Fieldwork and sampling techniquesIB MYP Biology: Mind map

Exam questions on Fieldwork and sampling techniques

1. Students in Dubai are estimating the number of daisies on a rectangular school field that measures 40 m by 25 m. They used a 1 m² quadrat at five positions and counted 4, 7, 5, 6 and 3 daisies.
   Calculate the estimated number of daisies on the whole field.2 marks
2. A researcher is estimating the number of ground beetles in an olive grove in Crete. In the first sample she caught 40 beetles, marked each with a tiny spot of non-toxic paint and released them. A week later she caught 36 beetles, and 9 of them carried a paint spot.
   Calculate the estimated number of ground beetles in the olive grove.2 marks
3. Students studied a coastal sand dune in Portugal. They laid a 50 m tape from the shoreline inland and used a 1 m² grid quadrat every 10 m, estimating by eye the percentage of the ground covered by marram grass. The cover was 5% at 0 m, 15% at 10 m, 35% at 20 m, 60% at 30 m, 80% at 40 m and 90% at 50 m. They used one transect and the same student estimated every quadrat.
   Describe the trend in the cover of marram grass moving inland and give one reason why a transect was suitable for this study.3 marks