Test 2 Lecture Phys

Front 1

Prokaryotic Cells

Back 1

Pro=Before
Karyon= Kernel

(Bacteria)

Front 2

Prokaryotic Cells

Kingdom _________

Back 2

Monera

No true nucleus, Genetic material is in "nucleoid" region

Front 3

Prokaryotic cells

No _______________ cells

Back 3

membrane

Front 4

Prokaryotic Cell structure

Back 4

Glycocalyx
Capsule (Slime layer): A layer of gelatinous material covering the cell.

Composition varies with species:
Plypeptides, polysaccharides, Glycoprotein

Front 5

Glycocalyx Capsule (slime layer)

Functions:

Back 5

1) adhesion-to surfaces
2)Osmotic barriers
3)Protect bacteria from Phagocytosis
4)Storage of nutrient

Front 6

Flagella (pl) Flagellum (s)

Back 6

Locomotion/motility

(Know how to draw all forms)

Front 7

Fimbriae and Pili (pl) Pilus (s)

Back 7

Small hair-like projections

1)Sexual conjugation-Pili form tubes for transfer of genetic material.

2) Surface adhesion

3) Bacteriophage receptors (Some viruses attach to pili)

Front 8

Cell Wall

Back 8

1) Maintains the shape of the cell
2) Physcial Protection-
3) Enables the cell to escape rupture (lysis) in a hypotonic environment Lattice/Net like structure.

consists of peptidoglycan

Front 9

Gram + structure

Back 9

many layers of peptidoglycan. forms a thick ridged structure. contain teichoic acid.

Front 10

Gram - Structure

Back 10

Thin layer of peptidoglycan. Looser lattice (less rigid cell wall). High lipid content. No teichoic acid.

Front 11

Plasma membrane

Back 11

1) Regulates diffusion in and out of the cell
2)Contains active transport system
3)Site of enzymes involved in ATP production.

Front 12

Fluid Mosaic Model

Back 12

Phospholipid bilayer

A "dynamic" arrangement of phospholipids and proteins

Front 13

Chromatophores:

Back 13

Contain chlorophyll only found in photosynthetic bacteria.

Front 14

The nuclear material:

Back 14

1 chromosome (DNA) loose in the cytoplasm in the nucleoid region. Bacteria often contain small circular, double-stranded DNA molecules called plasmids.

Front 15

Ribosomes

Back 15

Granules scattered throughout the cytoplasm

Assemble amino acids into polypeptides (protein synthesis)

Front 16

Cytoplamic inclusions:

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Accumulated stored materials

1) Metachromatic granules (Volutin) Stored form of phosphate

2)polysaccharide granules
3)lipid inclusions

Front 17

magnetosomes:

Back 17

Inclusions of iron oxide. act like magnets. May protect cells from accumulation of hydrogen peroxide

Front 18

Endospores:

Back 18

Highly resistant structure. Produced by certain bacteria. All members of the family Bacillaceae Produce endospores.

E. g. Bacillus and Clostridium

Resistance: -The most resistant of all living cells.

Highly resistant to: -Desiccation (Dried out), heat and toxic chemicals. Low metabolic activity (dormant)

Low water content. - Thick spore coat

Heat resistant chemicals (calcium and dipicolinic acid)

formation of endospores: Not a reproductive process. Vegetative cell forms a single spore. germinates to form one vegetative cell

Front 19

Eukaryotic cells

Back 19

(Eu =Good Karyon= Kernal)

Front 20

eukaryotic Cell

Kingdoms

Back 20

Protista, plantae, fungi, animaila

True nucleus containing genetic material. contain membrane bound organells

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Cystoskeleton:

Back 21

network of fibers that form a dynamic framework fo support and movement.

Microfilaments/Actin filaments

Intermediate filaments

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microtubules:

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Form: cilia, flagella and centrioles

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Organelles:

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Specialzed structures that perform specific functions. sequester reactions.

Many contain folded membranes (increase surface area)

Front 24

Nucleus

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spherical or Oval
contains DNA

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Nuclear Envelope/Membrane

Back 25

Double membrane perforated by pores. Maintains nuclear shape and regulates transport in and out of the nucleus.

