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

  • Question 1 - 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
      75.5
      Seconds

  • Question 2 - The chromosomes that principally encode for proteins or RNA molecules involved in mitochondrial...

    Correct

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

      Your Answer: In the mitochondria of the cell

      Explanation:

      DNA is found in chromosomes and in the mitochondria of a cell. The only way for the protein or RNA to be formed is by transcription via the DNA and translation into proteins.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      47
      Seconds

  • Question 3 - The enzyme responsible for Telomeres to maintain their length after cell division is...

    Correct

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

      Your 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
      62.1
      Seconds

  • Question 4 - 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
      13.5
      Seconds

  • Question 5 - 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
      82.7
      Seconds

  • Question 6 - In a knockout mouse model the process used to combine the new DNA...

    Incorrect

    • In a knockout mouse model the process used to combine the new DNA sequence and the stem cells is known as:

      Your Answer: Chimerisation

      Correct Answer: Insertion

      Explanation:

      Chimerisation is also known as the formation of recombinant DNA. When a foreign DNA sequence is inserted into a plasmid or other DNA sequence, this process is known as insertion.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      23.8
      Seconds

  • Question 7 - 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: Prophase

      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
      28
      Seconds

  • Question 8 - The process of DNA amplification and quantification is called: ...

    Correct

    • The process of DNA amplification and quantification is called:

      Your 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
      13.8
      Seconds

  • Question 9 - 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
      19.1
      Seconds

  • Question 10 - In DNA cloning and sequencing, the bases in nucleotides chains are bound together...

    Incorrect

    • In DNA cloning and sequencing, the bases in nucleotides chains are bound together by:

      Your Answer: Double-helical structure

      Correct Answer: Hydrogen bonding.

      Explanation:

      Nucleotides will always bind together via hydrogen bonds. There are two hydrogen bonds present between thymine and adenine and three hydrogen bonds present between guanine and cytosine.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      58.4
      Seconds

  • Question 11 - 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
      133.3
      Seconds

  • Question 12 - 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
      17.1
      Seconds

  • Question 13 - 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
      12.6
      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
      25.5
      Seconds

  • Question 15 - The mitochondrial chromosome is a circular DNA molecule. They encode for proteins needed...

    Incorrect

    • The mitochondrial chromosome is a circular DNA molecule. They encode for proteins needed for ATP production. These proteins are also essential for:

      Your Answer: Cell replication

      Correct Answer: Apoptotic cell death

      Explanation:

      The intrinsic pathway or the mitochondrial pathway of apoptosis is activated due to the loss of BCL-2 and other antiapoptotic proteins. This loss results in the increased membrane permeability and release of cytochrome C which activates caspases downstream resulting in apoptosis.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      49.4
      Seconds

  • Question 16 - 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
      33.3
      Seconds

  • Question 17 - Which of the following conditions results from chromosomal ‘non-disjunction’? ...

    Incorrect

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

      Your Answer: Down syndrome

      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
      8.6
      Seconds

  • Question 18 - 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
      21.8
      Seconds

  • Question 19 - Which of the following with regard to DNA mutations does not fit: ...

    Correct

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

      Your 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
      47.8
      Seconds

  • Question 20 - “Ploidy” is a term used to refer to the number of chromosomes in...

    Correct

    • “Ploidy” is a term used to refer to the number of chromosomes in cells. Cancer cells are commonly:

      Your Answer: Aneuploidy

      Explanation:

      Cancer cells most commonly undergo disordered cell growth and cell division. This results in an additional number of chromosomes called aneuploidy. This is a characteristic of cancer cells along with variation in differentiation of the cells.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      12.2
      Seconds

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

    Correct

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

      Your 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
      6.7
      Seconds

  • Question 22 - 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
      61.2
      Seconds

  • Question 23 - 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
      11.3
      Seconds

  • Question 24 - 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
      45
      Seconds

  • Question 25 - 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
      14.5
      Seconds

  • Question 26 - 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
      17.8
      Seconds

  • Question 27 - 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
      45.9
      Seconds

  • Question 28 - Which statement is incorrect? ...

    Correct

    • Which statement is incorrect?

      Your 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
      67.2
      Seconds

  • Question 29 - Regarding restriction fragment length polymorphisms (RFLP) and Gene Knockout Mouse Models. All are...

    Correct

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

      Your 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
      131.4
      Seconds

  • Question 30 - The following cells replicate without shortening their telomeres because they express telomerase. ...

    Incorrect

    • The following cells replicate without shortening their telomeres because they express telomerase.

      Your Answer: Stem cells

      Correct Answer: Germ cells

      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. During replication telomeres may be lost resulting in cell death.

    • This question is part of the following fields:

      • Genetics
      • Medicine
      61.7
      Seconds

SESSION STATS - PERFORMANCE PER SPECIALTY

Genetics (22/30) 73%
Medicine (22/30) 73%
Passmed
Retry this test Dashboard