Abacterial operon is responsible for the production of the biosynthetic enzymes needed to make the hypothetical amino acid tisophane (tis). the operon is regulated by a separate gene, r. the deletion of r causes the loss of enzyme synthesis. in the wild-type condition, when tis is present, no enzymes are made; in the absence of tis, the enzymes are made. mutations in the operator gene (o−) result in repression regardless of the presence of tis.

The tubes transporting minerals and water upward are called ?

What best explains whether bromine (br) or neon (ne) is more likely to form a covalent bond? bromine forms covalent bonds because it has seven valence electrons, but neon has eight valence electrons and already fulfills the octet rule. bromine forms covalent bonds because it has many electron shells, but neon has only two electron shells and is tightly bound to its electrons. neon forms covalent bonds because it can share its valence electrons, but bromine has seven valence electrons and can gain only one more electron. neon forms covalent bonds because it has only two electron shells, but bromine has many electron shells and will lose electrons in order to fulfill the octet rule.

Natural resources are any materials that humans obtain from the earth to meet our wants and needs.