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Topic last updated: 24 Nov 2021
    • Biologybiology Biology
    • Ico Human Biology Human biology
    • 16+
    • 55

Unravelling the genome

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Quiz: unravelling the genome - answers

Test your knowledge of the Human Genome Project and the associated science with this on-line quiz. Select the correct answer from the multi-choices. When you have answered all 8 questions you may check your answers by clicking the button below.

1. How long did the Human Genome Project take to complete the first ever sequencing of the human genome?

  •  13 years

It was expected to take 15 years but advances in sequencing technology speeded the process up considerably.

2. Approximately how many genes in the human genome code for specific proteins?

  •  19,000

– perhaps fewer than you might imagine – and fewer than the scientists first estimated at the end of the Human Genome Project!

3. The Human Genome Project is an example of international scientific cooperation. How many countries were involved in sequencing the DNA?

  •  18

They include the US, the UK, Australia, France…

4. During the sequencing process an enzyme is used to build up DNA fragments. The enzyme used is

  • DNA polymerase

DNA polymerase which builds up DNA molecules during normal replication.
DNA ligase joins the sticky ends in genetic engineering.
Restriction endonucleases cut segments out of the genome in genetic engineering.
Salivary amylase is a digestive enzyme produced in the mouth.

5. During the sequencing process different length fragments of DNA are produced. They are labelled with different coloured fluorescent tags depending on the final base attached. The terminating bases which halt the DNA synthesis are known as:

  •  dideoxynucleotide bases

When they are added at random the terminate the synthesis sequence.
Nucleotide bases are normal nitrogenous bases which go to make up the DNA strand, adenine is an example of a nucleotide and uracil is a base found only in RNA.

6. The fluorescently labelled DNA fragments are separated by a process known as:

  •  gel electrophoresis

The DNA fragments are placed on a gel and move in an electric field. The shortest fragments move furthest.
Chromatography is a simpler separation of substances using a solid phase and a solvent travelling over it.
Spectrometry is the analysis of chemicals in special machines known as spectrometers.
Centrifugation involves the separation of different fractions as a result of spinning a mixture at high speed.

7. The findings of the Human Genome Project are expected to have many positive benefits to medicine and health. Which of these developments is NOT linked to the sequencing of the human genome?

  •  the development of new synthetic materials for use in artificial joints

All of the other developments are closely linked to the unravelling of the human genome

8. Approximately what percentage of the human genome codes directly for proteins?

  •  less than 2%

The rest of the genome, known as non-coding DNA, has a variety of functions, which include regulating which proteins are made, when they are made, and how they are packaged. There is still a great deal to discover about the role of the non-coding DNA!