exam 4 (ch 19-21) Flashcards
(61 cards)
1
Q
- Makes copies of DNA
- Can copy DNA when the original source is limited or impure
- Selective of specific sequences
A
PCR (polymerase chain reaction)
2
Q
- Allows us to separate molecules of various sizes
- DNA can move between the gel molecules
- *Electrical current is used to move molecules
- *Smaller molecules are carried further
- DNA forms distinct bands that can be cut out and sequenced
A
Gel Electrophoresis
3
Q
- Instead of relying on chain termination, the single template strand is immobilized and electronic sensors can tell which nucleotide (C, T, A, or G) is added to the strand
- Allows for faster and cheaper processing
- What do we do with the sequences?
- *Compare species’ characteristics
- *Look for mutations that lead to disease
A
DNA Sequencing
4
Q
Genetically identical descendants of a cell or animal
A
Clones
5
Q
DNA from 2 different sources (often different sources)
A
Recombinant DNA
6
Q
Contain DNA that might be necessary in certain environments, but are not necessary for the normal functioning of bacteria
A
Plasmids
7
Q
- Conducted in vivo (in life)
- Should use when you want proteins or recombinant DNA
- Positives: obtain proteins, large quantities
- Negatives: must start with high-quality DNA, difficult with mammals
A
Cloning
8
Q
- Conducted in vitro (in a test tube)
- Should be used when you want specific sequence of DNA
- Positives: Amplifies small fragments of DNA, more selective
A
PCR
9
Q
Using fluorescent dyes to see where genes are expressed
A
in situ Hybridization
10
Q
Genome-wide expression studied using DNA ???
A
microarrays
11
Q
- Useful because it examines a large number of genes from a small tissue sample
- Examines mRNA
- Detects presence (yes/no) and intensity
- Screens 1000s of genes at a time
- Developed using knowledge of the genome
- *Look for start codons to identify genes
- *Determines function of the gene
A
Microarrays
12
Q
A plate that contains DNA
A
Array
13
Q
Pros: new technology
Cons: Expensive, requires prior knowledge of the genome, results may be hard to interpret (don’t know the functions of all the genes)
A
Microarrays
14
Q
Unspecialized cells that can both reproduce itself indefinitely or differentiate into specialized cells
A
Stem Cells
15
Q
Stem cells from embryos
- Can divide indefinitely
- Pluripotent-can differentiate into a wide variety of cells
A
Embryonic Stem Cells
16
Q
Stem cells from adults
-Can only give rise to a few different varieties of cells
A
Adult Stem Cells
17
Q
- In 2007, obtained from skin cells
- Researchers introduced 4 ‘stem cell’ master regulatory genes
- Not exactly the same as embryonic stem cells
- May be useful to use to treat patients >they won’t reject their own cells
- May be useful to obtain cell cultures to study disease
A
Induced Pluripotent Stem Cells (iPS)
18
Q
- Introducing genes into an afflicted individual for therapeutic purposes
- Works best if genetic disease is caused by a single, mutant gene
- Is a ‘forever fix’ only if treated cells multiply throughout the patient’s life
- Examples: LCA2, SCID (severe combined immunodeficiency), liver therapy
A
Gene Therapy
19
Q
Many technical issues
-How can the activity of the transferred gene be controlled?
-How can we be sure that the insertions of the therapeutic gene doesn’t harm some other necessary cell function?
Many ethical issues
-‘Tampering’ with human genes
-Should we be manipulating genes in human germ lines (egg&sperm)?
