The sum total of the process by which an animal or a plant takes in and utilizes food sub stances is known as _________ .

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for the term that describes the total processes by which an animal or plant takes in and utilizes food substances.

2. **Identifying Key Concepts**: The key concepts here are "taking in food" and "utilizing food substances". This relates to how organisms obtain and use nutrients.

3. **Defining the Term**: The process that encompasses all these activities is known as "nutrition". Nutrition includes the intake of food, its digestion, absorption, transport, utilization for energy, and eventual excretion of waste.

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