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Correct OPTION is (b) An effector cell

The best I can explain: It is possible to design bispecific antibodies. Bispecific antibodies can either BIND to 2 antigen or bind with antigen and with another effector cell/conjugate cell. By binding with effector cell, it increases the efficacy of the REACTIONS to happen and THUS more chances of getting positive results.

Right choice is (d) Cytokine

To EXPLAIN: MONOCLONAL antibodies are modified to deliver any toxin, radioisotope, cytokine or other active conjugates used for treatment purposes. Bispecific antibodies that can BIND with their Fab regions both to the TARGET antigen and to a conjugate or effector cell are also produced. Antibodies similar to human antibodies are produced so that they don’t suffer immune rejections.

Right answer is (a) True

The explanation is: mAbs act directly when binding to CANCER-specific antigens and induce an immunological response to cancer cells. Such as inducing cancer cell apoptosis, inhibiting growth, or interfering with a key FUNCTION. This is one of the reasons for the application of MONOCLONAL antibodies in the cancer treatment FIELD.

Correct choice is (d) Purification of drugs

Easy EXPLANATION: Application of monoclonal antibody in the biosensors is a DIAGNOSTIC application of maps. Using in transplant rejection and infectious disease is the THERAPEUTIC application of monoclonal ANTIBODIES. Purification of drugs and imaging the TARGET is the clinical application of monoclonal antibody.

Right option is (a) True

The explanation: Monoclonal antibodies are employed in the manufacturing of BIOSENSORS and microarrays. Monoclonal antibodies since they are made from only one single antigen can be used to DETECT the PRESENCE of that antigen in the given sample. It can detect antigens in a very SMALL AMOUNT.

Correct option is (a) True

The explanation: Yes, bioterrorism can be fought with the help of Monoclonal antibodies. These are because bioterrorism most of the time MEANS by certain virus, bacteria will be engaged to take down a whole place. That microbe will be having a single antibody being produced in the host CELL. THUS, we can harvest these and MAY have a monoclonal antibody in the FUTURE.

Correct answer is (a) Antigen

The best explanation: For the hybridoma TECHNOLOGY the mouse is being injected with antigen. Antigen can be intact cell, whole cell membrane, microorganism, peptide, protein, heat killed cells. These are injected to activate the immune REACTION till the MAKING of MEMORY cells. Which can later be harvested for the PRODUCTION of monoclonal antibody.

The correct ANSWER is (c) Myeloma cells

The best EXPLANATION: The fusion of the cells is DONE between spleen cells and myeloma cells. The fusion should be done on a PEG medium. The cell plating should be done in HAT medium so that only hybridoma cells are alive after the required time. The scanning of the viable cells can be done by flow cytometry.

The correct option is (d) Discovery of the process of producing monoclonal antibodies

To explain I would say: The B-cell cancer myeloma was known, RESEARCHERS understood that these CANCEROUS B-cells all produce a single type of antibody. This theory was USED to study the STRUCTURE of antibodies. Later the process of producing monoclonal antibodies invented by GEORGES Köhler and César Milstein shared the Nobel Prize in Physiology or Medicine in 1984 for the discovery.

The correct choice is (d) Tissue culture method

To explain: Harvesting of MYELOMA CELLS can be done in both in vitro and in vivo METHODS. In in vitro, the cells can be propagated in bioreactors with sufficient nutrient, pH control, oxygen, sterile environment. And these can ALSO be propagated in vivo by INJECTING them into a mouse and just feeding and taking proper care of the mouse.

Right OPTION is (a) 8 – Azaguanine

Best explanation: The myeloma cells harvested from the antigen injected mouse has to be added with 8-Azaguanine. 8-Azaguanine tends to stop the de NOVO PATHWAY of and the cells which cannot survive will DIE. Myeloma cells which are HGPRT- will be the only cells growing in the culture due to the presence of the compound. These cells will have high viability and rapid growth.

Right option is (c) MCA

To elaborate: MCA or monoclonal antibodies are a very important tool in the field of BIOCHEMISTRY, molecular biology, and medicine. Through this process, it is possible to CREATE monoclonal antibodies which will be specifically BINDING to that substance. This tool is very safe, the mouse used don’t have to be killed, the safety and accuracy are high.

Right choice is (d) 2 WEEKS

Easiest explanation: The FLOW CYTOMETRY has to be titer for 2 weeks. This is because the flow cytometry is a piece of very sensitive equipment. Once it has taken the INPUT the output cannot be changed. It separates cells on the basis of size, the GRANULARITY of the cell, charge (if present).

