A doomsday vault for seeds
359 words over 31 numbered lines, then 6 parts worth 13 marks (Modular Unit 2 (4WBI2) style, 12–13 marks). Read the article, answer each part, then open its mark scheme and set your mark.
Illustrative article written for Scholar Lab, not a Pearson text. The biology is real; the studies, people and figures are invented or rounded for practice.
A doomsday vault for seeds
On a frozen mountainside in Svalbard, far north of mainland Norway, a
tunnel leads more than 100 metres into the rock. At the end are three
large rooms holding more than a million packets of seeds. This is the
Svalbard Global Seed Vault, sometimes called the doomsday vault. It
was opened in 2008 as a back-up for the world’s crop seeds.
Most countries already keep seed banks of their own, but these can be
damaged by war, floods or power cuts. The Svalbard vault stores
duplicate samples sent from seed banks all over the world. Each sample
usually contains about 500 seeds of one variety of a crop such as
rice, wheat, maize or beans. In an illustrative year, the vault
received about 30 000 new samples. The countries that send seeds still
own them, and only they can take them out again.
Before they are sent, the seeds are dried until their water content is
only about 5 per cent. In the vault they are kept at −18 °C. Under
these conditions, seeds of many crops can stay alive for hundreds of
years. Even if the cooling machines failed, the surrounding rock would
keep the rooms below freezing for a long time.
The vault does not only store the varieties grown by farmers today. It
also contains seeds of old local varieties and of wild relatives of
crop plants. Some of these plants carry alleles that are rare in
modern crops, such as alleles that give resistance to drought, high
temperatures or particular diseases. As the climate changes, plant
breeders may need these alleles.
In 2015, the vault was used for the first time. A seed bank in Syria
had been damaged during the war, and scientists withdrew samples that
they had stored in Svalbard. They planted the seeds in Morocco and
Lebanon, grew new plants and collected fresh seeds to rebuild their
collection. Later, they sent new samples back to the vault. The
scientists said that the vault had worked exactly as it was designed
to. Other seed banks now plan to copy the idea for the seeds of wild
plants that are in danger of extinction.
Read the article. Use the information in the article and your own knowledge to answer the questions. The lines in brackets show where to look; select them to highlight the text.
Use the information in the article and your own knowledge to answer the questions. The lines in brackets show you where to look; select them to highlight the text.
State what is meant by the term allele.
(1)Explain why drying the seeds and storing them at −18 °C helps the seeds to stay alive for a long time.
(3)Calculate the number of seeds the vault received in this year. Give your answer in standard form.
(2)Explain why it is important to store seeds of wild relatives of crop plants.
(2)Describe how a plant breeder could use selective breeding to produce a variety of wheat that is resistant to drought.
(3)Give two conditions the seeds needed for germination when they were planted.
(2)Total for this question: 13 marks
0 / 13 marks · 0 of 6 parts rated
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