Water
Purpose
- To demonstrate water is essential for plant growth.
- To learn that water is only one of many limiting factors of
plant growth.
Overview
The class will grow maize plants with different availabilities of water
and evaluate how the level of watering influences plant growth.
Students will observe plant growth and record the period it takes for a
given water supply to be consumed. Results will be assessed by
comparing plant size and weight. The experiment will also
demonstrate that a decrease of water in the experimental system is
caused by both plant consumption and by evaporation directly from the
surface of substrate.
Essential Questions
How is water a limiting factor to plant growth?
Sub-Questions
Are the plants able to grow without water?
Why do plants need water for growth?
How much water a plant body contain?
How can we measure the water content in the plant body?
Student Outcomes
- Students will understand how to formulate a reasonable hypothesis
- Students will know how to set up a simple biological experiment using maize plants
- Students will gain skills in scientific observation
- Students will learn to interpret experimental results
Science Concepts
- Formulating hypotehsis
- Testing hypothesis with experiment
- Planning and perfomrance of the experiment
- Presentation of the results and their interpretation
Time
Approximate total amount of time necessary for the experiment is 20-24
days. There can be slight variation in duration of each part of the
experiment due to differences in local conditions.
- Germination:
- Preparation for seed germination 1-2 class periods
- During germination, water daily and record germination progress– 10 minutes per day for 7 days.
- Cultivation:
- Preparation of the experimental system and planting 1-2 class periods
- During cultivation, water daily and record plants growth factors- 10 minutes per day for 11 days.
- Harvest:
- Preparation of the plants for drying 1 class period
- Drying:
- Place plants in drying oven for 8-12 hours at 90°C
- Evaluation/Interpretation:
- Record final results, review hypothesis, answer essential questions 1-2 class periods