Mechanics Of Breathing

Question 1

Show the correct passage of air:

Answer 1

1. Air is inhaled through the nose
2. It then travels down the pharynx
3. through to the larynx
4. Then into the trachea
5. Then into the Bronchi
6. Then split into the bronchioles
7. And finally into the alveoli

Question 2

Mechanics of breathing during rest/exercise

Answer 2

Breathing at rest changes from breathing during exercise:

• during inhalation at rest, the muscles that are used are the diaphragm and intercostal muscles as the rip cage expands causing the muscles to contract.
• The muscles that are used during exercise when inhaling all the diaphragm, external intercostals, Sternocleidomastoid, scalene and pectorals minor.
• When expiring, the intercostal and abdominal muscles contract, reducing the size of the chest so more air leaves the lungs from a high to low pressure

Question 3

Where is your sternocleidomastoid muscle

Answer 3

It is the big muscle at the back of your neck. They contract during exercise.

Question 4

Gassiest exchange and diffusion

Answer 4

Oxygen defuses from a high concentration from the alveolus to a low concentration in the blood capillary. Oxygen will diffuse from the alveoli into the blood capillaries until the pressure is equal in both

Question 5

Describe the process of diffusion that occurs in the lungs and name the features that assist gaseous exchange/diffusion

Answer 5

Diffusion is the movement of particles from a high concentration to low concentration in the lungs. Gassiest exchange is assisted by the alveoli having a large surface area, moist thin walls (being one cell think) and they have a large blood supply.

Question 6

The lung volumes

Answer 6

• taking air into the lungs is inspiration and moving out is expiration.
• at rest we inspire and expire approximately 0.5l of air

Question 7

Number of breaths (per min) x tidal volume = minute ventilation

Answer 7

.

Question 8

Define tidal volume

Answer 8

-volume of air breathed in or out per breath

Question 9

Define inspiratory reserve volume

Answer 9

• volume of air that can be forcibly inspired after normal breath

Question 10

Define expiratory reserve volume

Answer 10

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

Question 11

Define residual volume

Answer 11

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

The amount of air that stays in your lungs after exhaling as hard as you can so that your lungs don’t stick together

Question 12

Define minute ventilation

Answer 12

-The volume of air inhaled or exhaled from the lungs per minute

Question 13

The effects of exercise on minute ventilation

Answer 13

• minute ventilation is the volume of air inhaled or exhaled from the lungs per minute
• as you would expect, the more demanding the physical activity is, the more breathing increases to meet the extra oxygen demand
• someone’s minute ventilation increases as the intensity of exercise increases

Question 14

Effects of exercise on volumes

Answer 14

• tidal volume: increases during exercise
• inspiratory reserve volume: decreases during exercise
• expiratory reserve volume: slight decrease during exercise
• Residual volume: remains the same ALWAYS
• minute ventilation: BIG INCREASE