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  • Question 1 - In RFLP (restriction fragment length polymorphism), the DNA fragments are separated by length...

    Correct

    • In RFLP (restriction fragment length polymorphism), the DNA fragments are separated by length through a process known as:

      Your Answer: Agarose gel electrophoresis

      Explanation:

      Samples of DNA from individuals are broken into pieces by restriction enzymes and the fragments are separated according to their lengths via gel electrophoresis. Although now largely obsolete due to the rise of inexpensive DNA sequencing technologies, RFLP analysis was the first DNA profiling technique inexpensive enough to see widespread application.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      36.2
      Seconds

  • Question 2 - Regarding DNA cloning and sequencing, all of the following are true, except: ...

    Incorrect

    • Regarding DNA cloning and sequencing, all of the following are true, except:

      Your Answer: Monitoring of fluorescence give gene sequence

      Correct Answer: Yeast artificial chromosomes ( yacs) are vectors

      Explanation:

      Yeast chromosomes cannot be used as a vector. All the rest are true. Vectors can be bacteria, viruses and plasmids. DNA ligase binds the DNA fragment to the host DNA after insertion. Fluorescence can be used to visualize them.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      56
      Seconds

  • Question 3 - Which statement about X linked dominant disorders is FALSE? ...

    Correct

    • Which statement about X linked dominant disorders is FALSE?

      Your Answer: Heterozygous females tend to have the disease more severely than affected males.

      Explanation:

      Women who have the affected X chromosome will be affected, but the severity will be less than that in males as they have a normal X chromosome to counter the effect of the mutated X chromosome. Affected males will pass on the defect to their daughters 100% of the time but not to their sons.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      50.1
      Seconds

  • Question 4 - The enzyme responsible for Telomeres to maintain their length after cell division is...

    Incorrect

    • The enzyme responsible for Telomeres to maintain their length after cell division is called:

      Your Answer: Telomere transcriptase

      Correct Answer: Telomerase reverse transcriptase

      Explanation:

      Telomeres are non-coding DNA consisting of repetitive nucleotide sequences plus proteins that are found at the end of the linear chromosomes. They maintain the integrity of the chromosomes and prevent their shortening.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      28.2
      Seconds

  • Question 5 - Under normal conditions (where n represents the number of chromosome pairs), just before...

    Incorrect

    • Under normal conditions (where n represents the number of chromosome pairs), just before mitosis begins, how many chromosomes are contained in the nucleus of each somatic cell:

      Your Answer: 2n

      Correct Answer: 4n

      Explanation:

      In a normal somatic cell there are 2n chromosome but in a replicating cell just before mitosis the chromosomes duplicate but are still joined via the centrosome. Thus there are 4n chromosomes. After completion of mitosis the number goes back to 2n.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      29.9
      Seconds

  • Question 6 - Normal parents have a child with a recessive condition, Tay Sachs. The chance...

    Incorrect

    • Normal parents have a child with a recessive condition, Tay Sachs. The chance of them having a normal child is?

      Your Answer: 25%

      Correct Answer: 75%

      Explanation:

      The chance for normal parents having a child with a recessive disease is 1:4 or 25%. As both the parents are heterozygous for this condition. They have a 3:4 chance of having a normal child or 75%.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      18.4
      Seconds

  • Question 7 - The process where by DNA fragments are separated by size and charge is...

    Correct

    • The process where by DNA fragments are separated by size and charge is called:

      Your Answer: Gel electrophoresis

      Explanation:

      Fragments of DNA of varying length can be separated on the basis of their charge and their size by a process called gel electrophoresis. Because DNA contains negatively charged phosphate groups, it will migrate in an electric field toward the positive electrode. Shorter chains migrate more rapidly through the pores of the gel, and thus separation depends on length. DNA bands in the gel can be visualized by various techniques including staining with dyes and autoradiography.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      19.3
      Seconds

  • Question 8 - Which of the following are true when it comes to tumour suppressor genes:...

