Biology Unit 2 Molecular Genetics

Front 1

A virus that infectst bacteria, also called a bacteriophage

Back 1

phage

Front 2

The form of native DNA, referring to its two adjacent polynucleotide strands

Back 2

double helix

Front 3

predicts that when a double helix replicates, each of the two daughter molecules will have one old strand, derived from the parent molecules, and one newly made strand.

Back 3

semiconservative model

Front 4

A Y-shaped point on a replicating DNA molecule where new strands are growing

Back 4

replication fork

Front 5

An enzyme that catalyzes the elongation of new DNA at a replication fork by the addition of nucleotides to the existing chain

Back 5

DNA polymerase

Front 6

A linking enzyme essential for DNA replication; catalyzes the covalent bonding of the 3' end of a new DNA fragment to the 5' end of a growing chain

Back 6

DNA ligase

Front 7

An already existsing RNA chain bound to template DNA to which DNA nucleotides are added during DNA synthesis

Back 7

primer

Front 8

is an enzyme that untwists te double helix at the replication fork, separating the two old strands

Back 8

helicase

Front 9

DNA-cutting enzyme (damaged part of DNA would be cut out)

Back 9

nuclease

Front 10

An enzyme that catalyzes the lenghtening of telomeres; the enzyme includes a molecule of RNA that serves as a template for new telomere segments

Back 10

telomerase

Front 11

The synthesis of RNA on a DNA template

Back 11

transcription

Front 12

The synthesis of a polypeptide using the genetic information encoded in a mRNA molecule. There is a change of language from nucleotides to amino acids

Back 12

translation

Front 13

A three-nucleotide sequence of DNA or mRNA that specifies a particular amino acid or termination signal; the basic unit of the genetic code.

Back 13

codon

Front 14

An enzyme that links together the growing chain of ribonucleotides during transcription.

Back 14

RNA polymerase

Front 15

Within the promoter the TATA box is located about 25 nucleotides upstream from the transcriptional startpoint. RNA polymerase II cannot recognize the TATA box and other landmarks of the promoter on its own. Transcription factors that recognize the TATA box bind to the DNA before RNA polymerase can do so.

Back 15

TATA box

Front 16

A noncoding, intervening sequence within a eukaryotic gene.

Back 16

intron

Front 17

A coding retion of a eukaryotic gene that is expressed. Exons are separated from eachother by introns

Back 17

exon

Front 18

transfer RNA's function is to transfer amino acids from the cytoplasm's amino acid pool to a ribosome. Interpreter of the mRNA molecule.

Back 18

tRNA

Front 19

ribosomal RNA are found in ribosomal subunits along with proteins

Back 19

rRNA

Front 20

A change in a geve at a single nucleotide pair.

Back 20

point mutation

Front 21

A mutation involving the addition of one or more nucleotide pairs to a gene

Back 21

insertion

Front 22

(1) A deficiency in a chromosome resulting from the loss of a fragment through breakage. (2) A mutational loss of a nucleotide from a gene.

Back 22

deletion

Front 23

A chemical or physical agent that interacts with DNA and causes mutation

Back 23

mutagens

Front 24

A mutation occuring when the number of nucleotides inserted or deleted is not a multiple of 3, thus resulting in improper grouping into codons.

Back 24

frameshift mutation

Front 25

An enzyme encoded by some RNA viruses that uses RNA as a template for DNA synthesis.

Back 25

reverse transcriptase

Front 26

The protein shell that encloses the viral genome; rod-shaped, polyhedral, or more completely shaped.

Back 26

capsid

Front 27

A phage genome that has been inserted into a specific site on the bacterial chromosome.

Back 27

prophage

Front 28

A type of viral replication cycle resulting in the release of new phages by death or lysis of the host cell.

Back 28

lytic cycle

Front 29

Viral DNA that inserts into a host genome.

Back 29

provirus

Front 30

an RNA virus that reproduces by transcribing its RNA into DNA and then inserting the DHA into a cellular chromosome; an important class of cancer-causing viruses

Back 30

retrovirus

Front 31

A plant pathogen composed of molecules of naked RNA only several hundred nucleotides long

Back 31

viroid

Front 32

(1) The conversion of a normal animal cell to a canerous cell. (2) A phenomenon in which external DNA is assimilated by a cell.

Back 32

transformation

Front 33

In bacteria, the transfer of DNA between two cells that are temporarily joined.

Back 33

conjugation

Front 34

A unit of genetic function common in bacteria and phages, consisting of coordinately regulated clusters of genes with related functions.

Back 34

operon

Front 35

A protein that suppresses the transcription of a gene

Back 35

repressor