An alpha-helix in a globular protein is found to have a Phe at every fourth position along the length of the helix. The other amino acids are a mix of polar, charged, and nonpolar. Where is this helix most likely located with respect to the rest of the protein molecule

The helix will be located at the cysteine amino acid molecule

Explanation:

The alpha helix is one of the protein arrangement that exist. The protein structure comes in three categories:

The primary structure The secondary structure The tertiary structure quartenary structure

The primary structure consists of an alpha helix. The alpha helix has a kink or bend every four amino acids in the chain. This is because of the amino acid cysteine that has a phenyl group. The phenyl group contributes to the out-of-shape configuration. Hence the bend.