is Pulmonary fibrosis?

Answer 14

Reduced compliance

Question 15

What is Emphysema?

Answer 15

Increased compliance

Question 16

What is the Control of Respiration?

Answer 16

Respiratory muscles controlled by nerve impulses from respiratory center (involves neurons in the reticular formation of the medulla and pons)

Question 17

What are the affects of disease on the respiratory system?

Answer 17

Emphysema: alveolar sacs damaged and enlarged
Chronic bronchitis: respiratory passages swollen and irritated. Increase in mucous production
(Smoking)

Question 18

Oxygen transport through blood?

Answer 18

Only about 1.5% dissolved in plasma
98.5% bound to haemoglobin (Hb) in red blood cells (oxyhaemoglobin)
Heme portion of haemoglobin contains 4 iron atoms – each can bind one O2 molecule
Only dissolved portion can diffuse out of blood into cells