Question 4

The water cycle, photosynthesis, and atmospheric circulation depend directly on energy from the Sun.

These three processes rely on solar energy for their functioning and are crucial components of the Earth's systems.

A) Seafloor spreading

Seafloor spreading is a geological process that occurs at mid-ocean ridges where tectonic plates move apart, creating new oceanic crust. This process is driven by geothermal energy from the Earth’s interior, not by solar energy, making it incorrect in the context of the question.

B) The water cycle

The water cycle is heavily influenced by solar energy, which drives evaporation from bodies of water, leading to condensation and precipitation. This cycle is fundamentally dependent on the Sun's heat to initiate and sustain the movement of water through different states and locations.

C) Photosynthesis

Photosynthesis is the process by which plants, algae, and some bacteria convert light energy from the Sun into chemical energy in the form of glucose. This process is directly reliant on solar energy, making it a key example of how the Sun supports life on Earth.

D) Atmospheric circulation

Atmospheric circulation is driven by the uneven heating of the Earth’s surface by the Sun, which causes wind patterns and weather systems. This process is also directly dependent on solar energy, as it influences temperature and pressure differences that lead to air movement.

Conclusion

The water cycle, photosynthesis, and atmospheric circulation are all processes that directly utilize energy from the Sun. In contrast, seafloor spreading does not rely on solar energy, illustrating why the latter is not included among the correct answers. Understanding these processes highlights the essential role of solar energy in sustaining life and environmental dynamics on Earth.