Front 26

Nucleolus:

Back 26

One or more spherical bodies within the nuclear envelope.

Functions in the synthesis of ribosomal RNA

Front 27

Endoplamic Reticulum (ER)

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Rough ER: Studded w/ ribosomes. site for synthesis of secretory proteins and membrane molecule

*Macromolecules*

Smooth ER- Lack ribosomes synthesizes: Phospholipids, fats and steroids.

*Macromolecules*

Front 28

ribosomes:

Back 28

Formed of 2 subunits : 60S and 40S.

Free ribosomes: suspended in the cytoplasm

Bound ribosomes: attached to ER

sites of protein synthesis

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Golgi Apparatus:

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Flattened sacs, stacked on one another. receive and Modify products from the ER. Packages products in vesicles; Transport, Secretory, and Storage.

LYSOSOMES: Membrane- enclosed sac of hydrolytic enzymes.

function in phagocytosis, recycling cells own organic material

Programed cell destruction.

Front 30

Lysosomal storage disease:

Back 30

Lysosomes lack one of the hydrolytic enzymes

e.g Tay-sachs disease: Lacke enzyme to digest lipid. Excess lipid accumulates and damages brain cells

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Mitochondria:

Back 31

"Power House of the Cell"

Inner membranes folds into cristae sites of cellular respiration (ATP production)

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Plasma Membrane (Fluid Mosaic model)

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Semipermeable/ Selectively permeable. controls what enters and leaves the cell.

Maintains the cells "Homeostasis" (Homo=same Stasis= standing)

Keeps the internal chemical composition within narrow limits.

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transport

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The movement of materials across the plasma membrane.

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Passive Transport:

Back 34

Does not require (ATP Energy) from the cell.

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Simple Diffusion

Back 35

molecules move from an area of greater concentration to an area of lesser concentration.

Front 36

facilitated diffusion:

Back 36

A carrier protein combines with a specific substance and moves it across the membrane.

Front 37

Osmosis:

Back 37

The diffusion of water through a semi-permeable membrane.

Water moves from a higher to a lower concentration of water

Water moves toward a region of higher solute (dissolved substance) concentration.

Front 38

Osmoregulation

Back 38

the control of water balance

Front 39

isotonic

Back 39

iso- same
tonic-tension

concentration of dissolved substances are the same inside and outside the cell. No net flow of water

Front 40

hypertonic:

Back 40

Hyper-above

More solute concentration

Front 41

Hypotonic

Back 41

Low solute conc.

Front 42

Plasmoptysis

Back 42

(osmotic lysis) Bursting of a cell in a hypotonic solution

Front 43

Plasmoptysis

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shrinkage of the cytoplasm due to loss of water in a hypertonic solution

Front 44

channel proteins:

Back 44

Portiens which form channels through the membrane allowing passage of certain molecules.

(Gated channels: some can act as "gates" that open and close)

Front 45

Active Transport

Back 45

Can move substances against their concentration gradient.

Requires that the cell expend energy (ATP)
e.g. Sodium-Potassium pump

Front 46

Endocytosis

Back 46

1)Phagocytosis (cell eating)
2)Pinocytosis (cell drinking)
3) Receptor- Mediated Endocytosis (way most viruses enter human cells

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Exocytosis

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Vacuole fuses w/ plasma membrane & expels contents from cell.

Front 48

Charles chamberland

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Porcelain filters used to filter (remove) bacteria

Front 49

Dmitri Ivanovsky

Back 49

Some filtrates remained infectious???

Front 50

Martinus Beijerinck

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"Contagium vivium fluidium" contagious living fluid

Later coined the name virus (meaning Poison or venom)

Prior to 1930's: Lack of technology needed to : isolate, propagate, observe and analyze was not available.

