Biol 1411 Test 2-2

Front 1

differential activation of genes

Back 1

The underlying process of cell differentiation.

Front 2

DNA

Back 2

Info storage molucule

Front 3

gene

Back 3

In DNA, a sequence of nucleotides which contains information necessary for the metabolism and structure of an organism.

Front 4

recombinant DNA

Back 4

DNA constructed from pieces of DNA from several sources, either through crossing-over in meiosis or laboratory manipulation.

Front 5

nucleosome

Back 5

A nuclear particle composed of histones with DNA wrapped around them; a basic aspect of chromosome structure.

Front 6

codon

Back 6

In mRNA, a set of three nucleotides that specifies an amino acid to be incorporated into a protein.

Front 7

start codon

Back 7

In messenger RNA, a set of three nucleotides that indicates the beginning of information for protein synthesis.

Front 8

stop codon

Back 8

In messenger RNA, a set of three nucleotides that indicates the end of information for protein synthesis.

Front 9

degenerate code

Back 9

In the genetic code, many amino acids are coded by several codons, not just one each.

Front 10

promoter region

Back 10

That portion of a gene in which control molecules and RNA polymerases bind during gene activation and transcription.

Front 11

TATA box

Back 11

In the promoter region of many genes, a region rich in thymine- and adenine-containing nucleotides, believed important for RNA polymerase binding.

Front 12

RNA polymerase II

Back 12

The enzyme responsible for transcribing genes into messenger RNA.

Front 13

enhancer elements

Back 13

Regions of DNA upstream from the structural region of a gene, which increase the ability of RNA polymerases to transcribe the gene.

Front 14

exons

Back 14

Those portions of the structural region of a gene whose information is actually translated into protein.

Front 15

intron

Back 15

A portion of the structural region of a gene whose information is not translated into protein; instead, the these portions of the hnRNA are removed and digested.

Front 16

transcription

Back 16

The "reading" of DNA by RNA polymerase with the simultaneous production of RNA.

Front 17

hnRNA

Back 17

Heterogeneous nuclear RNA.

Front 18

transfer RNA (tRNA)

Back 18

Ribonucleic acids that carry amino acids to ribosomes during protein synthesis.

Front 19

anticodon

Back 19

In transfer RNA, the nucleotide triplet complementary to the codon of mRNA.

Front 20

translation

Back 20

In protein synthesis, the utilization of mRNA to guide the incorporation of amino acids into protein.

Front 21

messenger RNA (mRNA)

Back 21

Molecule which carries genetic information from DNA to the site of protein synthesis.

Front 22

frameshift error

Back 22

During the translation of mRNA, a misalignment of the ribosome such that the triplets it reads are not true codons.

Front 23

trans-acting factor

Back 23

Molecules that affect the activity of a gene but which are not part of the DNA strand that contains the gene; they must diffuse to the DNA from some other location in a cell.

Front 24

microRNA

Back 24

General term for any of several types of RNA that are extremely short (a few dozen nucleotides or less) and appear to be involved in controlling gene expression.

Front 25

DNA melting (denaturation)

Back 25

Heating a DNA double helix gently until the hydrogen bonds are broken and one molecule separates from the complementary molecule.

Front 26

DNA hybridization

Back 26

The slow cooling of a mixture of short DNA molecules such that complementary strands encounter each other and hydrogen bond into double helices.

Front 27

restriction endonucleases

Back 27

Enzymes that recognize specific sites in DNA double helices, then cut the two strands in complementary sites.

Front 28

DNA ligase

Back 28

An enzyme that can attach two strands of DNA to each other, repairing nicks and linking Okazaki fragments into complete molecules of DNA.

Front 29

reverse transcriptase

Back 29

An enzyme that catalyzes the synthesis of DNA, using RNA as a template.

Front 30

DNA cloning

Back 30

Producing large numbers of identical copies of DNA, usually by inserting it into bacteria and allowing the bacteria to multiply.

Front 31

plasmid

Back 31

A small circule of DNA occurring in some bacteria and acting like a bacterial chromosome.

Front 32

open reading frame (ORF)

Back 32

A sequence of DNA that has many components of a gene (promoter, transcription start and end sites, exon/intron boundaries) but which is not actually known to act as a gene.

Front 33

retrovirus

Back 33

A virus whose genetic material is single-stranded RNA; the most common type of plant virus.

Front 34

bacteriophage

Back 34

A virus that attacks bacteria.

Front 35

temperate virus

Back 35

A virus whose genome has been incorporated into the host's genome, being replicated simultaneously with host DNA; the virus produces few or no symptoms.