How Hairy is a Population of Radish Plants?
Variation in traits can be measured. A graph gives us a picture that describes the trait variation collectively within a population.
Students observe and measure the hairiness trait in a population of radish plants. They count hairs on close-up photographs of individual plant petioles and record their data. The class creates a graph to summarize class data and use the graph to describe what it tells us about the distribution of hairiness trait variants in this population.
Materials to Have Ready
For each student:
Notebook page 8
2 radish photos from the class set. There are 49 photos in the set, so this number is intended for a ~25 person class. If you have a smaller class, distribute the photos as evenly as possible. Some or all students may get more than 2
2 sticky notes to record the number of hairs observed on each radish plant photo
For each small group:
A selection of live plant material selected because the leaves and stems are "hairy"
For the class:
A graph template (see lesson plan)