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  • Question 1 - When during the cell cycle do the centrioles replicate? ...

    Incorrect

    • When during the cell cycle do the centrioles replicate?

      Your Answer: G2 phase

      Correct Answer: G1 phase

      Explanation:

      During G1 phase the cell will prepare for cell division. All the organelles will start to duplicate in this phase and the cell will begin to grow whilst proteins are also synthesized.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      19.3
      Seconds

  • Question 2 - During which stage does the mitotic apparatus dissolute? ...

    Incorrect

    • During which stage does the mitotic apparatus dissolute?

      Your Answer: Anaphase

      Correct Answer: Telophase

      Explanation:

      In telophase the nuclear envelope along with the nucleolus will reappear. The daughter nuclei will enlarge as the chromosome will decondense again. Along with this, cytokinesis will occur. At the end of cytokinesis the daughter centrioles will move from the poles to the intercellular bridge where they will be disassembled and complete the separation of the daughter cells

    • This question is part of the following fields:

      • Genetics
      • Medicine
      106.6
      Seconds

  • Question 3 - Regarding DNA cloning and sequencing, all of the following are true, except: ...

    Correct

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

      Your 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
      43.4
      Seconds

  • Question 4 - Near the transcription site of a gene, the site at which RNA polymerase...

    Correct

    • Near the transcription site of a gene, the site at which RNA polymerase and its cofactors bind is known as the:

      Your Answer: Promotor

      Explanation:

      Transcription will begin when the RNA polymerase II binds to the promotor. The promotor is a sequence of 25 nucleotides found upstream from the start site of transcription. This promotor sequence is known as the TATA box. Transcription factors also bond along with RNA polymerase to this site to form a complex. However some may bind to regulatory elements proximal to the promotor site.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      17.6
      Seconds

  • Question 5 - During which phase of the cell cycle does DNA synthesis occur? ...

    Correct

    • During which phase of the cell cycle does DNA synthesis occur?

      Your Answer: S

      Explanation:

      DNA synthesis occurs in the S phase of the cell cycle. In the G1 phase the cell prepares to divide. In G2 the cellular organelles divide and in the M phase mitosis occur. In the G0 phase the cell becomes quiescent and does not divide further

    • This question is part of the following fields:

      • Genetics
      • Medicine
      3.3
      Seconds

  • Question 6 - The process whereby DNA fragments are separated by size and charge is called:...

    Correct

    • The process whereby 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
      26.3
      Seconds

  • Question 7 - When one of the two copies of the autosomes has a mutation and...

    Correct

    • When one of the two copies of the autosomes has a mutation and the protein produced by the normal form of the gene cannot compensate. The affected individual has an:

      Your Answer: Autosomal dominant disorder

      Explanation:

      An autosomal dominant trait will be expressed no matter the consequence. If one chromosome has a mutation the other will not be able to compensate for the mutation hence the protein formed will be mutated and will not function properly.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      30.1
      Seconds

  • Question 8 - The telomerase is capable of adding several more repeats of telomeres at which...

    Correct

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

      Your 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
      16.9
      Seconds

  • Question 9 - With regard to X linked disorders which of the following are true ...

    Incorrect

    • With regard to X linked disorders which of the following are true

      Your Answer: None of the above

      Correct Answer: X linked recessive disorders usually present in males and only very rarely present in homozygous females

      Explanation:

      All are true for autosomal recessive disorders. Dominance rules for sex-linked gene loci are determined by their behaviour in the female: because the male has only one allele (except in the case of certain types of Y chromosome aneuploidy), that allele is always expressed regardless of whether it is dominant or recessive.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      73.3
      Seconds

  • Question 10 - Mutation in RB can lead to the formation of which cancer? ...

    Correct

    • Mutation in RB can lead to the formation of which cancer?

      Your Answer: Retinoblastoma

      Explanation:

      Patients with a history of autosomal dominant familial retinoblastoma have at least one mutated copy of the RB gene. This predisposes the patient to develop retinoblastoma in one or both the eyes. Patients with a family history should be screened properly so that it can be detected and treated as early as possible.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      5.3
      Seconds

  • Question 11 - Which statement is correct? ...

    Correct

    • Which statement is correct?

      Your Answer: MtDNA principally encodes for proteins that are involved in oxidative phosphorylation for the production of ATP in the cell.

      Explanation:

      Mitochondria have no nucleus instead they contain their own free floating circular genome (MtDNA), which encodes 13 different subunits of proteins involved in oxidative phosphorylation. The remainder of the mitochondrial proteins are nuclear encoded, synthesized in the cytoplasm, and transported into the mitochondria.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      44.6
      Seconds

  • Question 12 - Which of the following is not true regarding mitochondrial chromosome disorders? ...

    Correct

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

      Your 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
      28.8
      Seconds

  • Question 13 - Restriction Enzymes... ...

    Correct

    • Restriction Enzymes...

