Archive for the ‘PCR Polymerase Chain Reaction Forum – Troubleshooting Questions & Answers’ Category
Last Updated on Friday, 10 June 2011 04:32 Written by Administrator Friday, 10 June 2011 04:32
Question by Samm(:: bio,, PLEASE PLEASE PLEASE.?
1. Advances in biotechnology have made it possible for scientists to synthesize human insulin.
A) True
B) False
2. Currently, there are no known risks in genetically modifying crop species.
A) True
B) False
3. One technique used to separate DNA fragments of different lengths is:A) gel electrophoresis
B) gene pharming
C) polymerase chain reaction
D) selective breeding
4. Restriction enzymes:A) weld together fragments of DNA
B) attach to DNA molecules at specific sites and cut both strands of DNA at that place
C) only cut RNA molecules at specific sites and cut both strands of DNA at that place
D) are chemical machines that make parts of the cell membrane
5. DNA ligase:A) links together the “sticky ends” of cut DNA segments
B) attaches to DNA molecules at specific sites and cut both strands of DNA at that place
C) only cuts RNA molecules at specific sites and cuts both strands of DNA at that place
D) is a chemical machine that makes parts of the cell membrane
6. Self-replicating DNA fragments found in bacterial cells are called:A) alleles
B) anthers
C) bacteriophages
D) plasmids
7. Vectors are:A) enzymes that cut DNA at specific sequences
B) DNA molecules used to carry foreign DNA fragments into bacteria or other cells
C) RNA molecules that can be joined with DNA fragments that are to be cloned
D) large eukaryotic chromosomes
8. Polymerase chain reaction (PCR):A) is a relatively simple and is a fast way of copying very small amounts of DNA
B) was developed during the 1980s
C) resulted in its discoverer sharing a Nobel Prize
D) all of these
9. The current estimate of the number of genes in the human genome is:A) 1000
B) 24,000
C) 100,000
D) 50,000
Best answer:
Answer by ????
1. True
2. False
3. idk sorry
4. C
5. D
6. D
7. B
8. D
9. B
Add your own answer in the comments!
Tags: Please | Posted under PCR Polymerase Chain Reaction Forum - Troubleshooting Questions & Answers | 1 Comment
Last Updated on Thursday, 9 June 2011 08:30 Written by Administrator Thursday, 9 June 2011 08:30
Question by Mickey Mouse: Can you help me with my Biology homework please and thank-you Multiple choice?
1. Selective breeding produces huskies strong enough to pull sleds.
T True
F False
2. Genetic engineering inserts a bioluminescent gene into a tobacco plant.
T True
F False
3. Gel electrophoresis produces a plant that is disease-resistant like one parent and more nutritious like the second parent.
T True
F False
4. Recombinant DNA technology combines a DNA fragment with DNA from a different source.
T True
F False
5. Hybridization produces large numbers of identical DNA molecules.
T True
F False
6. Gel electrophoresis separates DNA fragments by size.
T True
F False
7. A test cross can help a gardener determine that a rose plant has a
A genotype rr.
B genotype Rr.
C phenotype rr.
D phenotype Rr.
8. Which do scientists use to cut genomic DNA into smaller fragments to isolate specific genes?
A DNA ligase
B recombinant DNA
C restriction enzymes
D transgenic bacteria
9. How many genes make up human DNA?
A 5000 to 10,000
B 20,000 to 25,000
C 45,000 to 50,000
D 70,000 to 75,000
10. Which is an example of selective breeding?
A breeding tomatoes to increase fruit size
B crossing two plants with desirable traits
C inserting genes from one plant into another
D returning bred plants to their natural habitat
11. Which is a disadvantage of hybridization?
A Hybridization is harmful to the affected organisms.
B Hybridization is technically difficult to perform.
C Hybridization is inferior to genetic engineering.
D Hybridization is time-consuming and expensive.
12. Which is the process by which unwanted aggressive behaviors are bred out of certain types of dogs?
A hybridization
B inbreeding
C selective breeding
D test crosses
13. Which process is applied to identify mutations or errors in DNA molecules?
A DNA sequencing
B gel electrophoresis
C polymerase chain reaction
D recombinant DNA technology
14. Which process separates DNA fragments by size?
A DNA sequencing
B gel electrophoresis
C polymerase chain reaction
D recombinant DNA technology
15. The primary goal of the HapMap project is to
A catalog the genetic sequences of individual DNA.
B create a database for genetic, biological information.
C identify genes that cause serious human diseases.
D map the sequence of nucleotides in human DNA.
Best answer:
Add your own answer in the comments!
Last Updated on Tuesday, 7 June 2011 08:32 Written by Administrator Tuesday, 7 June 2011 08:32
Question by laura: How does a thermal cycler help the process of PCR?
Best answer:
Answer by Roberto
It uses a Peltier block to heat and chill the tubes very rapidly. It does it over and over again through the PCR, that’s why it’s called thermal cycler (thermal = heats and chills, cycler = over and over).
Give your answer to this question below!
Tags: CYCLER., help, process, thermal | Posted under PCR Polymerase Chain Reaction Forum - Troubleshooting Questions & Answers | Comments Off
Last Updated on Monday, 6 June 2011 04:32 Written by Administrator Monday, 6 June 2011 04:32
Question by Jenny Hirsh: How does single cell real-time PCR work?
How does single cell real-time PCR work? What are the important differences between single cell RT-PCR and normal RT-PCR?
Best answer:
Answer by Hibiscus
Real-time PCR measures PCR amplification as it occurs and this technique is sensitive enough to enable quantitation of RNA from a single cell.. RT-PCR completely revolutionizes the way one approaches PCR-based quantitation of DNA and RNA. In traditional PCR, results are collected after the reaction is complete, making it impossible to determine the starting concentration of nucleic acid.
RT-PCR is the most sensitive technique for mRNA detection and quantitation currently available.
There are several key differences between real-time PCR and non real-time PCR:
Advantages of Real-Time PCR
- Increased dynamic range of detection
- No post-PCR processing
- Detection is capable down to a 2-fold change
- Collects data in the exponential growth phase of PCR
- An increase in reporter fluorescent signal is directly proportional to the number of amplicons generated
- The cleaved probe provides a permanent record amplification of an amplicon
Disadvantages of Non Real-Time (Traditional) PCR
- Poor Precision
- Low sensitivity
- Short dynamic range < 2 logs
- Low resolution
- Non-Automated
- Size-based discrimination only
- Results are not expressed as numbers
- Ethidium bromide for staining is not very quantitative
- Post-PCR processing
Know better? Leave your own answer in the comments!
Tags: Cell, RealTime, single, work | Posted under PCR Polymerase Chain Reaction Forum - Troubleshooting Questions & Answers | Comments Off