1.
What type of post-translational modification is not a blanket term?
Correct Answer
A. Hydroxylation
Explanation
Hydroxylation is not a blanket term because it specifically refers to the addition of a hydroxyl group (-OH) to a molecule. It is a specific type of post-translational modification that can occur on proteins, lipids, and other biomolecules. In contrast, alkylation, prenylation, and acylation are more general terms that encompass a variety of different modifications involving the addition of alkyl, prenyl, or acyl groups, respectively. Therefore, hydroxylation is the correct answer as it is not a blanket term for post-translational modifications.
2.
What type of polymerase should be used in PCR?
Correct Answer
D. Taq
Explanation
Taq polymerase should be used in PCR because it is a DNA polymerase that is derived from the thermophilic bacteria Thermus aquaticus. It is heat resistant and can withstand the high temperatures required for PCR amplification. Taq polymerase also has a high processivity, meaning it can efficiently replicate DNA over long stretches without falling off the template strand. Additionally, Taq polymerase has a 5' to 3' polymerase activity and lacks a 3' to 5' exonuclease proofreading activity, making it suitable for PCR applications where high fidelity is not essential.
3.
Who helped create Sanger Sequencing?
Correct Answer
C. Alan Coulson
Explanation
Alan Coulson is credited with helping to create Sanger Sequencing. Sanger Sequencing, also known as chain-termination sequencing, is a method used to determine the sequence of nucleotides in DNA. It was developed by Frederick Sanger and his colleagues in the late 1970s. Alan Coulson, along with other scientists, contributed to the development and refinement of this technique, which revolutionized DNA sequencing and paved the way for many important discoveries in genetics and molecular biology.
4.
What Polymerase is used for Microarrays?
Correct Answer
B. Reverse Transcriptase
Explanation
Reverse transcriptase is the polymerase used for microarrays. Reverse transcriptase is an enzyme that can synthesize complementary DNA (cDNA) from an RNA template. In microarray experiments, RNA samples are often converted into cDNA using reverse transcriptase before they are applied to the microarray chip. This allows the detection and analysis of gene expression levels. Reverse transcriptase is commonly used in microarray technology due to its ability to convert RNA into cDNA, which can then be amplified and labeled for further analysis.
5.
What are ddNTPs?
Correct Answer
C. DNTPS without a 3'-OH group
6.
What does RFLP stand for?
Correct Answer
A. Restriction Length Fragment PolymorpHism
Explanation
RFLP stands for Restriction Length Fragment Polymorphism. This technique is used in molecular biology to analyze genetic variations. It involves cutting DNA molecules into fragments using restriction enzymes and then separating and identifying these fragments. The variations in the length of these fragments can indicate differences in the DNA sequence between individuals or species.
7.
How are transformed cells usually uncovered after cloning vectors have been used?
Correct Answer
B. Treated with antibiotics
Explanation
After cloning vectors have been used, transformed cells can be uncovered by treating them with antibiotics. This is because cloning vectors often contain antibiotic resistance genes, which are inserted into the cells during the cloning process. Only cells that have successfully taken up the cloning vector and thus acquired the antibiotic resistance gene will be able to survive and grow in the presence of antibiotics. Therefore, treating the cells with antibiotics allows for the identification and selection of transformed cells.
8.
What type of blot uncovers DNA?
Correct Answer
A. Southern
Explanation
A Southern blot is a laboratory technique used to uncover and detect specific DNA sequences. It involves the separation of DNA fragments by gel electrophoresis, followed by transferring the DNA onto a membrane. The membrane is then exposed to a labeled DNA probe that binds specifically to the target DNA sequence, allowing for its detection. This technique is particularly useful for analyzing DNA samples and identifying specific genes or mutations.
9.
What is one factor that affects DNA Probe Binding? ________
Correct Answer
Salt Concentration, Temperature
Explanation
Salt concentration and temperature are factors that can affect DNA probe binding. Salt concentration refers to the amount of salt present in a solution, and it can affect the electrostatic interactions between the DNA probe and its target. Higher salt concentration can disrupt these interactions and decrease binding efficiency. Temperature also plays a role in DNA probe binding as it can affect the stability of the DNA duplex. Higher temperatures can cause the DNA strands to separate, reducing the binding efficiency of the probe. Therefore, both salt concentration and temperature are important factors to consider when optimizing DNA probe binding.
10.
Which is better for labelling, and why?
Correct Answer
A. FluoropHores, no artifacts or radiation
Explanation
Fluorophores are better for labelling because they do not produce any artifacts or radiation. This means that they do not interfere with the sample being labeled or cause any unwanted effects. Additionally, fluorophores provide a brighter color, which allows for easier detection and visualization of the labeled molecule. On the other hand, radioactive labels may also provide a brighter color, but they are more likely to dissociate from larger molecules, which can lead to inaccurate results.
