What are three tasks that DNA must be able to perform in all organisms? Select three answer choices. A. It must store genetic information.

B. It must discard foreign genes.

C. It must instruct cells to produce needed molecules.

D. It must copy itself.

E. It must move to locations throughout the cell.

A. It must store genetic information.

C. It must instruct cells to produce needed molecules.

D. It must copy itself.

Explanation:

Deoxyribonucleic acid, commonly known as DNA, is the genetic material found in virtually all living organisms. It is the biological molecule that holds the genetic instructions needed for the synthesis of useful products (proteins).

DNA molecule must be able to perform the following tasks in a living organism to be considered the genetic material:

- It must store genetic information: DNA is the storage molecule for genetic information in living cells.

- It must instruct cells to produce needed molecules: DNA must be able to undergo gene expression where it directs the synthesis of the needed molecules like proteins, which it encodes.

- It must copy itself: DNA must be capable of replication i.e. must be able to produce two identical copies of itself.

step 1: initiation

initiation is the beginning of transcription. it occurs when the enzyme rna polymerase binds to a region of a gene called the promoter. this signals the dna to unwind so the enzyme can ‘‘read’’ the bases in one of the dna strands. the enzyme is now ready to make a strand of mrna with a complementary sequence of bases.

step 2: elongation

elongation is the addition of nucleotides to the mrna strand. rna polymerase reads the unwound dna strand and builds the mrna molecule, using complementary base pairs. there is a brief time during this process when the newly formed rna is bound to the unwound dna. during this process, an adenine (a) in the dna binds to an uracil (u) in the rna.

step 3: termination

termination is the ending of transcription, and occurs when rna polymerase crosses a stop (termination) sequence in the gene. the mrna strand is complete, and it detaches from dna.