    Correct

    • Which of the following are true when it comes to tumour suppressor genes:

      Your Answer: All of the options are true

      Explanation:

      All of the above mentioned statements are true regarding tumour suppressor genes. Tumour suppressor genes generally follow the two-hit hypothesis, which implies that both alleles that code for a particular protein must be affected before an effect is manifested.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      31.9
      Seconds

  • Question 9 - Which of the following is not true regarding mitochondrial chromosome disorders? ...

    Incorrect

    • Which of the following is not true regarding mitochondrial chromosome disorders?

      Your Answer: Retinal degeneration, diabetes mellitus and some forms of hearing loss are some of the other disease attributed to mitochondrial chromosome defects

      Correct Answer: Because mitochondrial chromosomes have no introns in their genes, any point mutation has a low likelihood of having an effect.

      Explanation:

      Any point mutation in any part of the mitochondrial DNA will lead to a mutated mitochondria and will likewise have its ill effect on the body.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      101.3
      Seconds

  • Question 10 - The telomerase is capable of adding several more repeats of telomeres at which...

    Incorrect

    • The telomerase is capable of adding several more repeats of telomeres at which end of the guanosine rich region.

      Your Answer: 5th end

      Correct Answer: 3rd end

      Explanation:

      Telomerase is a reverse transcriptase that uses the RNA template to synthesize DNA in the 5th-3rd direction resulting in extension of the 3rd end and then translocates it to the newly synthesized end. The GT rich strand is thus elongated.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      35.7
      Seconds

  • Question 11 - Which of the following statements is true about chromosomes? ...

    Correct

    • Which of the following statements is true about chromosomes?

      Your Answer: All of the above

      Explanation:

      All of the above mentioned statements are true regarding chromosomes.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      60.6
      Seconds

  • Question 12 - In which phase do chromosomes in the nucleus become completely condensed into well-defined...

    Incorrect

    • In which phase do chromosomes in the nucleus become completely condensed into well-defined chromosomes?

      Your Answer: Telophase

      Correct Answer: Metaphase

      Explanation:

      Prophase begins when the nucleus envelope disintegrates and the chromosomes start to condense. The chromosomes consist of two sister chromatids that are joined at a constriction known as centromere. When the cell reaches the metaphase the chromosomes are completely condensed and ready to align on the equatorial plate

    • This question is part of the following fields:

      • Genetics
      • Medicine
      55.4
      Seconds

  • Question 13 - Telomerase is active in the following cells except: ...

    Correct

    • Telomerase is active in the following cells except:

      Your Answer: Certain osteoblasts

      Explanation:

      Some cells have the ability to reverse telomere shortening by expressing telomerase, an enzyme that extends the telomeres of chromosomes. Telomerase is an RNA-dependent DNA polymerase, meaning an enzyme that can make DNA using RNA as a template.

      Telomerase is not usually active in most somatic cells (cells of the body), but it’s active in germ cells (the cells that make sperm and eggs) and some adult stem cells. These are cell types that need to undergo many divisions, or, in the case of germ cells, give rise to a new organism with its telomeric “clock” reset.
      Interestingly, many cancer cells have shortened telomeres, and telomerase is active in these cells. If telomerase could be inhibited by drugs as part of cancer therapy, their excess division (and thus, the growth of the cancerous tumor) could potentially be stopped.
       A subset of liver cells with high levels of telomerase renews the organ during normal cell turnover and after injury.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      68.9
      Seconds

  • Question 14 - Which of the following with regard to DNA mutations does not fit: ...

    Incorrect

    • Which of the following with regard to DNA mutations does not fit:

      Your Answer: All of them fit

      Correct Answer: All gene mutations cause clinical disease entities

      Explanation:

      All gene mutations do not cause a clinical manifestation of the disease, some gene mutations are silent mutations. They are present but do not cause any disease.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      47.2
      Seconds

  • Question 15 - Carcinogens found in cigarette smoke can transform proto-oncogenes to oncogenes through: ...

    Incorrect

    • Carcinogens found in cigarette smoke can transform proto-oncogenes to oncogenes through:

      Your Answer: Inhibiting tumour suppressor genes.

