Anatomy of the respiratory system

Question 1

What does the respiratory system do?

Answer 1

Provides oxygen to all living tissue in your body, and removes waste products such as carbon dioxide, heat and water vapour.

Question 2

What does the upper respiratory tract include?

Answer 2

The nose, nasal cavity, mouth, pharynx and larynx.

Question 3

What does the lower respiratory tract include?

Answer 3

The trachea, bronchi and lungs.

Question 4

What are the 2 phases of breathing/pulmonary ventilation?

Answer 4

1) Inspiration (breathing in)
2)Expiration(breathing out)

Question 5

What happens during inspiration?

Answer 5

-Intercostal muscles contract to lift ribs upwards and outwards
-Diaphragm moves downwards
-Expansion of the thorax in all directions causes pressure in the lungs to drop below atmospheric pressure so air is drawn into the lungs

Question 6

What happens during expiration?

Answer 6

-Intercostal muscles relax
-Diaphragm relaxes and moves upwards
-Ribs retract downwards and inwards
-Pressure in the lungs increases so air is pushed out of the body

Question 7

What is gaseous exchange?

Answer 7

The process in which one type of gas is exchanges for another

Question 8

How does gaseous exchange occur in the lungs?

Answer 8

It occurs by diffusion between air in the alveoli and blood in the capillaries surrounding their walls. It delivers oxygen from the lungs to the bloodstream while removing carbon dioxide.

Question 9

What is diffusion?

Answer 9

The process by which a substance such as oxygen passes through a cell membrane either to get into the cell or to get out of the cell. Substances move by diffusion from an area where they are MORE concentrated to an area where they are LESS concentrated.

Question 10

What is your respiratory rate?

Answer 10

The amount of air you breathe in 1 minute.
For a typical 18 year old this is 12 breaths per minute at rest but it can increase by as much as 30-40 breaths per minute during exercise.

Question 11

What is tidal volume?

Answer 11

The volume of air breathed in and out with each breath.
Normally this represents 500ml of air breathed, both inhaled and exhaled.
During exercise it increases

Question 12

How is tidal volume used?

Answer 12

Approximately two thirds (350ml) reaches the alveoli where gaseous exchange occurs.
The remaining 150ml fills the pharynx, larynx, trachea, bronchi and bronchioles and is known as dead or stationary air.

Question 13

What is minute volume?

Answer 13

The volume of air passing through the lungs each minute, determined by the breathing rate and the amount of air taken in with each breath.

Question 14

How much air do the lungs usually contain?

Answer 14

They usually contain 350ml of fresh air, 150ml of dead air and 2500ml of air that has already undergone gaseous exchange with the blood.

Question 15

What is residual air and what is its purpose?

Answer 15

Its the air remaining in the lungs after maximal expiration. The lungs are never fully emptied of air otherwise they would collapse.
This volume is around 1200ml for an average male.

Question 16

What is vital capacity?

Answer 16

The amount of air that can be forced out of the lungs after maximal inspiration.
This volume is around 4800ml.

Question 17

What is inspiratory reserve volume?

Answer 17

The maximum amount of additional air that can be taken into the lungs after a normal breath.
You can breath in up to 3000ml of fresh air in addition to the normal tidal volume.
This mainly occurs during exercise.

Question 18

What is expiratory reserve volume?

Answer 18

The amount of additional air that can be breathed out after normal expiration.
This can be up to 1500ml.
After a normal breath the lungs contain the residual volume plus the expiratory reserve volume. If you then exhale as much as possible, only the residual volume remains.

Question 19

What is total lung volume?

Answer 19

Your total lung capacity after you have inhaled as deeply and as much as you can.
It is around 6000ml for an average male.

Question 20

Is inspiration a passive or active process?

Answer 20

Active process as the diaphragm actively contracts causing air to enter the lungs.

Question 21

Is expiration a passive or active process?

Answer 21

Passive process as the diaphragm relaxes to allow air to exit the lungs.

Question 22

What is respiration controlled by?

Answer 22

It is controlled by neurones, cells that conduct nerve impulses, and which are part of the brain stem

Question 23

Neurones in two areas of the medulla oblongata are critical in respiration. What are they?

Answer 23

1)Dorsal respiratory group (DRG)
2)Ventral respiratory group (VRG) - responsible for the rhythm generation that allows rhythmic and continuous breathing

Question 24

Apart from neurones, what other factors control breathing?

Answer 24

The continually changing levels of oxygen and carbon dioxide.

Question 25

What do chemoreceptors do and where are they found?

Answer 25

Chemoreceptors are sensors that respond to chemical fluctuations in the blood. During exercise they detect changes in blood carbon dioxide levels as well as changes in blood acidity, and send signals to the medulla that will make changes in breathing rates.
They are found in the aortic arch and carotid arteries.

Question 26

rank of diagram

Answer 26

inspiratory reserve volume
tidal volume
expiratory volume
residual volume