School Success

### AQA practicals – measuring population size (not combined science)

**Details**:

Measure the population size of a common species in a habitat.

Use sampling techniques to investigate the effect of a factor on the distribution of this species.

**Techniques**:

Use appropriate apparatus to record length and area.

Use transect lines and quadrats to measure distribution of a species.

Safe and ethical use of organisms and response to a factor in the environment.

Application of appropriate sampling techniques to investigate the distribution and abundance of organisms in an ecosystem via direct use in the field.

Use of appropriate techniques in more complex contexts including continuous sampling in an investigation.

**Skills**:

Develop hypotheses regarding distribution of a species as a consequence of a factor.

Plan experiments to test hypotheses on distribution.

Apply a range of techniques, including the use of transects and quadrats, and the measurement of an abiotic factor.

Estimates of population size based on sampling.

Calculate arithmetic means.

Understand principles of sampling.

Understand the terms mean, mode and median as applied to ecological data.

Plot and draw appropriate graphs selecting appropriate scales for the axes.

**Typical questions**

**Videos**