11.
How does DNA Hybridization work?
Correct Answer
A. Denature, then anneal to different species strand to see how similar
Explanation
DNA hybridization works by denaturing the DNA strands, which involves separating the double-stranded DNA into single strands. Then, these denatured strands are annealed or combined with single strands from a different species. By observing how similar the DNA sequences are and how well they hybridize or bind together, scientists can determine the degree of similarity between the two species. This technique is commonly used in genetic research and diagnostics to compare DNA sequences and identify genetic variations or similarities between different organisms.
12.
In Electrophoresis, a larger molecule will move ________
Correct Answer
Slower
Explanation
In electrophoresis, a larger molecule will move slower. This is because the movement of molecules in electrophoresis is influenced by their size and charge. Larger molecules have more mass and therefore experience more resistance as they move through the gel or solution. This resistance slows down their movement, causing them to migrate at a slower rate compared to smaller molecules. Additionally, larger molecules tend to have a higher charge-to-mass ratio, which also contributes to their slower movement as they interact more strongly with the electric field.
13.
________ provides a set of rules for scaling and background correction in microarrays.
Correct Answer
LIMMA
Explanation
LIMMA is a widely used software package in bioinformatics that provides a set of rules for scaling and background correction in microarrays. It is specifically designed for analyzing gene expression data and offers methods to normalize and adjust the data to account for technical variations. LIMMA uses statistical models and algorithms to accurately estimate expression levels and identify differentially expressed genes. Its implementation of scaling and background correction ensures reliable and accurate analysis of microarray data.
14.
Aves and Crocodylia have the most recent common ancestor of Diapsida with which group? ________
Correct Answer
Lepidosauria
Explanation
Aves and Crocodylia have the most recent common ancestor of Diapsida with the group Lepidosauria. This means that Aves (birds) and Crocodylia (crocodiles) share a common ancestor with the group Lepidosauria, which includes reptiles such as lizards and snakes. The Diapsida is a group of reptiles that includes birds, crocodiles, and lizards, among others. Therefore, the correct answer is Lepidosauria, as it is the group that shares the most recent common ancestor with Aves and Crocodylia.
15.
In Electrophoresis, a more negative molecule will move ________
Correct Answer
quickly
Explanation
In electrophoresis, a more negative molecule will move quickly. This is because electrophoresis is a technique that separates molecules based on their charge and size. Since the molecule in question is more negative, it will be attracted towards the positive electrode and move faster towards it. The speed of movement is directly proportional to the magnitude of the charge, so a more negative molecule will move quickly in electrophoresis.
16.
Southern Blotting can occur on the material ________.
Correct Answer
Nylon, Nitrocellulose
Explanation
Southern Blotting is a technique used to detect specific DNA sequences in a sample. It involves transferring DNA from a gel onto a solid support, such as a nylon or nitrocellulose membrane. These materials have a high affinity for DNA and allow for the immobilization of DNA fragments, which can then be probed with labeled DNA or RNA molecules to identify the target sequence. Therefore, Southern Blotting can occur on nylon and nitrocellulose materials.
17.
A VNTR is anywhere from 10 to ________ base pairs long.
Correct Answer
100
Explanation
A VNTR (Variable Number Tandem Repeat) is a DNA sequence that is repeated multiple times in a genome. The length of a VNTR can vary, but it is typically anywhere from 10 to 100 base pairs long.
18.
What is a VNTR? ________
Correct Answer
Variable Number Tandem Repeat
Explanation
A VNTR, or Variable Number Tandem Repeat, refers to a DNA sequence that contains multiple repeating units of nucleotides. These repeating units can vary in length between individuals, which makes VNTRs useful for genetic profiling and forensic analysis. By comparing the number and length of VNTR repeats in different individuals, scientists can determine genetic variations and establish relationships between individuals. This technique is commonly used in DNA fingerprinting and paternity testing.
19.
Each STR will be shared between 5 to ________% of people.
Correct Answer
20
Explanation
Each STR will be shared between 5 to 20% of people.
20.
What is another factor that affects DNA Probe Binding? ________
Correct Answer
Salt Concentration, Temperature
Explanation
Salt concentration and temperature are both factors that can affect DNA probe binding. Higher salt concentrations can disrupt the electrostatic interactions between the negatively charged DNA and the positively charged probe, making it more difficult for the probe to bind to the DNA. Temperature can also impact the binding process, as higher temperatures can increase the kinetic energy of the molecules, allowing for more collisions and potentially increasing the binding efficiency. Therefore, both salt concentration and temperature play important roles in DNA probe binding.