Module D

Question 1

what is respiratory system ?

Answer 1

The respiratory system is the network of organs and tissues that help you breathe. It includes your airways, lungs, and blood vessels.

Question 2

The conducting zone

Answer 2

consists of all of the structures that provide passageways for air to travel into and out of the lungs
= Warming & humidifying process
= Removal of debris & pathogens

Question 3

the respiratory zone

Answer 3

is deep inside the lungs and is made up of the respiratory bronchioles as well as it is involves in gas exchange.

Question 4

types of pressure in and around the lungs

Answer 4

pleural pressure - pressure of fluid within the space between the lungs and chest wall. Normally negative, creating an action effect.

alveolar pressure - pressure of air inside the alveoli, negative during inspiration , positive during expiration.

Question 5

what are the mechanics of breathing

Answer 5

Inspiration - Alveolar pressure is negative resulting in pressure gradients that result in air flow into the lungs.

Expiration - Alveolar pressure rises above atmospheric pressure, becoming positive, resulting in a pressure gradient that results in airflow out of the lungs.

Question 6

lung movement occurs via:

Answer 6

• When you breathe in, or inhale, your diaphragm contracts and moves downward.
  This increases the space in your chest cavity, and your lungs expand into it.

Question 7

what is lung compliance

Answer 7

pulmonary or lung compliance, is a measure of the lung’s ability to stretch and expand.

Question 8

what are the determinants of lungs compliance

Answer 8

Two factors determine lung compliance –

1) elasticity of the lung tissue
2) surface tensions at air water interfaces.

Question 9

what is surface tension

Answer 9

Surfaces tension is the tension of the surface film of a liquid cause by the attraction of the particles in the surface layer by the bulk of the liquid, which tends to minimize surface area

Question 10

what is the 1 determinants of lungs compliance

Answer 10

Elastic forces of lung tissue - determinants d by ration of elastin and collagen fiber

Question 11

what is the 2 determinants of lung compliances

Answer 11

Surface tension of fluid lining the alveoli

• On the inside of the alveoli , surface water is attempting to contract , which collapses the alveoli
• In the alveoli, this tendency is reduced by the presence of surfactant.

Question 12

what is ventilation

Answer 12

Volume of air breathed in 1 minutes is known as the minute ventilation

VE = VT * Bf
where V T = Tidal Volume And B F = Breathing Frequency

Question 13

describe the alveolar ventilation.

Answer 13

Alveolar ventilation is the exchange of gas between the alveoli and the external environment. It is the process by which oxygen is brought into the lungs from the atmosphere

Question 14

what is dead spaces

Answer 14

Dead space is the volume of air that is inhaled and does not take part in the gas exchange because reaches alveoli that are not perfused.
V A =(VT –VD )* Bf

Question 15

Gas exchange

Answer 15

During gas exchange oxygen moves from the lungs to the bloodstream. At the same time carbon dioxide passes from the blood to the lungs

Question 16

factors influencing gas diffusion

Answer 16

1- thickness of the alveolar repertory membrane
2- membrane surface area
3- diffusion coefficient of the gas
4- partial pressure differences on either side of membrane

Question 17

Partial pressure

Answer 17

Partial pressure is the force exerted by a gas. Partial pressure is extremely important in predicting the movement of gases.

Question 18

what is the Diffusing capacity (of the respiratory membrane)

Answer 18

Volumes of a gas that will diffuse through the respiratory membrane for a particle pressure differences of 1 mmHg

Question 19

what is ventilation -perfusion ratio

Answer 19

Matching of the alveolar ventilation with the perfusion of the alveolar capillaries (with blood) expresses as VA/Q.

• For ‘optimal’ gas exchange, all alveoli would receive sufficient ventilation and alveolar blood flow.

Question 20

how is oxygen (O2) carried in the blood?

Answer 20

Hemoglobin- 4 proteins chains (2 alpha- 2 beta) each containing a a haem group and ion atom

Question 21

what is a hemoglobin

Answer 21

Hemoglobin is the iron-containing oxygen-transport metalloprotein in the red blood cells of almost all vertebrates

• Hemoglobin in blood carries oxygen from the lungs or gills to the rest of the body
• oxygen is primarily transport via hemoglobin

Question 22

transport of O2 within the circulation.

Answer 22

• Oxygen transport within the human body occurs through both convection and diffusion.
• Oxygen diffuses from both the alveoli into the
  pulmonary capillaries and the systemic capillaries into the tissues

Question 23

facts about hemoglobin

Answer 23

1- normal values are
= Males 13-18 g/dL (per 100 ml of blood)
= females 12-16 g/dL
2- 97% of O2 in blood is bound to hemoglobin
= Hb will also bind carbon monoxide and nitric oxide.
3- depending on which country you are in, you may see it spelt as hemoglobin

Question 24

Diffusion of oxygen

Answer 24

From the alveoli , the oxygen from the air you breathe enters your blood in blood vessels.

• This process is called oxygen diffusion
• Once your blood is oxygenated it carries oxygen throughout your body.

Question 25

alveoli

Answer 25

The alveoli are where the lungs and the blood exchange oxygen and carbon dioxide during the process of breathing in and breathing out.

Question 26

what are the mechanisms of transport of C02 (carbon dioxide)

Answer 26

1-Co2 in dissolves state(5-10%)
2 transported as bicarbonate ion (HCO3) ( 70%)
3- As carbaminohemoglobin (CO2 HB) (20-25%)
= in combination with hemoglobin

Question 27

3 ways of carbon dioxide is transport

Answer 27

1 - Bicarbonate
2- Carbamino haemoglobin
3- Dissolved state

Question 28

Factors that influenced O2 dissociation

Answer 28

1- Increase H+ (ions)
2- Increased CO2 (carbon dioxide)
3- Increased temperature

Question 29

Factors that influence CO2 dissociation

Answer 29

Bohr effect shows that when PCO2 (The partial pressure of carbon dioxide) is highest O2 dissociation from Hb (offloading) increases.

• The reverse is also true
• The Haldane effect states that greater binding of O2 with Hb, increases the release of CO2