dna is a biological polymer used for both information storage and transmission. it is made of four simple building blocks call nitrogen bases, yet these four building blocks provide the information necessary to build any and all organisms. nucleic acids are made up of smaller subunits called nucleotides. the parts of a dna nucleotide include deoxyribose, a phosphate group, and a nitrogen base. dna has four nitrogen bases: adenine (a), guanine (g), cytosine (c), and thymine (t). in dna, nucleotides combine to form two long chains similar to a ladder that has twisted into a spiral or a double helix. the two strands of nucleotides are held together by hydrogen bonds between the nitrogen-containing bases. the hydrogen bonding in dna allows for only certain base pairings: adenine bonds with thymine (a-t), and guanine bonds with cytosine (g-c). dna carries information in a triplet code; each sequence of three nucleotides codes either for a particular amino acid, or indicates the beginning or end of a sequence.

during mitosis or meiosis, dna replicates itself, or makes exact copies using the specific base pairings. the dna code is used for protein synthesis as well. the dna code is carried out in the nucleus via mrna. the transcribed code is taken to the ribosome where translation takes place and the dna code is translated into specific proteins. this process, overall, is referred to as central dogma.

choose all of the correct statements concerning dna, rna, and protein synthesis.

to ensure genetic continuity during cellular growth and repair, dna makes exact copies of itself through replication.
in the nucleus, the cell copies the dna blueprint to mrna during the process of transcription.
the dna code is used to create proteins via the process of transport.
in the dna template, adenine always pairs with uracil.
represents the backbone of information transmission, central dogma.
both dna and rna are composed of subunits called nucleotides.