A
Gene Therapy
20
Q
- DNA testing can identify guilty or innocent individuals from blood, semen, or tissue left at crime scenes
- *Cannot tell identical twins apart
- Identify the victim of a crime
- *After the attack in 2001, 10,000 samples of victims were tested and 3,000 were identified
A
Forensic Evidence
21
Q
Genetically modified organisms
- Most are crops: corn, soybeans, canola
- Widespread in US, Argentina, Brazil
- 80% of the world’s average devoted to crops
- Not accepted in Europe
- *Fear that crops will pass their genes to close relatives… ‘super weeds’ may arise
- *Protein products may lead to allergic reactions
A
GMOs
22
Q
The application of computational methods to the storage and analysis of biological data
A
Bioinformatics
23
Q
The study of whole sets of genes and their interactions
A
Genomics
24
Q
The study of whole sets of proteins
A
Proteomics
25
- Smaller 1-6 Mb
- Fewer genes
- Higher gene density
Prokaryotic Genomes
26
- Larger 12-3000 Mb
- More genes
- Lower gene density
Eukaryotic Genomes
27
With eukaryotes, there is a lot of ?? in genome size and variation
variation
28
Makes RNA (mRNA, rRNA, tRNA, miRNA)
Coding Regions
29
Does not make RNA
- Used to be called 'junk DNA'
- 500 regions are identical in humans, rats, and mice; suggests it has an important function
- Function is still largely unknown
Noncoding Regions
30
Characteristics of plant viruses?
RNA genome, Helical capsid
31
Symptoms of viral infections in plants?
Bleaching, brown spots, stunted growth
32
Research about the basic functioning and expression of genes and proteins
Basic Research
33
Research that solves a problem
Applied Research
34
The direct manipulation of genes for practical purposes
Genetic Engineering
35
Evolutionary developmental biology, compares developmental processes of different multicellular organisms
Evo-Devo
36
- Consists of genetic information and a protein coat
- Latin for 'poison' (causes a variety of diseases)
- Cannot reproduce without a host cell
- Much smaller than both bacteria and a cell
Virus
37
Used to classify viruses
- DNA or RNA
- Single-stranded or double-stranded
- Linear or circular
- 4-1000 genes
Genetic Material
38
Protein shell
- Comes in many shapes
- May also have viral envelopes (derived from host membrane, has host's proteins)
Capsids
39
Culminates in the death (lysis) of the host cell and release of new viruses
New phage DNA & proteins are synthesizes & assembled into phages>the cell lyses, releasing phages>the phage injects its DNA> phage DNA circularizes
Lytic Cycle
40
Viral DNA is replicated without killing host cell
Phage DNA integrates into the bacterial chromosome, becoming a prophage>the bacterium reproduces, copying the prophage & transmitting it to daughter cells>cell division produces a population of bacteria infected with the prophage>daughter cells with prophage>phage DNA circularizes
Lysogenic Cycle
41
Why haven't viruses been eliminated?
The viruses mutate at a high level; receptors that are used in viruses, humans also use for survival
42
A harmless variant of a pathogen that stimulates the immune system to mount defenses against the pathogen
-Available to combat: smallpox, mumps, HPV, hepatitis B
Vaccines
43
Cannot be used to treat viruses, only treats bacteria infections
Antibiotics
44
Interferes with viral nucleic acid synthesis or the assembly of viruses
Antiviral Drugs
45
A virus that suddenly becomes apparent
Emergent Virus
46
A general outbreak of a disease (localized to 1 area)
Epidemic
47
A global outbreak (more than 1 continent)
Pandemic
48
Transmitted via air/sneezing
H1N1 Influenza
49
Transmitted via physical contact
Zika & Ebola
50
RNA viruses have a high rate of mutation, influenza
Mutation of existing viruses
51
Dissemination increases if virus can be transferred human to human, Zika
Dissemination from a small, isolated human population
52
Ebola
Spread of existing viruses from animals to humans
53
What is a characteristic of the lytic cycle?
A large number of phages is released at a time
54
What property of life is shared by eukaryotes and prokaryotes, but not viruses?
The ability to process energy through metabolic reactions
55
Why was influenza pandemic, but zika and ebola epidemic?
Influenza can be spread in the air, so it can be spread over a greater area
56
Plant is infected by an external source, generally via open wounds caused by wind, injury, or herbivores (insects)
Horizontal Transmission
57
Viral infection passed from parent plant to offspring (via both asexual and sexual reproduction)
Vertical Transmission
58
Transplanting nucleus from one cell to another
Nuclear Transplantation
59
Heat briefly to separate DNA strands
Denaturing
60
Cool to allow primers to form hydrogen bonds with end of target sequence
Annealing
61
DNA polymerase adds nucleotides to the 3' end of each primer
Extension
