Final answer:
The first organism in a food chain is always a producer, such as plants and algae, that creates its own food through photosynthesis.
Step-by-step explanation:
In a food chain, the first organism is always a producer. Producers, such as plants and algae, create their own food through the process of photosynthesis. They use sunlight, water, and carbon dioxide to produce glucose and oxygen. This serves as the foundation for the rest of the food chain, as consumers obtain energy by consuming producers or other consumers.
Learn more about Food chain