As limestone rock is weathered, it releases carbon dioxide into the air. This carbon dioxide can be taken in by plants and converted into sugars during photosynthesis. Which of Earth’s spheres are interacting above?
a) Atmosphere, geosphere, hydrosphere
b) Biosphere, cryosphere, geosphere
c) Hydrosphere, atmosphere, biosphere
d) Geosphere, atmosphere, biosphere
The Correct answer and Explanation is:
The correct answer is d) Geosphere, atmosphere, biosphere.
In the given scenario, three of Earth’s spheres are interacting: the geosphere, atmosphere, and biosphere. Here’s how these interactions occur:
- Geosphere: The geosphere consists of Earth’s solid features, including rocks, minerals, and landforms. Limestone is a sedimentary rock, and as it weathers, it releases carbon dioxide (CO₂). This process often occurs through chemical weathering, where the minerals in limestone react with water and acids, breaking down the rock and releasing CO₂.
- Atmosphere: The atmosphere is the layer of gases surrounding Earth. When limestone weathers and releases CO₂, this gas enters the atmosphere, contributing to the overall levels of carbon dioxide. CO₂ is one of the critical gases in Earth’s carbon cycle and is vital for processes like photosynthesis.
- Biosphere: The biosphere includes all living organisms, such as plants, animals, and microorganisms. In this case, plants in the biosphere take in carbon dioxide from the atmosphere through photosynthesis. During this process, plants use CO₂, water, and sunlight to produce sugars (glucose), which serve as an energy source for growth and development.
The weathering of limestone demonstrates an important interaction between these spheres. The geosphere releases carbon dioxide, which moves into the atmosphere. Plants (part of the biosphere) then absorb the carbon dioxide to create energy through photosynthesis. This interaction is part of Earth’s broader carbon cycle, which helps regulate carbon levels and maintain balance across the planet’s systems.
Thus, the geosphere, atmosphere, and biosphere are intricately connected in this process, making d) Geosphere, atmosphere, biosphere the correct answer.