Human Gas Exchange Practical

Question 1

How do you investigate the effect of exercise on breathing rate

Answer 1

Sit still for 5 mins

1 min count the number of breaths u take

Four mins of exercise

Count breathes for a minute

Repeat 3 times for an average

Keep temp constant using air con

Use stopwatch to time urself

Question 2

Why dose breathing rate increase during excersies

Answer 2

Muscles respire mor

Need to be supplied with more O2 and have more CO2 removed

Question 3

Explain the experiment

Answer 3

Limewater is a colourless solution which turns cloudy white in the presence of carbon dioxide

Set up two boilong tubes

Put moutth around the mouthpeice and breath in and out sevberal times

Breathing in: boiling tube A will remain colourless are the air that is drwan in from the room contains very little carbon dioxide

Breathing out: Exhale bubbles through the limewater in B. Contains CO2 produced in respiration so the limewater will turn cloudy white