Respiration PHYISIOLOGY

Question 1

Functional events in respiration

Answer 1

Ventilation
Pulmonary gas exchange
Gas transport
Utilization of oxygen by cells

Question 2

What are the secondary functions of the respiratory system?

Answer 2

Regulate body pH(controlling carbon dioxide levels)
Storage(lungs have 12 percent of blood)
Defense (macrophages in alveolar cells, mucocilliary escalator trapping dust and things, and immunoglobulin/antibodies produced by lungs into bronchial mucus
Metabolic activation and inactivation of biological substances

Question 3

Which substances are inactivated by pulmonary circulation as a metabolic function of the respiratory system

Answer 3

Bradykinin, serotonin, some prostaglandins(E1, E2…), norepinephrine.
Note that only a small fraction of epinephrine is inactivated

Question 4

Which substances are not significantly affected

Answer 4

Vasopressin
Angiotensin II
Other prostaglandins A1 and A2

Question 5

Which substances are activated

Answer 5

Angiotestin Converting Enzyme

Which converts Angiotensin I to Angiotensin II. It is a powerful vasoconstrictor

Question 6

Synthesis if biological substances is a function of the respiratory system. What are examples of some of the substances synthesized

Answer 6

Phospholipid(dipalmitoyl phosphatidyl choline) component of surfactant)
Arachidonic acid metabolites(leukotrine and prostaglandins)

Question 7

Embryonic stage?

Answer 7

4-7 weeks after fertilization
Lung bud differentiation
Formation of trachea and bronchi
Pulmonary vein and artery

Question 8

Pseudoglandular stage?

Answer 8

7 to 17 weeks
Conducting airways form
Terminal bronchioles
Immature neural networks form
Pre acinar blood vessels
Lung has glandular appearance

Question 9

Canalicular

Answer 9

17 to 26
Lungs develop to respiratory bronchioles

Cartilage, muscles and blood vessels form

Question 10

Sacfular

Answer 10

27 to 36 weeks
Alveolar saccules form
Extra cellular matrix forms
Neural network formation

Question 11

Alveolar

Answer 11

36 to 2 years
Expansion of gas exchange area, nerves and capillaries.
Development of alveoli

After this, alveolar cells continue to increase in number and lung growth and expansion occur till about 18 years apparently

Question 12

Side note

Answer 12

At birth, each terminal bronchioles opens into a single alveoulus instead of a whole fully developed alveolar clustering

Question 13

Disadvantages of nasal breathing?

Answer 13

Increased resistance to air flow and more likely to be obstructed (by polyps, adenoids of congestion of the nasal mucosa)

Question 14

Mention the components of the conducting zone and the respiratory zone

Answer 14

Trachea
Bronchi
Bronchioles
Terminal bronchioles

Respiratory bronchioles
Alveolar ducts
Alveolar sacs

Question 15

Application of the composition of the walls of the airways

Answer 15

The large airways, trachea and bronchi are kept open by cartilage.
The small airways, bronchioles and alveolar ducts rely in transpulmonary pressure to keep them open
Same mechanism keeps alveolar open
Bronchilar diameter is under autonomic control

Question 16

Why is the left bronchus more obliquely slanted?

Answer 16

Because it has to extend laterally behind the arch of aorta to reach its lung hilum

Question 17

What are bronchiopulmonary segments

Answer 17

Functional unit of the respiratory system

Largest sub division of a lobe

Question 18

19 bronchiopulmonary segments. 10 on right, and 9 on left. List for right

Answer 18

Right upper lobe
Apical
Posterior
Anterior

Middle lobe
Lateral
Media

Lower lobe
Lateral basal
Medial basal
Anterior basal
Posterior basal
Apical

Question 19

List for left

Answer 19

Upper lobe
Apical
Posterior
Anterior

Middle lobe(lingula)
Superior
Inferior

Lower lobe
Lateral basal
Posterior basal
Anterior basal
Apical

Question 20

Note

Answer 20

LOOK AT SLIDE 32!

Question 21

Notes about type 1 alveolar cells(pneumocytes)

Answer 21

Thin
Simple squamous epithelial cells
Large surface area. 90 to 95 percent of alveolar surface
Cannot replicate. When undamaged, type 11 cells may proliferate and differentiate into type 1 cells
Presence of occluding junctions which prevent the leakage of tissue fluid into alveolar air space

Question 22

What are pores of Kohn

Answer 22

They are pores between alveoli which facilitate collateral ventilation in case of bronchial obstructions

Question 23

Vibrissae hairs?

Answer 23

Filter particulate matter. Found in the nose

Question 24

PH of blood?
Partial pressure of carbon dioxide
Partial pressure of oxygen

Answer 24

7.35 4o 7.45
35 - 45 mm Hg
80 - 100 mm Hg

Question 25

PH of blood?
Partial pressure of carbon dioxide
Partial pressure of oxygen

Answer 25

7.35 4o 7.45
35 - 45 mm Hg
80 - 100 mm Hg

Question 26

Function of Clara cells/club cells?

Answer 26

Secretion of surfactant

Question 27

Disadvantage of nasal breathing?

Answer 27

Increased resistance to airflow and more likely to be obstructed (by adenoids, polyps of congestion of nasal mucosa)

Question 28

Children have narrow airways up to…

Answer 28

8 years

Question 28

Children have narrow airways up to…

Answer 28

8 years

Question 29

LOOK AT SLIDE 23

Answer 29

!

Question 30

Conducting zone derive their nutrition from?

Answer 30

Bronchial circulation

Question 31

Anatomical dead space volume

Answer 31

2ml/kg

Question 32

Respiratory zone volume

Answer 32

2.5l

Question 33

The small airways are kept open by

Answer 33

Transpulmonary pressure

Question 34

Angle of deviation of left and right bronchi

Answer 34

20 to 25

40 to 45

Question 35

Slide 32

Answer 35

!!

Question 36

Components of the blood gas barrier

Answer 36

Alveolar epithelium (type 1 and 2 pneumocyted)
Alveolar basement membrane 
Interstitial space 
Capillary basement membrane
Capillary endothelium

Question 37

Total surface area of blood gas barrier in average adults and thickness

Answer 37

100 m2

0.5micrometer

Question 38

Features if bgb for gaseous exchange

Answer 38

Large surface area
Small diffusion distance
Based, 02 and co2 are lipid soluble