The main difference between homologous structures and vestigial structures is that homologous structures are the similar anatomical structures inherited from a common ancestor whereas vestigial structures are the anatomical structures which have reduced their size as they are no longer used.
Sweat evaporates, it is through the process of evaporation that heat is taken away from the body and into the surrounding atmosphere
Nucleus,mitochondria and cytoplasts
Enzymes are proteins that control the speed of chemical reactions in your body. Without enzymes, these reactions would take place too slowly to keep you alive. Some enzymes, like the ones in your gut, break down large molecules into smaller ones.