Concept 5.5: nucleic acids store, transmit, and help express hereditary information

what “programs” the amino acid sequence of a polypeptide

genes

what are the two types of nucleic acids

deoxyribonucleic acid (DNA) and ribonucleic acid (RNA)

what does DNA do

provides the directions for its own replication and directs synthesis of messeneger RNA (mRNA) and through mRNA controls protein synthesis

what does RNA do

interacts with the cells protein synthesizing machinery to direct production of polypeptide

what 3 things make up a nucleic acid

a nitrogenous base, a pentose sugar, and one or more phosphate groups

what is the name of the polymer that makes up nucleic acids

polynucleotides

what makes up polynucleotides

nucleotides

what is a nucleotide with no phosphate group

nucleoside

what are the two families of nitrogenous bases called

pyrimidines and purines

what is included in the pyrimidines family

cytosine and thymine and uracil

what is included in the purines

adenine and guanine

what links together a nucleotides

a covalent bond called a phosphodiester linkage

what makes individual genes unique

the sequence of bases along a DNA or mRNA

what occurs when a nucleotide is added

the nucleotide that is being added, provides energy for that bond formation

what is a nucleoside triphosphate

a nucleotide with two additional phosphate groups attached

what form/shape do DNA molecules take

double helix

describe the direction that the backbones of a double helix go

the backbones run in opposite 5’ to 3’ directions from each other in an arrangement called antiparallel

how many bonds from between A and T

2 hydrogen bonds

how many bonds from between C and G

3 hydrogen bonds

what are the two complementary base pairings that will always form

A (adenine) and T (thymine) AND G (guanine) and C (cytosine)

what feature of DNA makes it possible to generate two identical copies of each DNA molecule in a cell preparing to divide

complementary base pairing

is RNA single or double stranded

RNA is single stranded

what is different about the complementary base pairings in RNA

thymine is replaced by uracil, A and U pair

what is the sugar called in DNA

deoxyribose

what is the sugar in RNA

ribose