Front 51

Wendell Stanley

Back 51

Crystallized the first virus (TMV) Consisted of Protein and RNA
viruses first observed w/ and electron microscope

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Mendels Particles:

Back 52

Gregor Mendel

Certain inherited traits seem to be passed from parent to offspring as discrete hereditary "particles"

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Hershey and chase

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genetic material of some viruses was DNA

Front 54

General Characteristics and structure of viruses

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Contain a single type of nucleic acid, either DNA or RNA

Contain a protein coat (Capsid) around the nucleic Acid

Consists of protein subunits called capsomeres

Is Antigenic/Immunogenic (stimulates antibody production

Front 55

some viruses have a/an

Back 55

envelope around the protein coat.

Front 56

Multiply inside living cells

Back 56

(viruses can't synthesize proteins or generate ATP

Front 57

Viruses take over

Back 57

the metabolic activity of host cells

Front 58

Important for clinical control:

Back 58

Difficult to disrupt viral replication w/out interfiering w/ host cell funciton

Front 59

virus size

Back 59

Most only seen w/ an electron microscope (20-1400 nm)

Front 60

virus Shapes

Back 60

helical/spiral

Icosahedral (20 sided polyhedron) Enveloped; complex

Front 61

Environmental Effects on Viruses

Back 61

A. Heat: most are destroyed by > 60 degrees C
B. Cold: little effect (survive -76 degrees c over 1 yr
c. Desiccation: Tolerated drying
D.pH: tolerates pH ~5-9
E. Disinfectants: most are ineffective Alcohol can destroy lipid enveloped viruses

Front 62

Oxidizing

Back 62

agents are most effective
e.g. Hyrogen peroxide, cholorine, iodine

f. UV light damages nucleic acid

Front 63

Classification: Based on:

(viruses)

Back 63

1) Type of nucleic acid (DNA or RNA)
2) Strategy for replication
3) Morphology

Front 64

Cultivation of Viruses (reguires _________

Back 64

Living cells

1)living animals and plants
2)embryonated eggs: Virus is injected into embryonic tissues and membranes
3)Tissue/Cell culture: Cells in solution that provides : nutrients, proper osmotic pressure, pH etc
Primary cell and embryonic diploid cell lines: Grow for a short time in vitro
Continuous/immortal cell lines: Can be maintained I virto indefinitely
4) Bacterial Culture

Front 65

T-even Bacteriphage Lytic Cycle

Back 65

1)Attachment/Adsorption
2)Penetration
3)Biosynthesis
4)Maturation/Assembly
5)Release/Lysis

Front 66

T-even Bacteriphage Lytic Cycle

Attachment/adsorption

Back 66

Phage tail attach to specific receptors on bacteria

Front 67

T-even Bacteriphage Lytic Cycle

Penetration

Back 67

Phage release enzyme -------> LYSOSOME dissolves part of the bacteria cell wall

Front 68

T-even Bacteriphage Lytic Cycle

Biosynthesis

Back 68

Viral DNA takes over the machinery of the host cell and begins producing viral DNA and structural components

Front 69

T-even Bacteriphage Lytic Cycle

Maturation cycle

Back 69

Phage DNA assembles into complete viruses

Front 70

T-even Bacteriphage Lytic Cycle

Release/Lysis

Back 70

Phage lysosome breaks down bacterial cell wall and multiplied phages are released

Front 71

Burst time

Back 71

the time from adsorption to release. "Burst Size" = the average number of virons released by a cell (50-200 virons for T-Even phage)

Front 72

Lysogenic Cycle

Back 72

Lysogeny: Viral DNA is incorporated into the host DNA without causing lysis of the host cell.

Lysogenic cell: A cell containing a prophage (provirus)
Prophage genes are repressed by a repressor protein.

Latency: Ability to remain in host cells for long periods.

Front 73

Phage conversion:

Back 73

Induction/ Excision: Certain environmental factors may cause a prophage to revert to the lytic cycle.

e.g. UV light or certain chemicals

SPECIALIZED TRANSDUCTION: When a prophage is excised from the host chromosome it can take with it adjacent DNA from the bacterial chromosome.

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Animal viruses

Back 74

Attachment
Penetration occurs by Receptor Mediated endocytosis
uncoating by viral or host cell enzymes
biosynthesis
Maturation and release (Budding)

Front 75

Latent Viral infections

Back 75

Virus remains in asymptomatic host cell for long periods.
Reactivated by: fever, UV light, stress, trauma, hormonal changes, and repair mechanisms in the cell eg cold sores, shingles.

