Final answer:
The Earth's ability to sustain life depends on several factors such as appropriate temperature and pressure, presence of water, and a robust biosphere. If one or two of these were lost, life might not be sustainable in its current form, but some adaptability may allow it to continue in a different state. However, human-induced changes threaten these life-supporting systems and may jeopardize Earth's habitability.
Step-by-step explanation:
The Earth's ability to sustain life is contingent upon several critical factors including an appropriate range of temperature and pressure, the presence of water, and a biosphere capable of planet-scale changes. If one or two of these properties were removed, life as we know it could significantly change or cease altogether. These factors contribute to the regulation of our climate, create habitats for diverse organisms, and provide the necessary elements for life, such as oxygen and nutrients.
Life on Earth has adapted to specific conditions presented by our planet's distance from the sun, its atmosphere, and its hydrosphere. Should these conditions change drastically due to the loss of one or two elements, life may become unsustainable. However, life on Earth is adaptable, and it is possible that some forms of life might persist or even evolve under altered conditions, although they would likely be drastically different from those we are familiar with.
Recent human activity, particularly the emission of greenhouse gases like carbon dioxide, is altering these critical systems, and the habitability of Earth may be at risk. This underscores the importance of caring for our planet and mitigating human impacts that compromise the delicate balance necessary for life.