Unit 1 C

Question 1

Pathway in and out

Answer 1

IN:
Nose & mouth ->Pharynx-> Larynx
-> Trachea-> Bronchus-> Bronchioles-> Alveoli

OUT:
Alveoli-> Bronchioles-> Bronchus-> Trachea -> Larynx-> Pharynx -> Nose & mouth

Question 2

Gaseous Exchange
definition

Answer 2

delivery of oxygen from the lungs to the blood stream and the removal of carbon dioxide from the tissues

Question 3

Exchange of Gas within lungs

Answer 3

1. Air enters body through nose & mouth
2. Passes through to reach alveoli
3. Oxygen diffuses through alveoli into capillaries
4. Haemoglobin in blood becomes oxygenated forming oxyhaemoglobin
5. Oxygen travels to working muscle cells
6. Carbon D travels from working muscles to lungs
7. Carbon D diffuses from the capillaries to the alveoli
8. Air is breathed out through nose and mouth

Question 4

Partial pressure

Answer 4

o2 in the alveoli
vo2 in capillaries

Question 5

Diffusion Gradient

Answer 5

-With exercise theres and increase in diffusion gradient
-More gases are being passed through

Question 6

Mechanics of Breathing

Expiration- Breathing OUT

Answer 6

-External intercostal muscles relax (internal contract), rib cage returns to normal
-Diaphragm relaxes pushing it up
-Chest cavity gets smaller so pressure in lung increases
-Air flows out the lung

Question 7

Mechanics of Breathing

Inspiration- Breathing IN

Answer 7

-External intercostal muscles contract, pulls rib cage up & out
-Diaphragm contracts causing it to flatten
-Chest cavity gets larger causing pressure in lung to fall
-Air moves into the lungs from the higher outside pressure

Question 8

Lung volumes

Answer 8

Inspiratory/Expiratory reserve volume- additional air that can be breathed in and out during exercise
Tidal volume- volume of air breathed in and out with each breath
Residual volume- lungs are never totally empty (unless collapsed lung)
Vital capacity- maximum amount of air that can be forced out
Total lung capacity- TLC after u have inhaled as deeply as you can (6000cm3)

Question 9

Tidal volume stats

Answer 9

-500cm3 air breathed in
-350cm3 reaches the alveoli & gaseous exchange
-150cm3 fills larynx, pharynx, trachea, bronchi and bronchioles

Question 10

Control of Breathing

Brain- Medulla Oblongata

Answer 10

-middle of the brain
-neurones are responsible for breathing
-controls the diaphragm contracting and relaxing through sending impulses/signals to nerve

Question 11

Control of Breathing

Chemical

Answer 11

-Chemoreceptors monitor changin levels of o2 and co2 in the blood
-found in the medulla ,aortic arch and carotid arteries
-Send signals to the medulla that make changes to breathing

Question 12

Responses

Answer 12

Increased breathing rate- increased demandfor o2 and production of co2 stimulates faster deeper breathing, anticipatory rise occurs when exercise begins in prep for demand
Increased tidal volume- allows more air to pass through the lungs to meet the increased demand

Question 13

Adaptations

Answer 13

Increased vital capcity- lung volume increases
Increased strength of respiratory musces- diaphragm & intercostal muscles increase in strength; allows greater expansion of chest cavity
Increased o2 + co2 transfusion rate- able to train harder and for longer, suppy o2 quicker and remove co2 quicker (diffsuion gradient)

Question 14

Additional Factors

Answer 14

Asthma- bands of muscle surrounding the aiway are usually relaxed, asthma makes bands contract/tighten, restricts movement of air in & out
Altitude & Partial pressure- edurance athletes may altitude train when o2 is psread out, o2 diffuses slower as pressure differences reduced.
Over time, lungs become larger and more efficient , body will produce more red blood cells and capillaries, allowing gaseous exchange and transport of o2 more efficient.