Right choice is (d) CANCER MYELOMA B-cell

Best EXPLANATION: In 1970 a new discovery said that B-cell cancer myeloma produces a single type of antibody. This discovery was used to STUDY the structure of antibodies. But it was not possible to produce identical antibodies which will be specific to given GENERA.

Correct ANSWER is (a) Beads

Explanation: Bead transfection produces breaks in the CELLULAR membrane USING beads. The adherent cells, glass beads and SOLUTION containing the DNA are all incubated together. Then the solution is mixed such that the beads collide with each other so that any cells coming in between two beads will get a mechanical shock producing small pores.

The correct choice is (a) True

To explain I WOULD say: Chemotherapeutic surrounds the cells. When an electric current is passed the increased membrane, permeability allows access to the CYTOSOL. This makes the pores to open. And the chemical can go inside the cells. The electric FIELD is applied after injecting the chemotherapeutic inside the affected AREA.

Right option is (a) True

The explanation: The efficiency of this rapid technique depends on the CONCENTRATION of DNA in a solution, the timing of the addition of DNA, SIZE and CONDITION of the beads and the buffers UTILIZED. In this method, the adherent cells are incubated for a brief period with glass beads in a solution containing the DNA. Then the m=solution is MIXED such that the beads collide and the cells coming in between the beads may get pores.

Correct CHOICE is (b) Bactofection

The BEST I can explain: Bacterial GENE delivery is known as Bactofection and viral gene delivery is known as transduction. Bactofection is a METHOD of direct gene transfer using BACTERIA into the target cell, tissue, organ or organism. Various bacterial strains used as vectors are L. monocytogenes, S. Typhimurium.

Correct option is (a) Poxvirus

Easy explanation: Poxvirus/ vaccinia virus does not get INCORPORATED into the genome of the host CELL. They reside in the cytoplasm and REPLICATE in the cytoplasm. Thus, they help in TRANSIENT transformation RATHER than permanent transformation. The genome size of pox/ vaccinia virus is 300 kb.

Correct answer is (b) Physically breaking the cells

The best explanation: Bead transfection COMBINES the principle of physically producing breaks in the cellular membrane using BEADS. In this method, the adherent cells are incubated for a brief period with glass beads in a solution containing the DNA. Suspending cells in electroporation cuvette is for electroporation. BIOLISTIC is ALSO KNOWN as particle bombardment. Ultrasound is used in sonoporation.

Right option is (a) Fin focus of laser light is used

Best explanation: Laser-induced TRANSFECTION is the use of a brief pulse of a FOCUSED laser beam. Here, DNA is mixed with the cells present in the culture. Then a FINE focus of laser beam is passed on the cell surface which will form a SMALL pore that will be SUFFICIENT for DNA uptake into the cells.

Right option is (d) Usage of ultrasound

To elaborate: Sonoporation USED ultrasound treatment for forming PORES on the cell membrane. A microbubble which has the DNA will be provided with s=ultra sound along with the cells in which DNA has to be INCORPORATED. The sound cause pores to be formed on the cell membrane and the bubble burst due to cavitation releasing the DNA into the SOLUTION.

The correct choice is (c) Also known as biolistics

For explanation: It was discovered by PROF Sanford at Cornell UNIVERSITY (USA). It is also known as Biolistics (biological ballistics) since a gun is used in the process. It employs high-velocity microprojectiles to deliver substances LIKE small drugs, DNA, etc into CELLS and TISSUES.

Right option is (b) Injecting the DNA into the CELL

To explain: Microinjection is the process where a micropipette is used to INJECT the foreign DNA straight into the nucleus of the cell. The cell will be held by a HOLDING pipette. Then the researcher can easily inject the DNA into the cell. This method is WIDELY used for various purposes.

The correct option is (d) 10000 – 100000 V/cm

To explain: Electroporation works by passing thousands of volts ACROSS a distance of one to two millimeters of suspended CELLS in an electroporation CUVETTE. 10000 – 100000 V/cm in a pulse LASTING a few microseconds or milliseconds is essential. More than that the cells will die. This moderate voltage and time ratio should be maintained such that the pores of the cells are only opened.

Correct choice is (a) Electroporation

The best explanation: In electroporation ELECTRIC field is applied ACROSS the cells suspended in an electroporation cuvette. The high voltage for a few milliseconds is ESSENTIAL. Since this will create transient pores on the cell membrane which will get REFILLED again.

