The main steps of nutrition in humans are ______,_____,_____,_____, and _______ .

Explanation

To answer the question about the main steps of nutrition in humans, we can break it down into five key processes:

1. **Ingestion**: This is the first step where food is taken into the body. It involves the act of eating and drinking, allowing nutrients to enter the digestive system.

2. **Digestion**: In this step, the ingested food is broken down into simpler substances. This process involves both mechanical and chemical breakdown, converting large, complex food molecules into smaller, absorbable units.

3. **Absorption**: After digestion, the simpler substances are absorbed into the bloodstream. This occurs primarily in the small intestine, where the nutrients pass through the intestinal walls and enter the circulatory system.

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