Chapter 2 - Pulmonary Function

Question 0

Define external respiration

Answer 0

Gaseous exchange between the lungs and blood

Question 1

Define ventilation

Answer 1

Getting air in and out of the lungs

Question 2

Define internal respiration

Answer 2

Exchange of gases between blood in capillaries and body cells

Question 3

Define cellular respiration

Answer 3

Metabolic reactions and processes that take place in a cell to obtain energy from fuels such as glucose

Question 4

Mechanics of inspiration

Answer 4

Increases volume of thoracic cavity
Diaphragm contracts and flattens
External intercostals pull ribs up and out
Reduces pressure in lungs

Question 5

Mechanics of expiration

Answer 5

Decreases volume of thoracic cavity
Diaphragm and external intercostals relax
Pressure increases in lungs, forcing air out
Passive process

Question 6

Breathing during exercise

Answer 6

More muscles involved so faster breathing
Sternocleidomastoid lifts sternum, scaleless and pectorals minor which lift ribs
Internal intercostals pull ribs down and in and abs push diaphragm up

Question 7

What is the tidal volume

Answer 7

The volume of air inspired or expired per breath

Question 8

What is minute volume

Answer 8

Volume of air inspired or expired per minute

Question 9

What is equation for finding minute ventilation

Answer 9

Number of breaths (p/m) x tidal volume = minute ventilation

Question 10

How is breathing different at rest

Answer 10

Have the ability to breath in and out more air than just tidal volume
Extra inspired = Inspiratory reserve volume (IRV)
Extra expired = Expiratory reserve volume (ERV)

Question 11

What is residual volume

Answer 11

Volume of air that remains in the lungs after maximum expiration

Question 12

What is vital capacity

Answer 12

Volume of air forcibly expired after maximum inspiration in one breath

Question 13

What is total lung capacity

Answer 13

Vital capacity + residual volume

Question 14

What lung volumes increase during exercise

Answer 14

Tidal volume and minute ventilation

Question 15

What lung volumes decrease during exercise

Answer 15

IRV, ERV, Vital capacity and total lung capacity

Question 16

What lung volumes don’t change during exercise

Answer 16

Residual volume

Question 17

What is gaseous exchange at the lungs

Answer 17

External respiration is replenishment of oxygen in blood and removal of carbon dioxide

Question 18

What is partial pressure

Answer 18

Pressure exerted by individual gas within mixture

Question 19

How does oxygens partial pressure affect exchange in the lungs

Answer 19

Gases go from areas of high pressure to those of low pressure
It is important that as oxygen moves from the alveoli to the blood and then muscle, the partial pressure of oxygen of each is lower.

Question 20

What happens in gaseous exchange at the tissues (internal respiration)

Answer 20

For diffusion to occur, the partial pressure of O must be lower in the tissues than the blood
Partial pressure of CO2 is lower in blood than tissues so goes to blood to go to lungs

Question 21

What is the arterio-venous oxygen difference

Answer 21

The A-VO2 diff is the difference in the oxygen content of the arterial blood in arriving in muscles and venous blood leaving muscles

Question 22

How does the A-VO2 diff change during exercise

Answer 22

Higher difference as muscles need more O from blood
High concentration gradient for both gases so faster diffusion
Training increases diff as trained performers can extract more O from blood

Question 23

How is oxygen transported

Answer 23

3% dissolves in plasma

97% combines with haemoglobin to form oxyhemoglobin

Question 24

Where does oxygen go during exercise

Answer 24

Diffuses into capillaries to skeletal muscles

Question 25

When is haemoglobin fully saturated

Answer 25

When the partial pressure of blood is high in the alveolar capillaries of the lungs

Question 26

Where does oxygen disassociate from haemoglobin

Answer 26

At the tissues due to lower partial pressure there

Question 27

When does haemoglobin give up some of its oxygen

Answer 27

During exercise Increase in temperature of blood or muscle Decrease in partial pressure in muscles Increase in CO2 partial pressure Increase in acidity due to increase in CO2 which increases hydrogen ions which lowers pH

Question 28

What is the Bohr effect

Answer 28

Reduction of haemoglobin's affinity for oxygen due to high CO2 and decrease in pH

Question 29

What is the chain of breathing

Answer 29

``` Nose Pharynx Larynx Trachea Bronchi Bronchioles Alveoli ```

Question 30

What happens during inspiration

Answer 30

External intercostals contract so.. Lungs, ribs and sternum pushed upwards and outwards Diaphragm down, lowering pressure and increase size of thoracic cavity Pleural membrane surrounding lungs move with lungs to suck in air

Question 31

What happens during expiration

Answer 31

Intercostal muscles relax, so chest wall moves in and down Diaphragm relaxes and bulges Pressure increases and air pushed up trachea and out nose and mouth

Question 32

What is the medulla oblongata

Answer 32

It is located in the brain stem and is responsible for controlling breathing

Question 33

Quiet breathing at rest is controlled by what

Answer 33

Inspiratory control centre The medulla sends a nerve impulse down the phrenic nerve for 2 secs to external intercostals and diaphragm to contract Impulse is stopped for 3 secs where muscles relax

Question 34

Breathing during exercise is controlled by what

Answer 34

Inspiratory and Expiratory control centre

Question 35

What happens during inspiration during exercise

Answer 35

ICC sends impulse down phrenic nerve to external intercostals and diaphragm to contract harder and faster Scalene muscles, sternocleidomastoid and pectoralis minor makes inspiration deeper to deepen Tidal volume

Question 36

What happens during forced expiration during exercise

Answer 36

Impulse for ICC sent down sympathetic nervous system is cut off to the external intercostals and diaphragm ECC sends impulse to internal intercostals and abdominals to contract to reduce time taken to exhale Expiration becomes active process

Question 37

What is an active process

Answer 37

When energy is used and muscles contract

Question 38

What is a passive process

Answer 38

Energy is not used and muscles relax

Question 39

What are the baroreceptors

Answer 39

Located in blood vessels in vertebrae | Responds to blood pressure

Question 40

What are mechanoreceptors

Answer 40

Located on skin | Respond to join movement and muscle contractions

Question 41

What are thermoreceptors

Answer 41

Located on skin | Respond to heat

Question 42

What are proprioceptors

Answer 42

Located in brain | Respond to body parts position and muscle movement

Question 43

3 situations when change in oxygen in blood affects breathing rate

Answer 43

Smoking - lungs lined with tar, stops diffusion happening Asthmatic - bronchioles become inflames and mucus builds up Altitude - less oxygen in air so more breaths required