Some cats will lick Vaseline off a spoon. Or, if you smear it on the cat's nose or front leg below the elbow, she'll lick it off. Some cats will also eat Vaseline mixed into tuna.ome cats will lick Vaseline off a spoon. Or, if you smear it on the cat's nose or front leg below the elbow, she'll lick it off. Some cats will also eat Vaseline mixed into tuna.
Concept 17 A gene is made of DNA. In the 1920s, experiments showed that a harmless strain of bacteria can become infectious when mixed with a virulent strain of bacteria that had been killed. The dead bacteria apparently provide some chemical that transforms the harmless bacteria to infectious ones.
Proteins are made of a chain of 20 different types of amino acid molecules. This chain folds up into a compact shape, rather like an untidy ball of string. The shape of the protein is determined by the sequence of amino acids along its chain and it is this shape that, in turn, determines what the protein does.n addition to inheritance, genetics studies how genes are turned on and off to control what substances are made in a cell-gene expression; and how a cell divides-mitosis or meiosis. Some phenotypic traits can be seen, such as eye color while others can only be detected, such as blood type or intelligence.