In PTE Academic exam, summarize spoken text and retell lecture questions are often from the real lectures or speech interception. One of the most repeated topics in PTE ‘Summarize Spoken Text’ is DNA & RNA. The lecture provided here is ‘DNA Barcoding’. To help the students, the team at English2language have collected “Summarize Spoken Text” lectures close to PTE real exam topics. You will be provided with PTE practice audio and question transcript here.

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PTE Academic Listening – Summarize Spoken Text


PTE Summarize Spoken Text Exercise – DNA BARCODING




DNA barcoding was invented by Paul Hebert of the University of Guelph, in Ontario, Canada, in 2003. His idea was to generate a unique identification tag for each species based on a short stretch of DNA. Separating species would then be a simple task of sequencing this tiny bit of DNA. Dr Hebert proposed part of a gene called cytochrome c oxidase I (COI) as suitable to the task. All animals have it. It seems to vary enough, but not too much, to act as a reliable marker. And it is easily extracted, because it is one of a handful of genes found outside the cell nucleus, in structures called mitochondria.

The idea worked, and it has dramatically reduced the time (to less than an hour) and expense (to less than $2) of using DNA to identify species. And thus, in July this year, Dr Victor’s mystery goby became Coryphopterus kuna. It was the first vertebrate to have its DNA barcode—a sequence of about 600 genetic “letters”—included in its official description.

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  1. The topic for this lecture is DNA bar coding. It was discovered in 2000, by the scientists of a university in Ontario, Canada. The purpose of this experiment was to assign a unique identification tag for each species. All animals have DNA and vary. This experiment was successful and helped to reduce the time and money to identify the species based on DNA.

  2. Topic of the lecture was DNA barcoding . It was discovered in 2003. DNA is basically a unique identification tag for each species. It works based on sequencing. DNA helps to identify species and have reduced time , effort of doctors and money as less as 2$.

  3. The speaker was discussing “Invention of DNA Barcode in sequencing species”.
    He mentioned Dr Paul Herbert’s contribution in sequencing species based on DNA in the field.
    He described how DNA: COI, outside of nucleus is reliable, unique and sufficient tag for classification.
    He discussed how the idea dramatically reduced the cost and time.
    He concluded how the discovery led to sequencing of first vertebrate.

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