Amide group is present in

Options

A. Lipids
B. Carbohydrates
C. Amino acids
D. Proteins

Explanation

To determine where the amide group is present, we can follow these steps:

### Step 1: Understand the Amide Group
The amide group is characterized by the functional group -C(=O)NH2 (or -C(=O)NR2, where R can be hydrogen or hydrocarbon groups). It consists of a carbonyl group (C=O) linked to a nitrogen atom (N).

### Step 2: Identify Biological Molecules
In biological chemistry, we need to identify which biomolecules contain the amide group. The most common biomolecules include proteins, carbohydrates, lipids, and nucleic acids.

### Step 3: Focus on Proteins
Proteins are polymers made up of amino acids. Each amino acid contains an amine group (-NH2) and a carboxylic acid group (-COOH). When amino acids link together to form proteins, they undergo a condensation reaction to form peptide bonds, which are a type of amide bond.

### Step 4: Confirm the Presence of Amide Group in Proteins
The peptide bond formed between the amino group of one amino acid and the carboxyl group of another amino acid results in the formation of an amide bond. Thus, proteins are indeed composed of chains of amino acids linked by amide (peptide) bonds.

### Conclusion
Therefore, the amide group is present in proteins.

### Final Answer
The amide group is present in proteins.

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