a student is setting up a model to study the carbon cycle and natural sources of carbon dioxide. they create a microenvironment that contains soil, leaf debris, an earthworm, heterotrophic bacteria, and a sun lamp. what natural source of carbon dioxide and major metabolic process was left out of the model?
What natural source of carbon dioxide and major metabolic process was left out of the model?
Answer:
In the model described, the student has included many components relevant to the carbon cycle, such as soil, leaf debris, an earthworm, heterotrophic bacteria, and a sun lamp. However, two crucial natural sources of carbon dioxide and major metabolic processes were left out of the model:
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Plants and Photosynthesis: One major natural source of carbon dioxide that was left out of the model is plants. Plants play a vital role in the carbon cycle through the process of photosynthesis. During photosynthesis, plants absorb carbon dioxide from the atmosphere and convert it into glucose and oxygen using sunlight. In this model, the absence of plants excludes a significant carbon dioxide sink and a key metabolic process.
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Respiration: Another fundamental metabolic process that was left out of the model is respiration. Both plants and heterotrophic bacteria respire, releasing carbon dioxide back into the atmosphere. Respiration is the process by which organisms break down organic compounds to release energy for cellular activities. This overlooked process is critical in the carbon cycle as it releases carbon dioxide back into the environment.
Including plants and considering the role of respiration in the model would provide a more comprehensive understanding of the carbon cycle and the exchange of carbon dioxide between different components of the ecosystem.