The tracking of people by trayned dogs is based on the recognition Which Compounds in a sweat from feat?

The tracking of people by trained dogs is based on the recognition of specific compounds in the sweat from feet. These compounds include:

1. Fatty acids: Sweat contains a variety of fatty acids, which are produced by the sebaceous glands. These fatty acids give sweat its characteristic odor and can be used by dogs to track a person's scent.

2. Proteins: Sweat also contains proteins, which are shed by the skin cells. These proteins can contain DNA, which can be used to identify a person.

3. Volatile organic compounds (VOCs): Sweat also contains a variety of VOCs, which are small molecules that are released into the air. These VOCs can include acetone, ethanol, and isoprene, which can all be used by dogs to track a person's scent.

Dogs have a highly developed sense of smell and can detect these compounds even in very small amounts. This allows them to track a person's scent even if they have been gone for a long time.