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Wilhelm Ellerman and Olaf Bang

Back 76

Found that leukemia could be transferred to healthy chickens by cell-free filtatres containing viruses

Front 77

F.Peyton Rous

Back 77

Chicken sarcoma (cancer of connective tissue) similary transferred (cell free filtrates containing viruses)

Front 78

oncogenes

Back 78

Genes that cause a normal cell to be transformed into a malignant cell.

Front 79

Michael Bishop and Harold varmus

Back 79

Cancer inducing genes carried by viruses are derived from the animal cells genome.

Front 80

Proto-oncogenes:

Back 80

Normally direct synthesis or products for cell growth and development
When a virus containing a n oncogene is introduced into a cell, the cell may be unable to regulate synthesis of the virus's oncogene. The excess product may result in uncontrolled cell division.

Front 81

Stanley Prusiner

Back 81

Received the nobel prize in Medicing for his work on prions (proteinaceous infectious particles

Front 82

Infections proteins:

Back 82

Inherited and transmissible by ingestion, transplant & surgical instuments.

Front 83

Spongiform encephalopathies

Back 83

sheep scrapie, Creutzfeldt-Jakob Dz, Gerstmann-Staussler-Scheinker syndrome, fatal familial insomnia, mad cow Dz, several others

Front 84

Prion Characteristics

Back 84

Resist to heating
Not sensitive to radiation Tx
Not destroyed by enzymes that digest RNA and DNA
Not sensitive to protein denaturing agents, such as phenol
Shown to move easily from one species to another

Front 85

PrPc:

Back 85

Normal cellular prion protein on cell surface.

Front 86

PrPSc

Back 86

The harmful form:Scrapie protein is believed to result from a mutation in a normal gene fro PrPc, or contact with the altered/harmful for converts the normal protein into harmful form.

Front 87

The harmful PrPsc form accumulates in

Back 87

brain cells forming plaques

Front 88

ana

Back 88

build up

Front 89

cata

Back 89

down

Front 90

tomy

Back 90

to cut

Front 91

hydrogen bonds are broken by

Back 91

heat

Front 92

viruses are species

Back 92

specific

Front 93

Antibiotics

Back 93

Antimicrobial substances produced by microorganisms

Front 94

Major genera of Antibiotics and antimicrobial drugs

Back 94

1)PCN (fungi)
2)Cephalosporium (fungi)
3)Streptomyces (actinomycetes)
4)Micromonospora (Actinomycetes)
5)Bacillus (Gram + Bacteria)

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Bacteriostatic

Back 95

Inhibit the growth of bacteria

Front 96

Bactericidal

Back 96

Kills bacteria

Front 97

Narrow spectrum

Back 97

Affects only a select group of microbes.

Front 98

Broad spectrum

Back 98

Affect large numbers of bacteria (Gm+ and Gm-)

Front 99

Superinfection

Back 99

Overgrowth by a resisant organism

Front 100

Antibiotic and Antimicrobial drug
Modes of Action

Back 100

1)Inhibition of cell wall synthesis
2)Inhibition of protein synth
3)Injury to plas. mem
4)Inhibition of Nucleic acid synth
5)Inhibion oh the synth of essential metabolites

Front 101

mechanisms or resistance to Antibiotic and Antimicrobial drugs

Back 101

1)Ability to destroy the antimicrobial
2)prevent penetration of the antimicrobial
3)Alteration of target structure
4)Active transport (efflux pumps)

Front 102

Antibiotic and Antimicrobial drug

Control of resistance

Back 102

1)Administer effective doses and finish the complete dosage
2)avoid using outdated, weakened antibiotics
3)Eliminate indiscriminate use.
4)Comibined therapy: Two or more antibiotics given simultaneously
SYNERGISTIC: pcn AND streptomyci
AVOID ANTAGONISTIC: PCN and Tetracyclin

combine an antibiotic w/ a b/lactamase inhibitor
Augmenti (Amoxicillin combined w/ potassium clavulanate.)