      Correct Answer: Point mutations in genomic DNA

      Explanation:

      80% of the pancreatic cancers are environmentally influenced by smoking which increases the risk by 50%. Mutation can occur in the KRAS, p16, SMAD4, and TP53 genes among other tumour suppression genes. Smoking can be implicated in transformation of all these genes. Apart from KRAS all the genes are inactivated in pancreatic cancer. As KRAS is the most commonly altered gene, mutation occurs as point mutation. As smoking is the most common aetiology in pancreatic cancer, and KRAS is the most important gene that is altered. Most commonly cigarette smoke causes point mutation.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      20.3
      Seconds

  • Question 16 - Which statement is incorrect regarding transcription of DNA? ...

    Incorrect

    • Which statement is incorrect regarding transcription of DNA?

      Your Answer: Primary mRNA consists of both introns and exons.

      Correct Answer: A gene is always read in the 3’-5’ orientation and at 3’ promoter sites.

      Explanation:

      In both prokaryotes and eukaryotes RNA polymerase acts in the 5′-3′ direction and hence the RNA is transcribed in this direction. The mRNA produced is immature as it has introns as well as exons presents. It undergoes a process known as splicing to remove the exons and then interacts with the ribosomes to form proteins.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      61
      Seconds

  • Question 17 - Which of the following with regard to autosomal dominant disorders are true: ...

    Incorrect

    • Which of the following with regard to autosomal dominant disorders are true:

      Your Answer: The offspring of a heterozygous individual has a 25% chance of inheriting the chromosome carrying the disease allele

      Correct Answer: The offspring of a heterozygous individual has a 50% chance of inheriting the chromosome carrying the disease allele

      Explanation:

      50% of the children will be effected from parents who are heterozygous for an autosomal dominant disorder. An allele can be dominant or recessive. Individuals, meanwhile, can be homozygous or heterozygous: individuals who are homozygous for a certain gene carry two copies of the same allele. individuals who are heterozygous for a certain gene carry two different alleles.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      79.5
      Seconds

  • Question 18 - What is the role of cyclin and cyklin-dependent kinases in mitosis: ...

    Correct

    • What is the role of cyclin and cyklin-dependent kinases in mitosis:

      Your Answer: Phosphorylation of proteins that make up pre-replication complexes

      Explanation:

      There are certain regulators of the cell cycles that mediate progression through the cell cycle. These are cyclins and cyklin-dependent kinases (CDKs). They form a complex that phosphorylates protein involved in the cell cycle.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      30.6
      Seconds

  • Question 19 - Southern Blotting and DNA probes: ...

    Correct

    • Southern Blotting and DNA probes:

      Your Answer: DNA fragments are separated by gel electrophoresis and transferred onto membrane sheets in southern blotting

      Explanation:

      A Southern blot is a method used in molecular biology for detection of a specific DNA sequence in DNA samples. Southern blotting combines transfer of electrophoresis-separated DNA fragments to a filter membrane and subsequent fragment detection by probe hybridization. The other forms of blotting involve the use of RNA and proteins.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      42.1
      Seconds

  • Question 20 - What is the structure of nucleosomes? ...

    Correct

    • What is the structure of nucleosomes?

      Your Answer: Strands of double strand DNA + histones

      Explanation:

      DNA is packed and condensed by binding to histone proteins. The double stranded DNA forms a complex with histone proteins which is called a nucleosome. There are 8 histone proteins contained in one core of nucleosome.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      15.3
      Seconds

  • Question 21 - Which of the following is an incorrect statement regarding the structure of DNA?...

    Incorrect

    • Which of the following is an incorrect statement regarding the structure of DNA?

      Your Answer: A nucleotide is a base joined to a sugar phosphate unit.

      Correct Answer: The two strands of DNA are held together by cysteine bonds.

      Explanation:

      The two strands of DNA are held together by hydrogen bonds formed between the nucleotide bases.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      42.3
      Seconds

  • Question 22 - Which of the following conditions results from chromosomal ‘non-disjunction’? ...

    Correct

    • Which of the following conditions results from chromosomal ‘non-disjunction’?

      Your Answer: All of the options

      Explanation:

      Non-disjunction can result in aneuploidy i.e. abnormal number of chromosomes in a cell. It results due to uneven division of chromosomes in the meiosis 1 or 2 phase. All the above mentioned examples are of non-disjunction.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      21.4
      Seconds

  • Question 23 - In meiosis, the period of prophase 1 involves: ...

