Explain the three pathways of breakdown in living organisms.

Explanation

### Step-by-Step Solution:

1. **Introduction to Breakdown Pathways**:
- Living organisms break down glucose through three main pathways: glycolysis, aerobic respiration, and anaerobic respiration.

2. **Glycolysis**:
- The first step in the breakdown of glucose occurs in the cytoplasm of the cell, where glucose (a 6-carbon molecule) is converted into pyruvate (a 3-carbon molecule). This process is known as glycolysis and is common to all organisms.

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