Ch. 12 DNA Technology + The Human Genome

Question 1

Recombinant DNA

Answer 1

DNA that has been genetically modified for variety

Question 2

What are the 3 mechanisms for gene transfer?

Answer 2

1) Transformation
2) Transduction
3) Conjugation

Question 3

Transformation

Answer 3

Taking up DNA from the fluid surrounding a cell

- incorporation of new genes into a cell from DNA that the cell takes up from the fluid around it

Question 4

Transduction

Answer 4

Transfer of bacteria genes by phage virus

• DNA hidden by bacteria
• transfer of bacterial genes from one bacterial cell to another by a phage

Question 5

Conjugation

Answer 5

Union of 2 cells in DNA transfer thru a mating bridge called pilus

• bacterial version of reproduction/mating
• the union (mating) of two bacterial cells or protist cells and the transfer of DNA b/w the two cells

Question 6

What happens once bacterial DNA enters the cell?

Answer 6

It is integrated into the single circular chromosome

• crossing over allows for integration
• results in recombinant DNA

Question 7

F Factor

Answer 7

Piece of DNA that makes conjugation possible

• F = fertilization
• carries genes for proteins of the bridge provides the site for the origin of replication

Question 8

Plasmid

Answer 8

Small circular piece of DNA separate from the chromosome that is transferred in linear form
- found in prokaryotes

Question 9

Vector

Answer 9

Plasma carrying extra genes
- in microbiology, a piece of DNA, usually a plasmid or a viral genome, that is used to move genes from one cell to another

Question 10

R Plasmid

Answer 10

“Resistant”

• carry genes for enzymes that destroy antibiotics
• allows bacteria to transfer to to non-R-plasmid genes
• helps with genetic engineering

A bacterial plasmid that carries genes for enzymes that destroy particular antibiotics, thus making the bacterium resistant to antibiotics

Question 11

How do you customize bacteria?

Answer 11

1) Isolate plasmid from the bacteria
2) Obtain the DNA from a gene of interest
3) Insert desired gene into plasmid = recombinant DNA
4) Bacteria cell takes up the plasmid
5) Genetically engineered bacteria is cloned
6) Regeneration of desired gene
7) Desired genes are removed and introduced to embryos

Question 12

Biotechnology

Answer 12

Using organisms (microbes) to perform practical tasks
- DNA technology

Question 13

Restricted enzymes

Answer 13

Chop up foreign DNA there; restrict DNA from living in bacteria cell

A bacterial enzyme that cuts up foreign DNA, thus protecting bacteria against intruding DNA phages and other organisms; used in DNA technology to cut DNA molecules in reproducible ways

Question 14

Sticky ends

Answer 14

Restriction sites exposed with DNA fragments

Question 15

DNA ligase

Answer 15

Pasting enzyme
- catalyzes the formation of covalent bonds b/w adjacent nucleotides

An enzyme, essential for DNA replication that catalyzes the covalent bonding of adjacent DNA nucleotides; used in genetic engineering to paste a specific piece of DNA containing a gene of interest into a bacterial plasmid or other vector

Question 16

Gene cloning

Answer 16

Production of multiple copies of a gene

Question 17

Human Genome

Answer 17

Collection of all of the genetic material in a human cell

- 100,000 genes

Question 18

Repetitive DNA

Answer 18

Many nucleotide sequences are repeated

Question 19

What is type 1 of repetitive DNA?

Answer 19

Thousands of repetitive nucleotides

• long, near centromeres and tips of chromosomes
• support and structure
• maintains organization

Question 20

What is type 2 of repetitive DNA?

Answer 20

Hundreds of repetitive nucleotides

- short and scattered

Question 21

Transposons “Jumping Genes”

Answer 21

DNA segments that can move b/w chromosomes, change locations

• movement of DNA interrupts other genes
• natural mutagens
• “copy & paste” and “cut & paste”

Question 22

Human Genome Project

Answer 22

International endevor to identify and map genes on chromosomes

Question 23

What are the 3 methods of gene mapping?

Answer 23

1) Genetic (Linkage) mapping
- use data of genetic crosses to determine order of linked genes and relative distance
2) Physical mapping
- use restriction enzymes to break DNA into identifiable fragments that will then overlap
3) DNA Sequencing
- automatic DNA sequencing machines

Question 24

What does mapping help to do?

Answer 24

Help w/ embryonic development, evolution, aging, diagnosis, treatment, prevention of diseases

Question 25

Recombinant DNA Technology

Answer 25

Techniques for synthesizing recombinant DNA in vitro and transferring it into cells, where it can be replicated and may be expressed (genetic engineering)

Question 26

Genomic Library

Answer 26

A set of DNA segments from an organism’s genome; each segment is eerily carried by a plasmid or phage

Question 27

Probe

Answer 27

In DNA technology, a labeled single stranded nucleic acid molecule used to find a specific gene, or other nucleotide sequence, w/in a mass of DNA

Question 28

Gel Electrophoresis

Answer 28

A technique for separating and purifying macromolecules; a mixture of molecules is placed on a gel between a positively charged electrode and a negatively charged on; negative charges on the molecules are attracted to the positive electrode and the molecules migrate toward that electrode; the molecules separate in the gel according to their rates of migration

Question 29

Genetic Marker

Answer 29

An allele tracked in a genetic study; a specific section of DNA that earmarks a particular allele; may contain specific restriction sites (points where restriction enzymes cut the DNA) that occur only in DNA that contains the allele

Question 30

Restriction fragments

Answer 30

Molecules of DNA produced from a longer DNA molecule, cut up by a restriction enzyme; used in RFLP (restriction fragment length polymorphism) analysis, genome mapping, and other applications

Question 31

RFLP (restriction fragment length polymorphism)

Answer 31

Differences in homologous DNA sequences that are reflected in different lengths of restriction fragments produces when the DNA is cut up w/ restriction enzymes
- detects potential harmful alleles

Question 32

Southern Blotting

Answer 32

A technique that reveals the presence of certain nucleotide sequences in a sample of DNA; after gel electrophoresis of the cut up DNA separates the fragments into bands, the DNA fragments are blotted onto a sheet of paper and then tested with a radioactively labeled nucleic acid probe

Question 33

Polymerase Chain Reaction

Answer 33

A technique used to obtain many copies of a DNA molecule or part of a DNA molecule. A small amount of DNA mixed with the enzyme, DNA polymerase, DNA nucleotides, and a few other ingredients, replicates repeatedly in a test tube
- w/o living cells

Question 34

Telomeres

Answer 34

Repetitive DNA at each end of a eukaryotic chromosome

Question 35

DNA Fingerprint

Answer 35

An individual’s unique collection of DNA restriction fragments, deflected by electrophoresis and nucleic acid probes

Question 36

Vaccine

Answer 36

A harmless variant or derivative of a pathogen used to stimulate a host’s organism’s immune system to mount a long term defense against the pathogen

Question 37

Ti Plasmid

Answer 37

Bacterial plasmid that induces tumors in plant cells that it infects’ often used as a vector to introduce new genes into plant cells

Question 38

Transgenic organism

Answer 38

An organism that contains genes from another species

Question 39

Gene therapy

Answer 39

Alteration of afflicted individual’s genes

- could backfire b/x genetic variation needed

Question 40

Eugenics

Answer 40

A socially rejected practice among humans of attempting to eliminate genetic disorders and “undesirable” inherited traits by selective breeding