PreScreener: The Carbon Cycle

Task 1: Molecule Identification

Identify the molecule below as either an input or output of Photosynthesis and Cellular Respiration.

1. Glucose (C6H12O6)
   • Photosynthesis: ______
   • Cellular Respiration: ______
2. Carbon Dioxide (CO2)
   • Photosynthesis: ______
   • Cellular Respiration: ______

Task 2: System Interactions

Read the scenario below and answer the question.

A massive wildfire burns through a forest in California. The trees (biosphere) are combusted, releasing their stored carbon into the air (atmosphere).

Which of the following describes this event’s impact on the carbon cycle? A) The event moves carbon from a sink to a source. B) The total amount of carbon on Earth increased because of the fire. C) The event represents a flux of carbon from the biosphere to the atmosphere. D) Oxygen levels in the atmosphere will increase as a result.

Task 3: Graph Literacy

Look at a standard “Keeling Curve” graph (Atmospheric CO2 over time).

• What does the general slope of the line tell us about the current state of Earth’s carbon budget? Is it in equilibrium?

(Space for student response)