The correct answer is (d) Baculoviral VECTOR system

Explanation: Gene transfer to ANIMAL cells has various biological and mechanical WAYS. The physical or mechanical ways are electroporation, microinjection, particle bombardment, SONOPORATION, laser-induced, bead transfection. The biological method is using various viral vectors for the transfer of DNA.

Correct answer is (a) Say in culturing

To explain I would say: Mammalian cells most commonly used for gene delivery. More importantly Human cells- allows the production of recombinant protein with authentic post-translational modifications. PRODUCTS which are made by gene TRANSFER are ANTIBODIES, hormones, growth FACTORS, cytokines, and vaccines.

Right answer is (a) STAYS F^–

For explanation: Since ENTIRE plasmid cannot TRANSFER the recipient remains F^–. Hfr cell can transfer a portion of the bacterial genome. The bacterium RECEIVING the genes do not become F^+.

The correct option is (d) B and C

Explanation: F-plasmids contain genetic information that is not present in the BACTERIAL CHROMOSOMES, although they can be integrated with the chromosomes.

Right answer is (b) F^–CELL becomes F^+

For explanation: CONJUGATION occurs between positive and negative F cells. The donor cell will have pilus and this pilus will attach to the recipient cell THUS BRINGING the two cell together. The F plasmid will be an EPISOME.

The correct choice is (B) Lac, Gal, Azi, Ton

The BEST explanation: The HFR can be produced by incorporation of the plasmid within the DNA at different POSITIONS. So here in two CASES, the position is different. Considering the relative time of entry, we can see a pattern which agrees with option 2. It can be in either ORIENTATION.

The correct answer is (b) False

Easy EXPLANATION: In F^+ and F^– mating the F factor is replicated by rolling cycle replication and taken up by the RECIPIENT cell. THUS the recipient cell becomes F^+ not F^–. Due to the replication and transfer of F factor both the BACTERIA BECOME F^+.

Correct answer is (a) E. colli

The explanation is: SELF TRANSMISSIBLE PLASMID are only present on gram positive bacteria such as Bacillus, Streptococcus, Enterococcus, Staphylococcus, and Streptomyces. For these organisms the sex pilus is not required for plasmid TRANSFER.

Correct choice is (d) HFR and F+

The explanation is: For conjugation to TAKE PLACE ONE bacterium must have the F plasmid and OTHERS should lack it. HFR has the components of F plasmid within its genome so it can’t mate with ANOTHER F+.

The correct answer is (a) True

To EXPLAIN: SELF transmissible plasmids are present in gram positive bacteria. Few transfer genes are required for gene transfer in this system. It doesn’t incorporate a sex PILUS for plasmid transfer.

Right option is (a) DONOR cell

The best EXPLANATION: Few transfer GENES are required for gene transfer in this system. It doesn’t incorporate a sex pilus for plasmid transfer. Donor and recipient CELLS adhere to each other using specialised plasmid encoded PROTEIN released by the donor cell.

Right choice is (a) Filter

The explanation: After 4 hours of incubation in the medium WITHIN U tube Davis found that since the bacteria were not allowed for DIRECT contact they could not exchange GENETIC MATERIAL. It was the fritted glass filter that allowed the passage of the media but not the bacteria.

Correct option is (b) Bernard Davis

To explain: Lederberg and TATUM did not PROVE the FACTS of conjugation. The evidence for conjugation was provided by Berners Davis. He proved the fact that physical contact of cells was necessary for gene transfer. It was in the YEAR 1950.

Right answer is (a) The F plasmid encodes the FACTOR which is transferred from one CELL to another

To explain: F plasmid encodes the factor called Fertility or F factor. It is transferred from one cell to another by the sex pilus. It is present in E. coli and for the conjugation to TAKE place; bacteria can also BELONG to DIFFERENT species.

Right option is (d) JOSHUA Lederberg and Edward Tatum

For explanation I would say: The evidence for CONJUGATION was discovered by the experiment of Joshua Lederberg and Edward Tatum in the year 1946. They found out genetic material can be transferred by DIRECT cell to cell CONTACT.

The correct choice is (c) Deoxy ribonucleases

To elaborate: After DNA entry into a CELL, one STRAND is immediately degraded by deoxy ribonucleases, while the other strand undergoes base pairing with a HOMOLOGOUS portion of the RECIPIENT cell CHROMOSOME.

The correct CHOICE is (c) Late logarithmic phase

For explanation I would say: Conditions SUITABLE for UPTAKE of donor DNA into recipient CELLS occur only during the late logarithmic phase of growth. In the logarithmic phase, the bacteria KEEP on dividing.