Observe the relationship between the first two words and then fill in the suitable word at the fourth place :
mitochondria : cristae : : chloroplast : ………

Explanation

To solve the analogy question: "mitochondria : cristae : : chloroplast : ………", we need to identify the relationship between the first two words and apply that relationship to the second pair.

1. **Identify the first pair**: The first word is "mitochondria" and the second word is "cristae".
- Mitochondria are organelles in cells that are responsible for energy production. They have structures called cristae, which are the folds of the inner membrane that increase the surface area for biochemical reactions.

2. **Identify the second pair**: The first word in the second pair is "chloroplast".
- Chloroplasts are the organelles in plant cells that conduct photosynthesis.

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