Unit B

Module 3 ~ Lesson 1

Leaf Size Investigation

Abiotic conditions in the environment affect biotic components in the environment. You will examine the effects of different abiotic conditions on the morphology of plant leaves. The leaves on plants in two different locations with different abiotic conditions will be studied. The purpose of this lab is to determine if different abiotic conditions affect a plant's morphology.

Outdoor Option


If the season permits and leaves are measurable on the trees, you will need a ruler, a chart for recording your data, and access to plants of the same species in two different areas.

  1. Choose trees or bushes in two different locations that have different abiotic conditions (for example, a tree near a lake compared to one in a meadow or a tree by a road compared to a tree in a forested area).

  2. Make a prediction. Do you expect to see any differences in the length of the leaves between the two trees?

  3. In the data table, describe the abiotic factors and the location of each tree to the best of your ability.

  4. Measure and record the lengths of 10 leaves from each tree. Record your observations on this document. 

  5. Calculate the average leaf length for each tree.


Alternate

  1. View the images for location 1 and location 2 shown below.

  2. Make a prediction about the leaf sizes in each location. Do you expect to see any differences in the length of the leaves between the two trees?

  3. Open the data table and describe the abiotic factors of each location to the best of your ability.
  4. Calculate the average leaf length for each tree provided in the data table.


Location 1

Location 2

Calculations and Questions

Answer the Analysis questions found on page 80 of your text and then check your work.

Self-Check

The abiotic conditions will vary depending on the location you have chosen. Light, temperature, moisture, and soil type are a few abiotic components that will have an effect.
The leaf sizes could be affected if the microclimates are different enough, but if the areas are too much alike, then there may not be a noticeable difference.
Extra moisture, sunlight, or soil in an area may increase the size of the leaves. Your answers will vary.