    Correct

    • In meiosis, the period of prophase 1 involves:

      Your Answer: Replicated DNA condensing to form visible chromosomes

      Explanation:

      Prophase 1 has been divided into five different stages (laptotene, zygotene, pachytene, diplotene and diakinesis). In prophase 1, chromosomes are going to condense to become visible, each chromosome will contain two chromatids that are joined at the centromere.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      32.3
      Seconds

  • Question 24 - In which phase do chromosomes in the nucleus become condensed into well-defined chromosomes?...

    Correct

    • In which phase do chromosomes in the nucleus become condensed into well-defined chromosomes?

      Your Answer: Metaphase

      Explanation:

      Prophase begins when the nucleus envelope disintegrates and the chromosomes start to condense. The chromosomes consist of two sister chromatids that are joined at a constriction known as centromere. When the cell reaches the metaphase the chromosomes are completely condensed and ready to align on the equatorial plate

    • This question is part of the following fields:

      • Genetics
      • Medicine
      12.8
      Seconds

  • Question 25 - At the end of which phase will P53 halt the cell cycle? ...

    Incorrect

    • At the end of which phase will P53 halt the cell cycle?

      Your Answer: S phase

      Correct Answer: G1 phase

      Explanation:

      P53 regulates the cell cycle. It regulates the progression from G1 to S phase

    • This question is part of the following fields:

      • Genetics
      • Medicine
      18.5
      Seconds

  • Question 26 - During which phase are the 2 chromatids pulled apart at the centromere? ...

    Correct

    • During which phase are the 2 chromatids pulled apart at the centromere?

      Your Answer: Anaphase

      Explanation:

      During the prometaphase the microtubule organizing centre completely develops. The spindle fibers attach to the chromosome and the centriole. It is in the Anaphase however that the spindle fibers contract pulling the sister chromatids apart. Later in the anaphase a cleave furrow beings to forms.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      7.2
      Seconds

  • Question 27 - Regarding Polymerase Chain Reaction, all are true except: ...

    Incorrect

    • Regarding Polymerase Chain Reaction, all are true except:

      Your Answer: Is an in vitro technique

      Correct Answer: There is a linear rise of DNA copies during amplification.

      Explanation:

      All are true except there is a linear rise of DNA copies during amplification. There is an exponential rise in amplification of DNA.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      37.3
      Seconds

  • Question 28 - When 2 nucleotide chains of DNA bind together, thymine is bound to: ...

    Correct

    • When 2 nucleotide chains of DNA bind together, thymine is bound to:

      Your Answer: Adenine

      Explanation:

      As a general rule in the structure of DNA, thymine always binds to adenine with two hydrogen bonds, cytosine always binds to guanine with three hydrogen bonds and vice versa. However In the structure of RNA the only difference is that adenine binds to uracil instead of thymine. But thymine will always bind to adenine.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      20.6
      Seconds

  • Question 29 - Which of the following are true with regard to autosomal recessive disorders: ...

    Correct

    • Which of the following are true with regard to autosomal recessive disorders:

      Your Answer: All are true

      Explanation:

      All are true for autosomal recessive disorders.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      47.8
      Seconds

  • Question 30 - The chromosomes that principally encode for proteins or RNA molecules involved in mitochondrial...

    Incorrect

    • The chromosomes that principally encode for proteins or RNA molecules involved in mitochondrial function are found:

      Your Answer: In the mitochondria of the cell

      Correct Answer: In the nucleus of each diploid cell

      Explanation:

      While mitochondria have their own small circular DNA (mtDNA) that encodes some of the proteins and RNAs required for mitochondrial function, the majority of proteins involved in mitochondrial function are encoded by nuclear DNA. These nuclear genes are transcribed in the nucleus and then translated into proteins in the cytoplasm. The proteins are subsequently imported into the mitochondria.

      Therefore, the correct answer is:

      • In the nucleus of each diploid cell

    • This question is part of the following fields:

      • Genetics
      • Medicine
      17.5
      Seconds

SESSION STATS - PERFORMANCE PER SPECIALTY

Genetics (15/30) 50%
Medicine (15/30) 50%
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