1.2 The Respiratory System

Question 1

Define ventilation?

Answer 1

Getting air into and out of the lungs

Question 2

Define external respiration?

Answer 2

Gaseous exchange between the lungs and blood.

Question 3

Define internal respiration?

Answer 3

Exchange of gases between the blood in the capillaries and the body cells.

Question 4

Define cellular respiration?

Answer 4

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

Question 5

Describe the passage of air?

Answer 5

Air is a mixture of gases and is drawn into the body through the nose -> It passes through the pharynx and onto the larynx (voice box) -> Then down the trachea (windpipe) and into the right and left bronchus -> Air moves through each bronchus and they subdivide into secondary bronchi -> These then get progressively thinner and branch into bronchioles and then respiratory bronchioles, which lead into the alveoli.

Question 6

What’s the memory tool to remember the passage of air?

Answer 6

Nearly (Nose)
Lobbed (Larynx) 
The (Trachea)
Ball (Bronchi)
Brilliantly (Bronchioles)
Again (Alveoli)

Question 7

Define diffusion?

Answer 7

The movement of gas particles from an area of high concentration or partial pressure to an area of low concentration / partial pressure.

Question 8

Define gaseous exchange?

Answer 8

The movement of oxygen from the air into the blood, and carbon dioxide from blood into the air.

Question 9

Describe the structure of the alveoli?

Answer 9

The structure of the alveoli is designed to help gaseous exchange. Their walls are very thin (only one cell thick) which means there is a short diffusion pathway.

Question 10

What’s the function of the alveoli?

Answer 10

The alveoli are responsible for the exchange of gases between the lungs and the blood. This occurs via diffusion.

Question 11

Describe the mechanics of breathing?

Answer 11

The greater the difference in pressure, the faster air will flow. This means that in order to get air to the lungs (inspiration), the pressure needs to be lower here than in the atmosphere. To get air out (expiration), air pressure needs to be higher in the lungs than the atmosphere. Increasing the volume of the thoracic cavity (chest cavity) will reduce the pressure of air in the lungs. Decreasing the volume of the thoracic cavity will increase the pressure of air in the lungs, forcing the air out.

Question 12

During inspiration what muscles are used during breathing at rest?

Answer 12

Diaphragm

External intercostals

Question 13

During inspiration what muscles are used during exercise?

Answer 13

Diaphragm
External intercostals 
Sternocleidomastoid
Scalenes
Pectoralis minor

Question 14

During expiration what muscles are used during breathing at rest?

Answer 14

Passive: diaphragm and external intercostals just relax.

Question 15

During expiration what muscles are used during exercise?

Answer 15

Internal intercostals

Abdominals

Question 16

Define tidal volume?

Answer 16

Volume of air breathed in or out per breath.

Question 17

Define Inspiratory Reserve Volume (IRV)?

Answer 17

Volume of air that can be forcibly inspired after a normal breath.

Question 18

Define Expiratory Reserve Volume (ERV)?

Answer 18

Volume of air that can be forcibly expired after a normal breath

Question 19

Define lung volumes?

Answer 19

This is the movement of air into and out of the lungs. Taking air into the lungs is inspiration and moving air out is expiration.

Question 20

Define residual volume?

Answer 20

The amount of air that remains in the lungs after maximal expiration.

Question 21

Define minute ventilation?

Answer 21

Volume of air breathed in or out per minute.

Question 22

What is a spirometer?

Answer 22

A device that is used to measure the volume of air inspired and expired by the lungs. (The volume of air we breath in or out).

Question 23

Define partial pressure?

Answer 23

The pressure exerted by an individual gas when it exists within a mixture of gases.

Question 24

What is the function of intercostal muscles?

Answer 24

Intercostal muscles help your breath in, e.g the diaphragm flattens which allows more air to enter the lungs.

Question 25

Define the concentration/diffusion gradient?

Answer 25

Often referred to as the concentration gradient. It explains how gases flow from an area of high concentration to an area of low concentration. The steeper this gradient (difference between concentration levels at high and low area), the faster diffusion occurs.

Question 26

What’s the memory tool for Pulmonary Ventilation?

Answer 26

Pulmonary ventilation simply means breathing!

Question 27

What’s the memory tool for the order of neural/chemical control for inspiration?

Answer 27

Receptors = medulla = phrenic nerve = diaphragm and external intercostals

Question 28

What is the memory tool for the order of neural/chemical control for expiration?

Answer 28

Receptors = medulla = intercostal nerve = abdominals and internal intercostals.

Question 29

Define Celia?

Answer 29

Celia a microscopic hairlike projections that help to sweep away fluids and particles.

Question 30

Define COPD (chronic obstructive pulmonary disease)?

Answer 30

A chronic and debilitating disease and is the name for a collection of diseases such as emphysema. The main cause of emphysema is smoking. It is a long-term progressive disease of the lungs that causes shortness of breath.