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  • Question 1 - During which phase of meiosis does exchange of genetic material occur accounting for...

    Correct

    • During which phase of meiosis does exchange of genetic material occur accounting for genetic diversity between individuals:

      Your Answer: Prophase 1

      Explanation:

      Prophase 1 has been divided into five different stages ( laptotene, zygotene, pachytene, diplotene ans diakinesis). In prophase 1 chromosomes are going to condense to become visible, each chromosome will contain two chromatids that are joined at the centromere. the nucleolus and nuclear envelope are going to disintegrate. the homologous chromosomes will form tetrad and crossing over will occur between the chromosomes (random exchange of genes), the point of exchange is known as the chiasmata, this increases genetic diversity.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      7.4
      Seconds

  • Question 2 - 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
      6.8
      Seconds

  • Question 3 - Which of the following is an incorrect statement regarding the structure of DNA?...

    Correct

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

      Your 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
      4
      Seconds

  • Question 4 - When during the cell cycle does DNA replication occur? ...

    Correct

    • When during the cell cycle does DNA replication occur?

      Your Answer: S phase

      Explanation:

      The S phase is known as the synthesis phase. During this phase DNA will begin to replicated, as well as the synthesis of the centrosomes and associated proteins.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      6.4
      Seconds

  • Question 5 - Immortality can result from over expression of which enzyme? ...

    Correct

    • Immortality can result from over expression of which enzyme?

      Your Answer: Telomerase

      Explanation:

      Telomerase activity is seen in germ cells and is absent in somatic cells. Telomeres prevent the chromosomes from shortening and prevent the coding portion of the DNA from being lost, thus allowing the cell to replicate indefinitely.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      3.9
      Seconds

  • Question 6 - 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
      2.4
      Seconds

  • Question 7 - 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
      6.7
      Seconds

  • Question 8 - 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
      3.6
      Seconds

  • Question 9 - In meiosis, the period of prophase 1 involves: ...

    Incorrect

    • In meiosis, the period of prophase 1 involves:

      Your Answer: DNA replication

      Correct 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
      11.4
      Seconds

  • Question 10 - 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
      3.7
      Seconds

  • Question 11 - In most somatic cells telomeres progressively shorten as: ...

    Correct

    • In most somatic cells telomeres progressively shorten as:

      Your Answer: The cell divides

      Explanation:

      Telomerase activity is seen in germ cells and is absent in somatic cells. A somatic cell is any biological cell forming the body of an organism, other than a gamete, germ cell, gametocyte or undifferentiated stem cell. i.e. liver cells. Telomeres prevent the chromosomes from shortening and prevent the coding portion of the DNA from being lost, thus allowing the cell to replicate indefinitely. During replication telomeres may be lost resulting in cell death.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      7.7
      Seconds

  • Question 12 - The process of DNA amplification and quantification is called: ...

    Incorrect

    • The process of DNA amplification and quantification is called:

      Your Answer:

      Correct Answer: PCR

      Explanation:

      PCR/polymerase chain reaction is a procedure carried out in a test tube that can be used on the smallest amount of DNA to amplify it, allowing for millions of copies of specific nucleotides to be made.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      0
      Seconds

  • Question 13 - Telomeres are best described as: ...

    Incorrect

    • Telomeres are best described as:

      Your Answer:

      Correct 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
      0
      Seconds

  • Question 14 - The length of DNA is generally measured in terms of number of: ...

    Incorrect

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

      Your Answer:

      Correct 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
      0
      Seconds

  • Question 15 - 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:

      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
      0
      Seconds

  • Question 16 - Which of the following are true when it comes to tumour suppressor genes:...

    Incorrect

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

      Your Answer:

      Correct 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
      0
      Seconds

  • Question 17 - 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:

      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
      0
      Seconds

  • Question 18 - Which statement is incorrect? ...

    Incorrect

    • Which statement is incorrect?

      Your Answer:

      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
      0
      Seconds

  • Question 19 - 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:

      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
      0
      Seconds

  • Question 20 - Which of the following statements is true regarding chromosomes? ...

    Incorrect

    • Which of the following statements is true regarding chromosomes?

      Your Answer:

      Correct 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
      0
      Seconds

SESSION STATS - PERFORMANCE PER SPECIALTY

Genetics (10/11) 91%
Medicine (10/11) 91%
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