Respiration and Breathing 1

Question 1

What are the key events of respiration and breathing.
5 things
(Bob Eats Ten Enormous Icecreams)

Answer 1

Breathing/ ventilation (moving air in and out of lungs). Gas exchange between air in lungs and blood (external respiration: oxygen uptake and carbon dioxide removal). Gas transport around the body. Gas exchange between blood and body cells. Internal respiration (cellular metabolism: oxygen consumption and production of carbon dioxide)

Question 2

What happens in healthly lungs

Answer 2

They expand to fill the chest cavity

Question 3

What is the space between the lung and plural membrane called

Answer 3

Intraplural space

Question 4

What are the components of the upper respiratory tract

Answer 4

Nasal cavity, pharynx, larynx

Question 5

What are the components of the lower respiratory tract

Answer 5

Trachea, primary bronchus, lungs, diaphragm

Question 6

What is the purpose of the ribs

Answer 6

To protect the soft mass of the lungs

Question 7

What are alveoli

Answer 7

The mass of lungs and sight of gas exchange

Question 8

What is are the functions of the respiratory system

Answer 8

To provide a sight for gas exchange and to maintain normal levels of oxygen and carbon dioxide in systemic arterial blood

Question 9

Why does the respiratory system provide a sight for gas exchange

Answer 9

Intake of oxygen and for delivery to respiring cells and elimination of Co2 produced by respiring cells

Question 10

What is normal arterial partial pressure of oxygen

Answer 10

98mmHg/13KPa

Question 11

What is normal arterial pressure of carbon dioxide

Answer 11

40mmHg/5.3kPa

Question 12

What is respiration matched to

Answer 12

Metabolism

Question 13

What are the other functions of the respiratory system

Answer 13

Contributes to regulation of blood pH. Filters, warms and humidifies inspired air. Contains smell receptors. Produces sounds. Metabolism of biologically active chemicals

Question 14

How does the respiratory system contribute to the regulation of blood pH

Answer 14

Increased CO2 results in acidification of the body. pH must be maintained as enzymes are optimised at specific pHs

Question 15

Why does the respiratory system filter, warm and humidify air

Answer 15

Filtering air helps protect from harmful products, warming and humidifying air means diffusion takes place faster so helps oxygen uptake

Question 16

Describe the conducting zone/ dead zone

Answer 16

No gas exchange takes place. Air moves by bulk flow and is conditioned, filtered and warmed. As airways branch the space becomes narrower

Question 17

Describe the transitional and respiratory zones

Answer 17

Location of respiration, at Z17 alveoli start to appear enabling respiration to take place. Whenever alveoli occur they are encased by a capillary network which enables the delivery of oxygen to blood and removal of CO2

Question 18

When does ventilation occur

Answer 18

When active muscle force is applied to a relaxed respiratory system

Question 19

What type of process is inspiration

Answer 19

An active process and so requires ATP

Question 20

What happens during inspiration

Answer 20

The volume of the thorax is increased, as the diaphragm contracts and flatterns the external intercostal muscles contract.

Question 21

What is the most important muscle in inspiration

Answer 21

The diaphragm. If there are issues with the diaphragm assistance is needed to breathe

Question 22

What happens as the volume of the thorax increases

Answer 22

Intrapleural pressure falls. Lungs expand. Alveolar pressure is less than atmospheric pressure (pressure gradient is established). Air flows into lungs until alveolar pressure is equal to atmospheric pressure. Air moves passively due to change in volume

Question 23

What type of process is expiration

Answer 23

A passive process (so no ATP required)

Question 24

What happens during expiration

Answer 24

The diphragm and external intercostal muscles relax. The elastic recoil of the lungs and chest walls reduces the volume of the thorax (passive mechanism).

Question 25

What happens as the volume of the thorax decreases.

Answer 25

Intrapleural pressure rises. Lungs recoil. The pressure of the alveoli is greater than atmospheric pressure. Air is expelled from the lungs

Question 26

What is used to measure lung function

Answer 26

A spirometer

Question 27

What is a spirometer

Answer 27

A drum that moves to measure movement, movement data is sent to a computer

Question 28

What are spirometers useful in

Answer 28

Health diagnostics, measuring the effectiveness of treatment, monitoring disease

Question 29

What is normal tidal volume

Answer 29

1/2-1/4 of a litre

Question 30

What is maximum tidal inspiration and expiration

Answer 30

5 litres (10x bigger than normal tidal volume)

Question 31

During inspiration what resistive forces oppose airflow

Answer 31

Airway resistance. Pulmonary tissue resistance.

Inertia of air and tissues

Question 32

What is airway resistance

Answer 32

Resistance to movement of air through airways (intrinsic resistance which requires 90% of work done to overcome)

Question 33

What is pulmonary tissue resistance

Answer 33

Friction between lungs and chest wall

Question 34

What is inertia of the air and tissues

Answer 34

Coughing or sneezing results in a sudden change from static to dynamic and therefore energy is required to overcome the inertia

Question 35

During inspiration what resistive forces assist airflow

Answer 35

Elastic recoil of lungs and chest wall. Surface tension in alveoli

Question 36

What is elastic recoil of lungs and chest wall

Answer 36

The fibres are made from elastin and collagen and therefore are stretchy and recoil after expansion

Question 37

What is surface tension in the alveoli

Answer 37

The fluid lining of the alveoli dissolves oxygen from gas to aqueous, however oxygen in solution generates more surface tension due to attractive forces of the molecules in the fluid lining and the alveoli, this contributes to ejecting air