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catabolism

Back 103

metabolic reactions require enzymes

Front 104

anabolism

Back 104

synthesis of chemiacal compounds requires energy

Front 105

Mechanisms of enzyme action

Enzymes lower "______________"

Back 105

Activation energy

Enzyme structure: Active site: gives the enzyme is specificity

Binds w/ the substrate to form an enzyme-substrate complex. some Enzymes are protein only, others have a protein and a nonprotein portion.

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Protein portion of enzyme

Back 106

apoenzyme

COFACTOR: Nonprotein component
coenzyme: organic cofactor -metallic cofactor

Front 107

apoenzyme + cofactor =

Back 107

holoenzyme (Whole Charge)

Front 108

Enzyme structure

Back 108

"lock and key" fit: enzymes only react w/ a specific substrate.

specificity is due to surface configuration/conformation (shape) of the protein

Conformation is the result of: Primary, secondary, tertiary, quaternary structers.

Front 109

Weak interaction:

Back 109

Hydrogen bonding
ionic bonds
hydrophobic interactions (nonpolar R groups)

Front 110

Covalent Linkage:

Back 110

Disulfide bridges b/w two cyusteine monomers (disulfide bond)
in addition to conformation specificity involves IONIC CHARACTER

Front 111

Factors influencing enzyme activity

Back 111

Enzymes can be denatured by temp and pH
Substrate concentration
competitive inhibition
noncompetitive inhibition
feedback inhibition

*know graphs in book for test*

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Exoenzyme/Extracellular enzymes:

Back 112

function outside the cell.

Front 113

endoenzymes/intracellular enzymes

Back 113

functions inside the cell

Front 114

Genetics

Back 114

The science of heredity. The study of genes:

How they carry info (codes),pass that info on and how is that info expressed

Front 115

genes:

Back 115

The functional units of heredity.
Genes contains the info (codes)for inherited characteristics. Morphology, metabolism, behavior, pathology, etc.

Front 116

genotype

Back 116

the genetic makeup of an organism (the information itself)

Front 117

genome:

Back 117

the total of all genes (genetic information) in a cell.

Front 118

phenotype

Back 118

the physical/external manifestation of the genotype. (the physical traits or appearance)

Front 119

Genes consist of segments of

Back 119

DNA

Front 120

DNA

Back 120

A nucleic acid (repeating units called nucleotides)

Three basic parts:
Base: Adenine,thymine, guanine, cytosine
Sugar: deoxyribose
Phosphate

Front 121

In eukaryotic cells DNA is

Back 121

wound around clusters of histones (chromosomal proteins) DNA is made up of two antiparallel strands joined by hydrogen bonds.

Front 122

DNA replication

Back 122

Enzymes unwind the double helix

Front 123

DNA Polymerase adds

Back 123

new bases to the new DNA strand -DNA replication

Front 124

semiconservative

Back 124

one original and one new strand

Front 125

RNA sugar is

Back 125

ribose

Front 126

Transcription translation
DNA---------------------->mRNA------------------->Protein

Back 126

Transcription translation
DNA---------------------->mRNA------------------->Protein

*just remember this*

Front 127

(RNA & PROTEIN SYNTHESIS)
Transcription:

Back 127

The process of synthesizing messenger RNA (mRNA) from a DNA template

Involves RNA polymerase binding to a promoter
Uracil substitutes for thymine

Front 128

(RNA & PROTEIN SYNTHESIS)

In eukaryotic cells a processing step is needed:

Back 128

Introns are removed and exons are joined together with a cap and tail.

Front 129

(RNA & PROTEIN SYNTHESIS)

Translation

Back 129

The use of a mRNA template in protein synthesis

1. (initiation) mRNA becomes associated with a ribosome

2. (elongation) A series of Transfer RNA's (tRNA) each w/ a specific amino acid attaches to mRNA in the ribosome. Peptide bonds form b/w amino acids.

