The tac promoter, an artificial promoter made from portions of the trp and lacUV5 promoters, has been introduced into a plasmid. It is a hybrid of the lac and trp (tryptophan) promoters, containing the −35 region of one and the −10 region of the other. This promoter directs transcription initiation more efficiently than either the trp or lac promoters. Why? Match the words in the left column to the appropriate blanks in the sentences on the right.

reason is that it uses the -35 region of the trp promoter and -10 region of the lacUV5 promotor, the tac promotor more closely resembles the consensus -35 and -10 sequences than either trp or lac. Tac has 12 out of 12 identiies with the consensus sequences, whereas lac and trp have 9.

Tac promotor is a synthetic, 2hybrid promoter widely used in E.coli for protein production in E.coli using the same induction and repression systems of lac promotor.

Explanation:

answer:

the water molecules are transferred from the roots to the stem or top parts of the tall tree because of important properties of water which are adhesion, cohesion and capillary action. cohesion is the property of water molecules keeps water molecules in a combined state by sharing of bonds between them at the atomic level. adhesion allows the interaction of water molecules with other substances or substrate. adhesion will cause the attachment of water molecules to the wall of the vessel (xylem) of the plant. capillary action occurs when the adhesive force to the vessel wall is stronger than the cohesive force between water molecules. capillary action mimics the transfer of water from a tube or pipe. in this way water utilizes its property to transfer water from down to top level of the plant.