AP BIOLOGY Viruses, bacteria, prions & DNA Technology Chapters 18-20 Review.

AP BIOLOGYViruses, bacteria,

prions & DNA Technology

Chapters 18-20 Review

Process in which bacteria pick up and incorporate DNA from an outside source

transformationSmall extra-chromosomal DNArings found in bacteria that often carry antibiotic resistancegenes plasmids

Process in which a virus transfers host DNA along with viral DNA to a new bacterial cell

transductionWhat does PCR stand for?

Polymerase chain reactionExplain the difference between

euchromatin and heterochromatin.Heterochromatin: densely packed

Euchromatin: loosely packed

When do inducible operons start operating?

When particles of the substrate are present

The protein coat on the outside ofa virus is called the __________capsid

What is the other type of operon? When does it start working?

Repressible operon; when particles of the substrate disappear

Process in which bacteria with F+ plasmids form a pilus and directly transfer DNA to another bacteria

conjugation

______viruses contain RNA ratherthan DNA

Retro

Viruses that infect bacteriaare called ______________bacteriophages

Name the type ofviral lifecycle shown

lytic

Binary fission

Enzymes found naturally in bacteria which leave “sticky ends”when they cut DNA

Restriction endonucleases(restriction enzymes)

Type of cell division by whichprokaryotes reproduce

Tell some processes that result ingenetic variability in bacteria

Mutation, transformation, Transduction, conjugation,transposons

What does GFP stand for?Green fluorescent protein

Enzyme that joins the “sticky ends” of restriction fragments together

DNA ligaseEnzyme found in retroviruses thatcan produce DNA from RNA

Reverse transcriptase

Give an example of some kinds of genesoften found on plasmids

Antibiotic resistance & fertility

Name the four types of genomes that a virus can consist of.Single-stranded RNASingle-stranded DNADouble-stranded RNADouble-stranded DNA

In both eukaryotes and prokaryotes, gene expression is primarily regulated at the level of ________________transcription

Tell some ways you learned about that could be used to select or identify bacteria that contain a recombinant plasmid.

Putting gene of choice on plasmid which alsocontains genes for antibiotic resistancewill allow bacteria with recombinant plasmids to grow on media with antibiotics.

Putting gene of choice on plasmid which alsocontains GFP will allow bacteria with recombinant plasmids to glow under UV light

DNA has a __________ charge. positive negative

negative

Histones have a __________ charge. positive negative

positive

Bacteriophage DNA that have become integrated into the host cell chromosome are called _________________prophages

Type of viral lifecycle in which the viral DNA is incorporated into the bacterial genome as a prophage and does not kill the

host cell

lysogenic

Tell the functional group foundin DNA that results in it having a negative charge

phosphate

In the bead and string model of chromatin, what are the beads? The string?

Beads: nucleosomesString: linker DNA

Name thisprocess usedto makebillions ofcopies of asmall amountof DNA

PCRPolymeraseChain Reaction

Tell two ways you learned aboutthat could be used to clone a gene

1. Make it into a recombinant plasmid, incorporated it in a bacteria, and letbacteria reproduce2. PCRProteins that are covalently bonded to carbs are called _____________ Glycoproteins

True or False: Plasmids are essential to every bacterium; that’s why all bacteria have them

FALSEWhere in viruses do we find glycoproteins?Attached to the envelope

What is the role of operons?Help control gene expression

Which size fragments move the farthest along the gel duringgel electrophoresis?

Smallest fragments move the farthest

Why are viruses called obligate parasites?

They need a host to survive

Name the two components of all viruses.

Genome (DNA or RNA)Capsid

Transduction Transformation Conjugation Lytic Cycle Lysogenic Cycle

_____________________: replicates phage genome without destroying the host

_____________________: replicates phage genome, but breaks open the host to release new phages, ultimately destroying it

_____________________: alteration of genotype and phenotype by the uptake of foreign DNA from the environment

_____________________: direct transfer of genetic material from one bacterial cell to other; one-way transfer

_____________________: phages carry genes from one host cell to another, and the host cell’s DNA is incorporated into the new host cell’s genome

Transduction

Conjugation

Transformation

Lytic Cycle

Lysogenic Cycle

What effect does DNA methylation have on gene expression?

What effect does histone acetylation have on gene expression?

Methylated DNA is usually not transcribed, so the genes found in that area will not be expressed

Histone acetylation causes the chromatin to spread out, so the genes found in that area will be transcribed and expressed

Restriction enzymes Gene cloning DNA ligase Gel electrophoresis

___________________________: cut up DNA at restriction sites

___________________________: separates nucleic acids based on size and electric charge

_____________________: fuses together pieces of DNA

_____________________: methods that make multiple copies of a DNA segment

Gene cloningDNA ligase

Gel electrophoresisRestriction enzymes

State the main difference between gram-positive and gram-negative bacteria.

Gram-positive: simple cell walls with lots of peptidoglycan

Gram-negative: more complex cell walls with outer layer of lipopolysaccharides

True or False: Operons are found in prokaryotic cells only. TRUE

DNA methylation and histone acetylation are two examples of __________________Epigenetics

Sex pilus Capsule Endospore Cell wall Flagellum

_____________________: helps a prokaryote move towards or away from a stimulus

_____________________: sticky layer of protein that allows prokaryotes to stick to a substrate or to form colonies

_____________________: link prokaryotes during conjugation

_____________________: helps maintain cell shape, provides physical protection, and prevents cell from bursting in hypotonic environment

_____________________: resistant cells that can withstand harsh conditions; chromosome copied and water removed from cell

Endospore

Cell wallSex pilus

Capsule

Flagellum