Producers are the source of energy in a food chain.
Explanation:
Producers, through the process of photosynthesis, make their own food. When a primary consumer eats the producer, they get the energy stored by the producer. When a secondary consumer eats the primary consumer, the energy is transferred again.
<span>The muscle at the end of the esophagus is not able to close, which allows stomach acid and digested food to go back up into the esophagus. </span>