Each set of 3 bases on mRNA = a codon

Each codon specifies a specific amino acid. tRNA carries the anticodon and the amino acid

3. Termination/stop) a termination or stop codon/signal attaches and the ribosome, mRNA and protein separate.

Front 130

Genetic Transfer
Frederick Griffith

Back 130

Working w/ 2 strains of strep. pneumonia:

Heat killed virulent (w/capsules)+ Live Avirulent (no capsules) --------->Live Virulent (with capsules)

Front 131

genetic transfer

Transformation:

Back 131

the process in which genes are transferred from one bacterial cell to another as "naked" DNA in solution.

Front 132

Genetic Transfer

Mechanism of Transformation:

Back 132

Fragments of DNA from lysed cells are taken up by other bacteria and recombine w/ their own DNA

Front 133

genetic transfer

Conjugation

Back 133

Transfer of genetic information by cell to cell contact

donor (F+) cell attaches to recipient (F-) cells by means of sex pili and transfers genetic material. can transfer plasmids or parts of its own chromosome.

Front 134

genetic transfer

Transduction

Back 134

Transfer of genetic information from one bacteria to another by means of a bacteriophage.

Front 135

Plasmids:

Back 135

small self-replicating circles of DNA found in many bacteria (symbiotic mutualistic relationship)

F plasmid (fertility)/ conjugative plasmid

Front 136

conjugative plasmid

Back 136

carries genes for sex pili and transfer of the plasmid.

Front 137

Dissimilation plasmids

Back 137

Encode enzymes for catabolism of unusual compounds. Eg some pseudomonas can metabolize toluene, camphor and petroleum hydrocarbons. Poss use in bioremediation

Front 138

Bacteriocinogenic Plasmids (Bacteriocins):

Back 138

Proteins which kill other bacteria

Front 139

R Plasmids (Resistance factors)

Back 139

Provide resistance to antibiotics and other chemicals

Front 140

Plasmids for toxin production:

Back 140

eg. Tetanospasmin Staphylococcal enerotoxin

Front 141

Genes for several traits may be

Back 141

coupled together on the same plasmid

Front 142

Transposons

Back 142

Barbara McClintok

"jumping genes" segments of DNA that can move their position in the genome

contain insertion sequences that code for an enzyme for cutting and resealing DNA (transposase)

complex transposons carry other genes in addition to transposase genes.

Front 143

Mutations:

Back 143

Any alterations in the base pair sequence.
(mutation in gametes can be passed on to offspring)

Front 144

spontaneous Mutations:

Back 144

Results from mistakes in replication or natural background radiation= Natural spontaneous

1 mutation/10 (5) - 10 (10) replications

Front 145

induced mutations

Back 145

Mutagens/mutagenic agents: Agents which alter DNA. eg X rays; carcinogens ----Man made

Front 146

Categories of mutations (point mutations)

Back 146

Base pair substitutions

1.Same -sense mutation: codes for the same amino acid

2. Mis-Sense mutation: Codes for a different amino acid eg. sickle cell anemia: CTT= Glutamic acid changed to CAT =Valine
3. Nonsense mutation: codes for a "stop" signal or a stop signal is substituted w/ an amino acid

Front 147

Frameshift Mutation

Back 147

insertions or deletions: results in Mis-Reading of many codons

eg. Deletion THE CAT ATE THE RAT
THC ATA TET HER AT

Front 148

Gene regulation/control

Constitutive Enzymes:

Back 148

Produced constantly (Present at all times) Not subject to repression. Other enzymes are expressed only as needed.

Front 149

Gene regulation/control

Repressible enzymes:

Back 149

subject to repression

Front 150

Gene regulation/control

inducible enzymes

Back 150

produced by the cell only when needed

Front 151

selective expression of genes

Back 151

Operon model
Regulatory gene: codes for a repressor protein
Promoter: Site of RNA polymerase attachment.
Operator gene: acts as a switch. Controls transcription of the structural gene.
Structural gene: codes for the amino acid sequence of a protein.
Repressible Operon: Normally in the "on" mode but is turned off when the gene product is in abundance.

Front 152

the gene product acts as a ___________________

Back 152

Corepressor. The corepressor activates the repressor.

Front 153

translational and Post-Translational control

DNA technology

Biotechnology:

Back 153

The use of microorganisms, cells, or cell components to make a product.

e.g. foods, antibiotics, vitamins, enzymes

Front 154

genetic engineering:

Back 154

The manipulation of genetic material for practical purposes.

