.................... is cofactor in enzyme cytochrome oxidase,

Explanation

To solve the question ".................... is cofactor in enzyme cytochrome oxidase," we need to identify the cofactor associated with the enzyme cytochrome oxidase. Here’s a step-by-step solution:

### Step 1: Understand the Role of Cytochrome Oxidase
Cytochrome oxidase is an enzyme that plays a crucial role in the electron transport chain, which is part of cellular respiration. It is located in the inner mitochondrial membrane and is responsible for the final step of the electron transport chain.

**Hint:** Remember that cytochrome oxidase is involved in energy production and is part of the electron transport chain.

### Step 2: Identify the Components of Cytochrome Oxidase
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