Biotechnology

Question 1

Biotechnology

Answer 1

The use of microorganisms, cells, or cell components to make a product (foods, antibiotics, vitamins, emzymes )

Question 2

Recombinant DNA technology (rDNA)

Answer 2

The insertion or modification of genes to produce desired proteins

Question 3

Clone

Answer 3

Population of genetically identical cells arising from one cell; each carries the vector

Question 4

Selection

Answer 4

Selecting for a naturally occuring microbe that produces a desired product

Question 5

Mutation

Answer 5

Mutagens cause mutations that might result in a microbe with a desirable trait

Question 6

Site-directed mutagenesis

Answer 6

A targeted and specific change in a gene

Question 7

Restriction enzymes

Answer 7

• Cut specific sequences of DNA
• Destroy bacteriophage DNA in bacterial cells
• Methylated cytosines in bacteria protect their own DNA from digestion
• create blunt ends or staggered cuts known as sticky ends

Question 8

Vectors

Answer 8

• Carry new DNA to desired cells
• Must be able to self-replicate (ori-origin of replication)
• Plasmids and viruses can be used as vectors

Question 9

Shuttle vector

Answer 9

Exist in several different species and can move cloned sequences among various organisms

Question 10

What is the Polymerase Chain Reaction (PCR)

Answer 10

The process of increasing small quantities (amplifying) of DNA for analysis

• Used for diagnostic tests for genetic diseases and detecting pathogens
• Reverse transcription PCR uses mRNA as template

Question 11

What are the steps of the polymerase chain reaction -PCR

Answer 11

1. Incubate target bacteria at 94 dc for 1 min; this temp will separate the strands (hydrogen bonds break)
2. Add primers, nucleotides, and DNA polymerase
3. Incubate at 60 dc for 1 min; this allows primers to attach to single-stranded DNA
4. Incubate at 72 dc for 1 min; DNA polymerase copies the target DNA at this temperature
   Second cycle- repeat the cycle of heating and cooling to make two more copies of target DNA
   *Denature-Anneal-Extension

Question 12

Transformation

Answer 12

Cells take up DNA from the surrounding environment

Question 13

Electroporation

Answer 13

Electrical current forms pores in cell membranes

Question 14

Protoplast fusion

Answer 14

Removing cell walls from two bacteria; allows them to fuse

Question 15

Gene gun

Answer 15

Most frequently used on plant cells to insert foreign DNA

Question 16

Microinjection

Answer 16

Small needle used to inject DNA (mostly animal cells)

Question 17

What are genomic libraries?

Answer 17

Collections of clones containing different DNA fragments

• An organism’s DNA is digested and spliced into plasmid or phage vectors and introduced into bacteria
• At least one clone exists for every gene in the organism

Question 18

What is cDNA?

Answer 18

Complementary DNA is made from mRNA by reverse transcriptase

• Used for obtaining eukaryotic genes because eukaryotic DNA has introns that do not code for protein.
• mRNA has the introns removed, coding only for the protein product

Question 19

Blue-white screening for selecting clones

Answer 19

Uses plasmid vector containing ampicillin resistance gene (amp^R) and B-galactosidase gene lacZ

• Bacteria is grown in media containing ampicillin and x-gal, a substrate for B-galactosidase.
• Only the the bacteria that picked up the plasmid will grow in the presence of ampicillin/ Bacteria that hydrolyze x-gal produce galactose and in indigo compound. The indigo turns the colonies blue; The bacteria that cannot hydrolyze x-gal produce white colonies

Question 20

Colony hybridization for selecting clones

Answer 20

Use DNA probes (short segments of single-stranded DNA complementary to the desired gene.

Question 21

List the advantages and disadvantages of using E. coli for genetic engineering

Answer 21

Advantages- Easily grown and its genomics are known

Disadvantages- Produces endotoxins and does not secrete its protein products

Question 22

List the advantages and disadvantages of using Saccharomyces cerevisiae (eukaryotic yeast) for genetic engineering

Answer 22

• Easily grown and has a larger genome than bacteria

- Expresses eukaryotic genes easily

Question 23

List the advantages and disadvantages of using Plant cells and whole plants for genetic engineering

Answer 23

• Express eukaryotic genes easily

- Plants are easily grown, large-scale, and low cost

Question 24

List the advantages and disadvantages of using mammalian cells for genetic engineering

Answer 24

Advantages-Express eukaryotic genes easily
-Can make products for medical use
Disadvantages- Harder to grow

Question 25

Subunit vaccines

Answer 25

Made from pathogen proteins in genetically modified yeasts

Question 26

DNA vaccines

Answer 26

-Non pathogenic viruses carrying genes for pathogen's antigens (Not approved for human use)

Question 27

Gene therapy

Answer 27

To replace defective or missing genes

Question 28

Gene silencing (SiRNA)

Answer 28

Small interfering RNAs (SiRNAs) bind to mRNA, which is then destroyed by RNA-induced silencing complex (RISC)

Question 29

Gene silencing process

Answer 29

1. An abnormal gene, cancer gene, or virus gene is transcribed in a host cell 2. SiRNA binds mRNA 3. RISC breaks down the RNA complex 4. No protein expression occurs

Question 30

RNA interference (RNAi)

Answer 30

Inserts DNA encoding siRNA into a plasmid and transferred into a cell

Question 31

Shotgun sequencing

Answer 31

Sequences small pieces of genomes which are assembled by a computer

Question 32

Metagenomics

Answer 32

The study of genetic material directly from environmental samples (i.e. soil)

Question 33

The Human Genome Project

Answer 33

Sequenced the entire human genome

Question 34

The Human Proteome Project

Answer 34

Will map proteins expressed in human cells

Question 35

Bioinformatics

Answer 35

Understanding gene function via computer- assisted analysis

Question 36

Proteomics

Answer 36

Determining proteins expressed in a cell

Question 37

Reverse genetics

Answer 37

Discovering gene function from a genetic sequence

Question 38

Southern blotting

Answer 38

DNA probes detect specific DNA in fragments (RFLPs) separated by gel electrophoresis

Question 39

Northern blotting

Answer 39

DNA probes used to identify RNA

Question 40

DNA fingerprinting

Answer 40

Used to identify pathogens-PCR microarrays and DNA chips can screen samples for multiple pathogens -Differs from medicine because it requires proper collection of evidence and establishing a chain of custody

Question 41

Nanotechnology

Answer 41

Bacteria can make molecule-sized particles - Nanospheres used in drug targeting and delivery - Lipid nanoparticles used to deliver the mRNA in the moderna and Pfizer covid-19 vaccines

Question 42

Ti Plasmid

Answer 42

Occurs in Agrobacterium tumefaciens - Integrates into the plant genome and causes a tumor-like growth - Can be used to introduce rDNA into a plant

Question 43

What are some of the agricultural applications of rDNA

Answer 43

``` B+ toxin Herbicide resistance Suppression of genes-antisense DNA Nutrition Human proteins ```

Question 44

Identify some of the safety and ethical issues using DNA technology

Answer 44

- Need to avoid accidental release into the environment - Genetically modified crops must be safe for consumption and for the environment - Who will have access to an individual's genetic information?