Front 155

selection and mutation

Artificial selection:

Back 155

Breed/culture a naturally-occurring organism/ microbe that produces desired product.

Front 156

Mutation:

Back 156

Mutagens cause mutations that might result in a microbe w/ a desired trait.

Front 157

site directed mutagenesis:

Back 157

change a specific DNA code to change a protein

Front 158

Recombinant DNA technology:

Back 158

Techiques for recombining genes from different sources in vitro and transferring this recombinant DNA into a cell where it may be expressed. Allows genes to be moved across species barriers.

Front 159

Recombinant DNA Technology

Overcomes natural barriers

Back 159

Anatomical, molecular, physical appearance, behavioral, molecular

Front 160

Recombinant DNA Technology


Restriction Enzymes

Back 160

Discovered In bacteria
Destroy Bacteriophage DNA and DNA picked up in transformation in bacterial cells.
Cannot digest (host) DNA because of methylated cytosines.
Recognize short, specific nucleotide sequences.

Front 161

Recongition sequences:

Back 161

"Symmetrical" sequences 4-8 nucleotides running in opposite directions.
Palindromes: e.g. GAATTC on one strand and CTTAAG on the other.
R. Enz. cut between the same adjacent nucleotides on both strands.

Results in "RESTRICTION FRAGMENTS"
double-stranded DNA w/ single -stranded ends. "sticky ends"
THese sticky ends are used to join DNA from different sources.
These unions are temporary (held by hydrogen bonds)
Can be made permanent by adding DNA LIGASE
Outcome; A DNA molecule carrying a new combination of genes.

Front 162

Gel Electrophoresis:

Back 162

Separtes molecules based on size and electrical change.
Used to separate restriction fragments
Isolate and purify individual fragments
Band patterns used in DNA fingerprinting

Front 163

Vectors

Back 163

Carry new DNA to desired cell.
Shuttle vectors can move cloned DNA amoung several different species.
Plasmids and viruses can be used as vectros. (Recombined DNA molecules are useful only if they can be made to replicate)

Front 164

Gene Libraries

Back 164

Gene Libraries are made of Pieces of an entire genome stored in plasmids or phages

*cDNA* is made from mRNA by reverse transcriptase

DNA can be inserted into a cell by: Transfromation, Electroporation, Protoplast fusion, Microinjection; Gene gun

Front 165

PCR (polymerase chain reaction)

Back 165

Amplifies DNA
Extremely small samples of DNA can be multiplied to high concentration.
Used to:
clone DNA for recombination
Amplify DNA to detectable levels
Sequence DNA
Diagnose genetic disease
Detect pathogens

Front 166

RFLP Analysis:

Back 166

Restriction Fragment Length Polymorphism
Each person has a unique array of RFLPs a "genetic fingerprint"
FORENSIC USE: 1/million chance two people will have matching DAN fingerprints for the few regions tested.

Front 167

Subunit/ Piggyback vaccines:

Back 167

nonpathogenic viruses carrying genes for pathogen's antigens as vaccines

Front 168

Genetic Screening:

Back 168

Diagnosis of genetic disorders.

Front 169

Gene Thereapy

Back 169

to replace defective or missing genes

Front 170

antisense RNA:

Back 170

complementary to normal RNA. Blocks mRNA from directing protein synthesis

Front 171

DNA Probes:

Back 171

Used to detect and identify pathogens in food and pt's.

Front 172

Applications of Genetic Engineering

Back 172

subunit/piggyback vaccines
genetic screening
gene therapy
antisense RNA
DNA Probes

Front 173

Human Genome project:

Back 173

Nucleotides have been sequenced

Front 174

Human Proteome Project

Back 174

May provide diagnostics and tx's

Front 175

Agricultural Uses:

Back 175

Insect and Dz resistance, Herbicide resistance, Retard spoilage, Nitrogen fixation

Front 176

Genetic Engineering
Safety issues and Ethics

Back 176

avoid accidental release
Genetically modified crops must be safe for consumption and for the environment.
Who will have access to an individuals genetic information?