00
Correct
00
Incorrect
00 : 00 : 0 00
Session Time
00 : 00
Average Question Time ( Secs)
Retry this test Dashboard

  • Question 1 - Regarding Southern Blotting and DNA probes, which answer is FALSE ...

    Incorrect

    • Regarding Southern Blotting and DNA probes, which answer is FALSE

      Your Answer: Gene probes can consist of DNA or RNA

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

      Explanation:

      Restriction enzymes always cut at different positions. There are different restriction endonucleases for different nucleotide sequences.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      36.4
      Seconds

  • Question 2 - Which of the following conditions is NOT X-linked recessive? ...

    Correct

    • Which of the following conditions is NOT X-linked recessive?

      Your Answer: Cystic fibrosis

      Explanation:

      Cystic fibrosis is a autosomal recessive disease with an incidence of about 1 in 2500 live births. The most common mutation occurs in the long arm of chromosome 7 which codes for the chloride channel (cystic fibrosis transmembrane conductance regulator) gene.

      To have CF, a child must inherit two abnormal genes—one from each parent. The recessive CF gene can occur in both boys and girls because it is located on non-sex-linked chromosomes called autosomal chromosomes.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      9.9
      Seconds

  • Question 3 - In most somatic cells telomeres progressively shorten as: ...

    Incorrect

    • In most somatic cells telomeres progressively shorten as:

      Your Answer: The host ages

      Correct 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
      6.8
      Seconds

  • Question 4 - Three adjacent nucleotides code for a particular amino acid. These are called codons....

    Correct

    • Three adjacent nucleotides code for a particular amino acid. These are called codons. How many common amino acids are there and how many potential codon combinations make up the genetic code?

      Your Answer: 20 amino acids, 64 codon combinations

      Explanation:

      There are around 20 amino acids and 61 out of the 64 combinations of codon code for these 20 common amino acids.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      26.7
      Seconds

  • Question 5 - 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
      19.7
      Seconds

  • Question 6 - During which stage does the mitotic apparatus dissolute? ...

    Incorrect

    • During which stage does the mitotic apparatus dissolute?

      Your Answer: Prophase

      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
      34.3
      Seconds

  • Question 7 - When during the cell cycle does DNA replication occur? ...

    Incorrect

    • When during the cell cycle does DNA replication occur?

      Your Answer: Mitosis

      Correct 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
      20.6
      Seconds

  • Question 8 - Defects in chromosomal structure (and examples) include those mentioned below except: ...

    Incorrect

    • Defects in chromosomal structure (and examples) include those mentioned below except:

      Your Answer:

      Correct Answer: Lyonization (x-linked disorders)

      Explanation:

      All are true except for A) Lyonization which is the inactivation of the X chromosomes in a female. It is not a chromosomal abnormality.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      0
      Seconds

  • Question 9 - Which of the following is true for P 53: ...

    Incorrect

    • Which of the following is true for P 53:

      Your Answer:

      Correct Answer: It is induced by ‘broken’ DNA

      Explanation:

      All of the above mentioned statements are true regarding tumour suppressor genes.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      0
      Seconds

  • Question 10 - Which of the following is true for P53: ...

    Incorrect

    • Which of the following is true for P53:

      Your Answer:

      Correct Answer: It is induced by ‘broken’ DNA

      Explanation:

      P53 gene is activated as a result of damaged DNA and if that cannot be repaired then it activates apoptosis.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      0
      Seconds

  • Question 11 - 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:

      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
      0
      Seconds

  • Question 12 - Regarding restriction fragment length polymorphisms (RFLP) and Gene Knockout Mouse Models. All are...

    Incorrect

    • Regarding restriction fragment length polymorphisms (RFLP) and Gene Knockout Mouse Models. All are true except:

      Your Answer:

      Correct Answer: In knockout mouse models a gene is turned on through targeted mutation

      Explanation:

      In RFLP, polymorphism occurs in 98% of the non coding genome, resulting in no phenotypical change in the organism. A gene is not turned on by a mutation, rather the mutation at the restriction site will alter the DNA and the DNA will now form fragments of different lengths. PCR is a better technique than RFLP.

      A knockout, as related to genomics, refers to the use of genetic engineering to inactivate or remove one or more specific genes from an organism. Scientists create knockout organisms to study the impact of removing a gene from an organism, which often allows them to then learn something about that gene’s function.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      0
      Seconds

  • Question 13 - During which phase of the cell cycle does transcription of DNA synthesis molecules...

    Incorrect

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

      Your Answer:

      Correct 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.

      Interphase is composed of G1 phase (cell growth), followed by S phase (DNA synthesis), followed by G2 phase (cell growth). At the end of interphase comes the mitotic phase, which is made up of mitosis and cytokinesis and leads to the formation of two daughter cells.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      0
      Seconds

  • Question 14 - Which of the following are true with regard to autosomal recessive disorders: ...

