Unit 5: Carbon, Photosynthesis & Respiration

Introduction:

Unit 5 focuses on the carbon cycle, with emphasis on the exchange of carbon dioxide (CO₂) within plants. Students will grow plants and monitor CO₂ production and consumption. The goals of this unit are for students to be able to explain that growth is the result of plant net uptake of carbon dioxide, and that carbon dioxide production exceeds the levels plants can convert to oxygen. Lab activities will also help students see the potential impacts of carbon dioxide fertilization.

Unit Placement in the Course:

This unit is designed to be taught as part of a sequence with a unit on the nitrogen cycle (Unit 6). While each unit can stand alone, together they provide essential knowledge needed to understand the complex science underlying climate change.

Required Supplies:

CO2 Fertilization of Wheat: (5 weeks of growth time required)

2 1-gallon Containers (recommended: Rubbermaid 6 qt. clear square food storage container-FG630600CLR) with lids
2 milk jugs
Small container (+/- 8 oz.)
Wheat seeds (recommend soaking overnight)
Alka-Seltzer tablets
OPTIONAL:
- CO₂ Sensor
- O₂ Sensor

Photosynthesis vs. Respiration & CO₂ Levels (Plants will need to be about 2 inches tall to get better results, lab works great as a follow up to the CO₂fertilization lab, using the plants grown in that experiment.)