In Mitochondria, Cristae act as sites for

Options

A. protein systhess / translation
B. oxidation - reduction reactions
C. breakdown of molecules
D. phosphorylation of molecules

Answer

**Step-by-Step Solution:**

1. **Understanding Mitochondria Structure**: Mitochondria are double-membraned organelles found in eukaryotic cells. They have an outer membrane and a highly folded inner membrane, which forms structures known as cristae.

2. **Function of Cristae**: The cristae increase the surface area of the inner mitochondrial membrane. This is crucial because it houses various proteins and complexes involved in cellular respiration.

3. **Role in Cellular Respiration**: The primary function of the cristae is to facilitate the electron transport chain (ETC) and chemiosmosis, which are essential processes in cellular respiration.

4. **Oxidation-Reduction Reactions**: During cellular respiration, electrons are transferred through a series of protein complexes in the ETC. This process involves oxidation-reduction (redox) reactions, where electrons are passed from one molecule to another.

5. **ATP Production**: The energy released from these oxidation-reduction reactions is used to pump protons (H+) into the intermembrane space, creating a proton gradient. This gradient drives ATP synthesis through a process called oxidative phosphorylation.

6. **Conclusion**: Therefore, the cristae of mitochondria act as sites for oxidation-reduction reactions, which are critical for ATP production during cellular respiration.

**Final Answer**: In mitochondria, cristae act as sites for oxidation-reduction reactions.

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