0610/62
Question
2(c)
Cambridge IGCSE – Mark Scheme
PUBLISHED
Answer
Marks
6
independent variable:
1 at least three different temperatures used ;
Guidance Heart answers
Independent variable:
1) At least three exercise intensities
method:
2 method of maintaining the different temperatures ;
3 moist medium for growing seeds described e.g. soil / cotton
wool / agar ;
4 large number of seeds at each temperature / two or more
further repeats (of entire experiment) ;
Method:
2) Method of controling or differentiating intensity
3) Suitably fit subject.
4) Large number of subjects/Two or more further
repeats.
dependent variable:
5 count the number of seeds germinated after a particular
time / measure time taken for seeds to germinate ;
6 observation of germination described ;
dependent variable:
Measure heart rate immediately after exercise
5) Measure time taken for heart rate to return to
normal.
6) Observation of heart rate (method, location,
beats)
variables kept constant:
7, 8 and 9 any three from: ;;
volume of water (used) / humidity
pH
variety of (tomato) seed / age of seeds
oxygen (concentration)
type of soil or growing medium / AW
Variable kept constant:
7, 8 and 9 any three from: ;;
Subject at rest/resting pulse rate before excercise
Terrain/environmental conditions
Time of day (as relating to not being tired yet
Duration of exercise
Age of subject.
other:
10 relevant safety precaution ;
© UCLES 2021
March 2021
Other:
10) Relevant safety precaution
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