Respiratory 1

Question 1

What is the breathing ?

Answer 1

Breathing is the process of oxygen and car-oxygen exchange between the atmosphere and body tissue

Question 2

What are the steps of breathing

Answer 2

1-external breathing (exchange of gases between the atmosphere and lungs )
2-gases diffusion throughout aerohematic barrier
(Between alveoli and blood )
3-transport of gases
4-diffusion of gases through the capillaries walls
(Between blood and tissue)
5 - internal breathing , oxidative reaction in the cell ( mitochondria)

Question 3

The first step of breathing done by ?

Answer 3

Lungs

Question 4

Lung contents ?

Answer 4

-Alveoli
- airways ( bronchial tree ) includes
Tracheas
Bronchi
Bronchioles

Question 5

Explain the Airways

Answer 5

airways ( bronchial tree ) includes
Tracheas
Bronchi
Bronchioles
- there is 22 binary fission generation of airways
-1- the first one is trachea division into two main bronchi
-2- the 16 generation is bronchi transferring to terminal bronchioles ( which don’t take a part in gas exchange)
-3- from the 17th binary fission generation respiration bronchi begin ,
up to the 19th generation there Are single alveoli
-4- the amount of alveoli increasing by each bronchioles division

Question 6

When the amount of alveoli is increasing

Answer 6

Its increasing by each bronchioles division

Question 7

What is the alveolar duct

Answer 7

Its the alveolar sacs that fully covering the 20-22 respiratory bronchioles divisions

Question 8

What is the dead space ?

Answer 8

Dead space its space which there is no gas exchange reaction in the airway
Until the level of terminal bronchioles where its the dead space end and the gas exchange begin

Question 9

What is the volume of the dead space?

Answer 9

150 ml

Question 10

Why respiratory dead space was used to be called ” harmful “

Answer 10

Bcs it decreases the volume if the air involved in the gas exchange

Question 11

What the significance importance of the respiratory dead space ?

Answer 11

Higher value in clinical situation for diagnostic and prognostic and therapeutic, through it we can messur the expired Co2

Question 12

In normal condition what is active and what is passive ?

Inhalation , exhalation

Answer 12

Inhalation is active

Exhalation is passive

Question 13

Explain the exhalation effector

Answer 13

Is implemented by graviton and elastic qualities of pulmonary parenchyma , that of airways and thorax

Question 14

Forced inspiration and expiration are always active ? ( yes or no )

Answer 14

Yes

Question 15

What is the pleural sac function

Answer 15

Its fundamental importance in implementation of inspiration and expiration mechanism

Question 16

Explain the pleural sac ( pleural cavity ) pressure

Answer 16

In the pleural sac the pressure is always negative which is -4 mm hg

In other way 
Lung pressure ( inter pulmonary pressure) is equal the atmospheric pressure which is 760 mm hg 

So while the lung trying to expands the atmospheric pressure is pushing and the pleural cavity in between them

Question 17

What is the transpulmonary pressure

Answer 17

Its gradient of pressure between the pleural cavity and alveolar ( interpulmonary )

Question 18

What is the thoracic pressure?

Answer 18

Its pressure between pleural cavity and atmospheric

Question 19

What is the respiratory pressure ?

Answer 19

Its pressure between alveolar and atmospheric

Question 20

What is the forces that control the movements or the pressure of the lungs ?

Answer 20

1 - the transpolmonary pressure which is always directed from alveoli to the pleural cavity from inside to out side and aims to expand the lungs

2 - the elastic recoil of the lungs
Which aims to compress the lungs

If these 2 forces are equal thats mean the lung doesn’t move

Question 21

Explain the mechanism of inhalation

Answer 21

Start with reducing inspiratory mc , the pleural cavity expands and the it pressure get even more negative , transpolmonary pressure increases and elastic recoil of the lungs becomes greater , the lungs expands , air enters inhalation takes place

Question 22

Explain the exhalation mechanism?

Answer 22

Its begins with relaxation of the inspiratory mc , in this case , due to gravity the thorax is lowered, pleural cavity decreases , and it pressure get even less negative , the transpolmonary pressure decreases and becomes less then the elastic recoil
And because id the action if the lungs parenchyma subside and exhalation takes place

Question 23

How is elastic recoil created ?

Answer 23

• 1- first by the elastin of alveoli and bronchial tree
• 2- by cartilage tissue of the bronchi
• 3- and 2/3 of this force is created by a surfactant

Question 24

What is the surfactant ?

Answer 24

Its a think layer of liquid , which the alveoli are covered from the inside
And bcs its liquid, it has the force of surface tension
And this force its the main component of the elastic recoil of the lungs
And the function of it to squeeze the lung on the other side it has low density and accordingly has low surface tension

Question 25

If the surfactant had a water density , this would lead to a sharp increase in elastic properties and the lung would completely shrink ?

Answer 25

No , bcs the surfactant is liquid and its incompressible , this prevent the collapse of the alveoli at the most for ed expiration and adhesion of their walls

Question 26

How o2 and co2 transported ?

Answer 26

By two ways

1-Free stats
2-connected states

Question 27

What is the free states mean ?

Answer 27

Free states are physically dissolved species

Question 28

Any gas can dissolved in the liquid ?

Answer 28

Yes

Question 29

Explain the ways of transporting of o2

Answer 29

1- in dissolved form
2- in connection with Hb which named
Oxyhemoglobin

Question 30

Explain the ways transporting of Co2

Answer 30

1- in dissolved form
2- in connection with Hb which named
Carbhemaglobin
3- in form fo acidic salts of carbonic acid
Ex: hydrocarbons and potassium and sodium

Question 31

Why do we need free forms of gas transportation?

Answer 31

Bcs its necessary for gas exchange during the breathing duo the 2 and 4 stages of breathing are carried out

The bound forms can’t diffuse so they can’t participate in gas exchange

Also bcs the pressure
The free form when it’s dissolve its make partial pressure
And gases moves always from higher to lower partial pressure

Question 32

Partial pressure how its created ?

Answer 32

Its created only by dissolving the gas in the liquid

Question 33

If there is no dissolved gas there is liquid?

Answer 33

No

Question 34

How gases moves betwen the pressure

Answer 34

They move from one medium to another but should be there is different in the medium
By simple way from higher pressure to lower partial pressure

Question 35

When o2 dissolved in the liquid how much pressure created ?

Answer 35

O2- Arterial 100 mm hg

Venous -40 mm hg

Question 36

Explain the gases moving

Answer 36

The difference in partial pressure of o2 between the alveoli and venous blood , as well as between arterial blood and tissue

Cussed the diffusion of the gas from the alveoli into the blood and from the blood into the tissue

Question 37

What is the important component in the lung volume list much of practical significance

Answer 37

Vital capacity
Functional residual capacity
And its depends on the number of parameters

Question 38

What can effect the VC and functional resdual

Answer 38

• Age ,especially after 40 years old owning to loss of the lung elasticity and increasing restriction of thoracic mobility
• sex : the average vc of women is smaller about 25% then the men
• size
• position of the body
• trained people

Question 39

what is the main component of elastic recoil of the lungs

and what is function ?

Answer 39

the surface tension

its function to squeeze the lung