Final answer:
Animal cells obtain energy from glucose derived from photosynthesis, and use ATP for cellular processes. Cells convert glucose into ATP during cellular respiration, which is fundamental for life on Earth.
Step-by-step explanation:
Animal cells derive energy from the products of photosynthesis, mainly in the form of glucose. Therefore, photosynthesis provides fuel for all living organisms. Organisms mainly use glucose and ATP for energy. Glucose is the compact, stable form of energy that is carried in the blood and taken up by cells, whereas ATP contains less energy and is used to power cellular processes. While plants and certain other organisms produce glucose through photosynthesis using sunlight, animals must obtain it through their diet.
The energy stored in the bonds of glucose molecules is released and converted into ATP during cellular respiration, allowing cells to perform work, such as movement and growth. Ultimately, almost all the energy that fuels life on Earth can be traced back to photosynthesis, demonstrating the importance of this process in the flow of energy through ecosystems.