Chapter 13, 14, 15 Test

Lagging strand

Elongates away from replication fork

Sticky end

A single-stranded end of a double-stranded restriction fragment

cAMP

Accumulates when glucose is scarce

Origins of replication

Beginning site of chromosomal replication of DNA

miRNA

Blocks translation by binding to mRNA

Proteasome

Breaks down proteins

Chromatin

Complex of DNA and proteins that makes up eukaryotic chromosomes

TATA box

Crucial to form the transcription initiation complex

Restriction enzyme

Cut DNA molecules at a limited number of specific locations

Leading strand

DNA pol III on template strand and continually adds nucleotides to new complementary strand

Restriction fragments

DNA segment that results from the cutting of DNA

Promoter

DNA sequence where RNA polymerase attaches and initiates transcription

Nuclease

DNA-cutting enzyme

Nucleoid

Dense region of DNA in a bacterium

Beadle and Tatum

Determined function of gene is to dictate the production of a specific enzyme

Alternative RNA splicing

Different mRNA molecules are produced from same primary transcript

Chargaff

Discovered 1:1 ratio of bases?

Hershey and Chase

Discovered DNA is genetic material of phage

Watson and Crick

Discovered shape of DNA?

Fred Griffith

Discovered transformation of DNA

Mismatch repair

Enzymes remove and replace incorrectly paired nucleotides resulting from replication errors

Helicase

Enzymes that untwist the double helix at replication forks

General transcription factors

Essential for transcription of all protein-coding genes

Lac operon

Example of inducible operon

Trp operon

Example of repressible operon

E site

Exit site

Differential gene expression

Expression of different genes by cells with the same genome

Topoisomerase

Helps relieve strain in double helix by breaking, swiveling, and rejoining DNA strands

Heterochromatin

Highly condensed chromatin that generally doesn't transcribe

P site

Holds the tRNA carrying the growing polypeptide chain

A site

Holds the tRNA carrying the next amino acid to be added to chain

Inducer binds to active repressor

How to flip switch for inducible operon

Corepressor binds to inactive repressor protein

How to flip switch for repressible operon

DNA ligase

Joins Okazaki fragments together

Single-stranded binding proteins

Keeps unpaired DNA strands from re-pairing

High

Lactose present, glucose absent cAMP level?

Low

Lactose present, glucose present cAMP level?

Spliceosome

Large complex made of proteins and small RNAs that remove introns

Euchromatin

Less condensed form of chromatin available for transcription

DNA methylation

Long term gene inactivation Ex: Barr bodies

Ubiquitin

Marks proteins for degredation

Transcription factors

Mediate binding of RNA polymerase and the initiation of transcription

Recombinant DNA molecule

Molecule containing DNA from two different sources

rRNA

Most abundant type of RNA

Introns

Noncoding segments of nucleic acid that lie between coding regions

Inducible

Operon that is off but needs to be turned on

Repressible

Operon that is on but needs to be turned off

RNA polymerase

Pries two strands of DNA apart and joins together RNA nucleotides complementary to the DNA template strand

Histone acetylation

Promote transcription

A & G

Purines?

T & C

Pyrimidines?

DNA polymerase I

Removes RNA primers from the fragments and replaces it with the required nucleotides.

Living R bacteria transformed into pathogenic S bacteria

Results of Griffith's experiment

R strand

Rough & harmless

Terminator

Sequence that signals end of transcription

RNA primer

Short stretch of RNA with a 3' end and elongated with DNA nucleotides

Nucleus

Site of transcription

Ribosomes

Site of translation

Plasmids

Small circular DNA molecules that are replicated separately

S strand

Smooth & pathogenic

Restriction site

Specific sequence on a DNA strand that is recognized and cut by a restriction enzyme

AUG

Start codon

UAA UAG UGA

Stop codon

Transcription

Synthesis of RNA using information in DNA

Translation

Synthesis of polypeptide using the information of mRNA

Lagging strand

Synthesized discontinuously in series of Okazaki fragments

RNA primase

Synthesizes RNA primer

Polymerase chain reaction

Technique for amplifying DNA

tRNA

Transfer amino acids from the cytoplasmic pool of amino acids to a growing polypeptide in a ribosome

Semiconservative Model

Two strands of the parental molecule separate and each function as a template for synthesis of a new complementary strand

Gel electrophorisis

Used to separate and visualize restriction fragments

Phage

Viruses that infect bacteria

Franklin

Who produced DNA photo that showed width/spacing and double helix?

Replication fork

Y-shaped region where the parental strands of DNA are unwound

DNA polymerase III

essential for the replication of the leading and the lagging strands