      Your Answer: Cut DNA sequences at specific sites

      Explanation:

      Restriction endonucleases are enzymes that recognise short sequences of double stranded DNA and cut them at specific nucleotide points or sequences. These sequences differ for different restriction endonucleases.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      17.1
      Seconds

  • Question 14 - 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
      54.1
      Seconds

  • Question 15 - Which of the following statements is true regarding chromosomes? ...

    Correct

    • Which of the following statements is true regarding chromosomes?

      Your Answer: All are true

      Explanation:

      All of the above mentioned statements are true regarding chromosomes.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      24.9
      Seconds

  • Question 16 - 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
      17.7
      Seconds

  • Question 17 - 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
      41.6
      Seconds

  • Question 18 - In which stage of mitosis are the chromosomes most obvious or prominent? ...

    Correct

    • In which stage of mitosis are the chromosomes most obvious or prominent?

      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
      6.1
      Seconds

  • Question 19 - Telomerase is active in all of the following cells, except: ...

    Correct

    • Telomerase is active in all of the following cells, except:

      Your Answer: Certain liver cells

      Explanation:

      Telomerase is an enzyme that adds repetitive nucleotide sequences to the ends of chromosomes (telomeres), preventing their shortening during cell division. Telomerase activity is crucial for cells that divide frequently and need to maintain their telomere length for continued proliferation. These include:

      • Stem cells: They have high telomerase activity to maintain their long-term proliferative capacity.
      • Germ cells: These cells also have active telomerase to ensure the stability of genetic material across generations.
      • Certain white blood cells: Some immune cells, particularly those that need to proliferate in response to infection, show telomerase activity.
      • Certain cancer cells: Many cancer cells reactivate telomerase, which contributes to their uncontrolled growth and immortality.

      However, most somatic cells, including certain liver cells, do not exhibit significant telomerase activity. While some liver cells might show low levels of telomerase activity during regeneration, it is not generally active in normal, differentiated liver cells.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      11.2
      Seconds

  • Question 20 - At the end of which phase will P53 halt the cell cycle? ...

    Correct

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

      Your 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
      4.8
      Seconds

  • Question 21 - The length of DNA is generally measured in terms of the number of:...

    Correct

    • The length of DNA is generally measured in terms of the number of:

      Your Answer: Base pairs

      Explanation:

      As DNA is made up of nucleotides, its length is measured by the number of base pairs in the DNA molecules.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      7.2
      Seconds

  • Question 22 - The process by which RNA fragments are separated by gel electrophoresis and transferred...

    Incorrect

    • The process by which RNA fragments are separated by gel electrophoresis and transferred onto a membrane sheet is called:

      Your Answer: Southern blotting

      Correct Answer: Northern blotting

      Explanation:

      Blots of the gel can be made from using nitrocellulose paper. Northern blots are produced when a fragment of radioactive DNA hybridize with RNA on a nitrocellulose blot of a gel and southern blots are produced when DNA hybrize with DNA on a nitrocellulose blot of the gel.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      12.9
      Seconds

  • Question 23 - In which phase do chromosomes in the nucleus become completely condensed into well-defined...

    Correct

    • In which phase do chromosomes in the nucleus become completely 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
      68.2
      Seconds

  • Question 24 - Carcinogens found in cigarette smoke can transform proto-oncogenes to oncogenes through: ...

    Correct

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

      Your 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
      11.6
      Seconds

  • Question 25 - What is the protective hexametric sequence at the ends of chromosomes called? ...

    Correct

    • What is the protective hexametric sequence at the ends of chromosomes called?

      Your Answer: Telomere

      Explanation:

      Telomeres are non coding DNA 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
      8.3
      Seconds

  • Question 26 - The enzyme responsible for telomeres maintaining their length after cell division is called:...

    Correct

    • The enzyme responsible for telomeres maintaining their length after cell division is called:

      Your Answer: Telomerase

      Explanation:

      Telomerase is the enzyme responsible for maintenance of the length of telomeres by addition of guanine-rich repetitive sequences. Telomerase activity is exhibited in gametes and stem and tumor cells.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      11.5
      Seconds

  • Question 27 - 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
      34.9
      Seconds

  • Question 28 - 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
      15.2
      Seconds

  • Question 29 - Telomeres are best described as: ...

    Correct

    • Telomeres are best described as:

      Your Answer: A repetitive DNA sequence at the end of a DNA molecule.

      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
      29.6
      Seconds

  • Question 30 - Which statement is incorrect? ...

    Incorrect

    • Which statement is incorrect?

      Your Answer: AAUAAA acts as a cleavage signal for endonucleases.

      Correct Answer: Translation begins when the triplet (UGA) encoding for methionine is encountered.

      Explanation:

      Translation being when the codon for methionine is encountered which is AUG not UGA. This process is known as initiation. All the other options are correct.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      53.3
      Seconds

SESSION STATS - PERFORMANCE PER SPECIALTY

Genetics (24/30) 80%
Medicine (24/30) 80%
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