Year 13 Biology
Evolution, speciation and populations in ecosystems
Natural selection and evolution, genetic drift, speciation, the effect of environmental factors on populations, interspecific and intraspecific competition, succession and conservation, and estimating population size.
Evolution, speciation and populations in ecosystems free practice
No timer and no account needed. Check each answer as you go, then read the explanation.
1. Quadrat estimate. Plants have a mean density of 6 per square metre in a field of area 500 m². Estimate the total number of plants in the field.
Your answer is marked as soon as you give it.
Want more of this topic?
- A narrated lesson video that works through the topic, with worked examples
- 100 practice questions at foundation, core and stretch level
- A worked explanation on every answer, and progress you can come back to
The lesson and practice open when you start the 7-day free trial. Cancel before it ends and you pay nothing.