    Incorrect

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

      Your Answer:

      Correct Answer: All are true

      Explanation:

      All are true for autosomal recessive disorders.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      0
      Seconds

  • Question 15 - 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:

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

      Explanation:

      Mitochondrial DNA (mtDNA) does indeed lack introns, meaning that its genes are closely packed with coding sequences. This actually means that any point mutation in the mtDNA is more likely to have an effect, not less. The lack of introns means there are fewer non-coding regions where mutations can occur without affecting gene function. Thus, mutations in mtDNA often have significant consequences because they are more likely to alter essential coding sequences.

      The other statements are true:

      • Most mitochondrial diseases are myopathies and neuropathies with a maternal pattern of inheritance: This is correct because mtDNA is inherited maternally, and many mitochondrial disorders affect muscle and nerve function.
      • Retinal degeneration, diabetes mellitus, and some forms of hearing loss are some of the other diseases attributed to mitochondrial chromosome defects: These are indeed conditions associated with mitochondrial defects.
      • Mitochondrial chromosome defects are inherited from one’s mother: This is correct, as mtDNA is passed from mother to offspring.
      • Leber’s hereditary optic neuropathy (LHON), the commonest cause of blindness in young men, is an example of a mitochondrial chromosome defect: This is true; LHON is a well-known mitochondrial disorder.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      0
      Seconds

  • Question 16 - The length of DNA is generally measured in terms of the number of:...

    Incorrect

    • The length of DNA is generally measured in terms of the 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 17 - The enzyme responsible for telomeres maintaining their length after cell division is called:...

    Incorrect

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

      Your Answer:

      Correct 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
      0
      Seconds

  • Question 18 - Which of the following conditions results from chromosomal ‘non-disjunction’? ...

    Incorrect

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

      Your Answer:

      Correct 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
      0
      Seconds

  • Question 19 - Which statement is correct? ...

    Incorrect

    • Which statement is correct?

      Your Answer:

      Correct 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
      0
      Seconds

  • Question 20 - Regarding Gene Knockout Mouse Models, all are true except: ...

    Incorrect

    • Regarding Gene Knockout Mouse Models, all are true except:

      Your Answer:

      Correct Answer: In knockout mouse models a gene is turned on through targeted mutation

      Explanation:

      In knockout mouse models, a gene is not turned on but rather turned off or “knocked out” through targeted mutation. This involves disrupting or deleting the gene to study the effects of its loss of function. Knockout models are crucial for understanding the roles of specific genes, particularly those with unknown functions.

      The other statements are true:

      • Knockout models are important in studying the roles of sequenced genes with unknown function.
      • RFLP (Restriction Fragment Length Polymorphisms) can be subcategorized as SLP (single locus probe) and MLP (multi locus probe).
      • RFLP analysis is slow and cumbersome and is now largely obsolete, having been replaced by more efficient techniques.
      • Sequence changes involved in RFLP can be analyzed more quickly by PCR (Polymerase Chain Reaction).

    • This question is part of the following fields:

      • Genetics
      • Medicine
      0
      Seconds

  • Question 21 - Consanguinity shows a strong association with which pattern of inheritance? ...

    Incorrect

    • Consanguinity shows a strong association with which pattern of inheritance?

      Your Answer:

      Correct Answer: Autosomal recessive

      Explanation:

      Consanguinity involves being from the same kinship as another person. It is a common feature of an autosomal recessive mode of inheritance

    • This question is part of the following fields:

      • Genetics
      • Medicine
      0
      Seconds

  • Question 22 - Which of the following is false with regard to the following statement: Proto-...

    Incorrect

    • Which of the following is false with regard to the following statement: Proto- oncogenes can be transformed to oncogenes in the following ways.

      Your Answer:

      Correct Answer: Inhibition of P53

      Explanation:

      Proto oncogenes cannot be transformed into oncogenes due to inhibition of P53 gene. There has to be a mutation in the proto oncogene. All the other options are true.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      0
      Seconds

  • Question 23 - The process where by DNA fragments are separated by size and charge is...

    Incorrect

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

      Your Answer:

      Correct 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
      0
      Seconds

  • Question 24 - What is the protective hexametric sequence at the ends of chromosomes called? ...

    Incorrect

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

      Your Answer:

      Correct 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
      0
      Seconds

  • Question 25 - With regards to P53, which statement is NOT true? ...

    Incorrect

    • With regards to P53, which statement is NOT true?

      Your Answer:

      Correct Answer: P53 is a RNA binding protein

      Explanation:

      P53 is a tumour suppressor gene. It is not an RNA binding protein. It has been implicated in almost all tumours. It regulates the progression from G1 to the S phase of the cell cycle and is activated in response to damaged DNA.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      0
      Seconds

  • Question 26 - 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 27 - 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:

      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
      0
      Seconds

  • Question 28 - 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 29 - During which phase are the 2 chromatids pulled apart at the centromere? ...

    Incorrect

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

      Your Answer:

      Correct 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
      0
      Seconds

  • Question 30 - 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

SESSION STATS - PERFORMANCE PER SPECIALTY

Genetics (2/7) 29%
Medicine (2/7) 29%
Passmed
Retry this test Dashboard