Bio Unit 5
During the process of RNA transcription, which of the following steps is not included?
Duplication
A student was observing slides of cell division. In one of the slides, he noticed loosely coiled chromatin depicting DNA duplication. Which phase of the cell cycle could it be?
S phase
Two important steps involved in genetic engineering are cutting the desired gene from its genome, then cutting the vector genome and pasting the gene into it. How is this carried out?
Using the same restriction enzyme for cutting the desired gene and the vector and using ligase for pasting the gene into the vector, is the correct answer
What is the role of DNA helicase during DNA replication?
unwinds and "unzips" the DNA
The sequence of an mRNA transcript is UGGCACUCCAG. What will be the sequence of the template DNA strand from which it was synthesized?
ACCGTGAGGTC
DNA seen during interphase of mitosis is in a diffused state called _____.
Chromatin
Which event marks the beginning of DNA replication?
Formation of replication fork
A chickenpox virus invaded a cell. Inside, the viral genes were expressed and the viral genetic information was transcribed and translated into viral capsid proteins. What happens when a cell transcribes a viral gene?
Host cell translates the viral gene.
"Tryptophan self-controls its synthesis." Justify this statement.
If an excess amount of Tryptophan is present in a cell, Tryptophan acts as a co-repressor, preventing the further synthesis of necessary enzymes for its production and thus its synthesis
A farmer produces two types of corn plants. One has larger sized kernels but fewer yields and another has smaller sized kernels with high yield. He wants to produce a corn plant with larger sized kernels with high yield. Which of these methods would be applicable for this?
Insert the gene responsible for larger sized kernels into the genome of the corn with smaller sized kernels and a high yield.
Which of these sentences is true about viruses?
It can reproduce only within other cells, is the correct answer
Which of the following is a chain smoker likely to develop?
Lung cancer
Which of the following best describes the relationship of solar UV radiation to the environment?
Mutagen
The lac operon constitutes all of these but _____
Promoter
Which of these is a common feature for the lac and trp operon?
Regulatory proteins bind to repressor
The agricultural research facility during a research accidentally changed the DNA sequence of a wheat plant from GCCATGTT to GCGTACTT and this mutation resulted in a stronger plant variety. What kind of mutation did the plant undergo?
Substitution
Analyze the following statements. Which of them is correct with respect to the RNA transcript formed by means of transcription?
The RNA transcript is complimentary to the DNA from which it is transcribed. Instead of thymine, it has uracil, which complements the adenine of DNA.
A scientist carries out an experiment on a hamster. He exposes the hamster to x-rays at regular intervals. This results in a germ line mutation in the hamster. What is the possible outcome on the progeny of the hamster?
The defect is carried forward to the progeny of the hamster
When you are exposed to sunlight for a long time, your skin, which otherwise appears normal, gets heavily tanned. What could be the reason?
The genes for melanin pigmentation remain turned on and prepare more melanin than usual to protect the skin from photo-damage when it is exposed to sunlight for long time.
"Synthesis of one protein cannot take place without the presence of another protein." Is this statement true or false and why?
This statement is true because every step in protein synthesis requires enzymes, which are nothing but proteins.
During the investigation of a murder case, the police found a few bloodstains on the body of the victim, a few bloodstains on the wall nearby, and a few hair follicles by the victim. How could this evidence be used to identify the murderer?
by matching the DNA in the hair follicles and in both blood samples (from the wall and from the victim) to that of the victim and to the DNA database of convicted offenders
Which of the following techniques is used by researchers to carry out DNA replication in vitro?
polymerase chain reaction
Gene expression in prokaryotes is regulated at which stage?
transcriptional and co-translational
