KS3 Science - Unit 7D
Variation and classification
There are two sections to this unit: first investigating variation within species (both genetic and environmental), and second considering the ways in which animals and plants can be classified. As there is no restriction on the habitats chosen, it is possible to carry out this work in the school grounds and local area.
1. Environmental variation in sun and shade | 2. How can living organisms be sorted into groups?
Follow the links to read more about each investigation, and to download Teacher Guidance and Pupil Sheets for each.
1. Environmental variation in sun and shade
The leaves of many common plants show environmental variation between 'sun leaves' and 'shade leaves'. To allow differentiation by task, this topic has been split into three full investigations, using the leaves of stinging nettles and beech.
(a) Environmental variation in beech trees
(Levels 4-5)
A full investigation. Pupils sample sun and shade leaves of beech and use these to compare leaf area and internode length. Results are displayed on a bar chart.
(b) Environmental variation in beech trees
(Levels 5-6)
A full investigation. Pupils sample sun and shade leaves of stinging nettles and use these to compare leaf colour and leaf thickness. More advanced practical skills are required. Results are displayed on a bar chart and frequency graph.
(c) Environmental variation in stinging nettles
(Levels 5-6)
A full investigation. Pupils sample sun and shade leaves of stinging nettles and use these to compare leaf area and the time taken for leaves to begin wilting. Results are displayed on bar charts.
2. How can living organisms be sorted into groups?
Pupils use fresh plant material to construct a key to leaves and shoots. To allow differentiation by task, this topic has been split into two full investigations.
(a) Constructing a key for tree leaves and shoots
(Levels 4-5)
A full investigation. Pupils use a small number of tree leaves and shoots to help them to identify and evaluate the characters which are most useful for devising a key.
(b) Constructing a key for tree leaves and shoots
(Levels 5-6)
A full investigation. Pupils use a small number of tree leaves and shoots to help them to identify and evaluate the characters which are most useful for devising a key.
