Task 1. Read the text. For questions 1-10 mark the statements as T (true), F (false) or DS (doesn’t say).
It’s in our DNA
In every cell of the human body there is almost two metres of genetic information that is tightly packed into pieces called chromosomes. Humans have 46 chromosomes – 23 from each parent. These chromosomes contain coding for approximately 25,000 genes. However, this only accounts for a small amount of the 3 billion nucleotides in our DNA sequence. The rest are not thought to code. It is the information in these genes that determine many of our characteristics, for example: eye colour, hair colour, hair type, shoe size, height and many more.
In the 1850s and 1860s, a scientist called Gregor Mendel was very curious about how exactly we inherit characteristics from our parents. At the time, people believed that our parents’ characteristics were combined to create new characteristics. However, we now know that this isn’t the case. Mendel conducted experiments using pea plants to investigate exactly how genes are passed down from generation to generation.
Gregor Mendel discovered that each gene has more than one variation and these variations are called alleles. For instance, the gene for eye colour has two main alleles; brown and blue. Gregor also discovered that some alleles are stronger than others. The stronger alleles are known as dominant and the weaker ones as recessive. He recorded the characteristics in the peas and used them to calculate how many offspring would display dominant or recessive traits. Mendel used mathematical statistics to work out what characteristics the offspring of parents with known alleles would have.
Mendel’s presented his findings in 1865 but they weren’t accepted by the scientific community at the time and the importance of his work wasn’t recognised until years after his death. It is thanks to Mendel’s work that geneticists today can predict the likelihood of genetic diseases or certain characteristics in children. This helps parents be aware of how likely it is they will pass on certain conditions and traits to their children. This in turn has paved the way to modern techniques such as gene editing and the future possibility of designer babies.
1 . Each chromosome is around two metres in length. ……
2. Only humans have a total of 23 pairs of chromosomes .……
3. All of our nucleotides code for characteristics. ……
4. People believed the genes from each parent were mixed together. ……
5. Mendel discovered that there is one allele for each gene. ……
6. Recessive alleles aren’t as strong as dominant ones. ……
7. Mendel spent years doing research before presenting his findings. ……
8. People accepted Mendel’s findings before he died. ……
9. Parents can find out what chance they have of passing on a disease. ……
10. Mendel’s work has contributed to today’s genetic techniques. ……

Task 2. Choose the correct answer.

1 The earthquake ….. off the coast.
A struck C exceeded
B shook D hurled

2 Let’s ….. out of the car now before we are swept away by the floodwater.
A to get C getting
B get D gets

3 I can’t stand ….. the news about the forest fire. It’s just too upsetting.
A watch C to watching
B to watch D watching

4 There is a flood warning in my city because one of the rivers ….. its banks.
A flooded C broke
B collapsed D burst

5 I regret ….. you that your flight is cancelled due to the storm.
A to tell C tell
B telling D told

6 He would like ….. a rescue worker in the future to help those affected by natural disasters.
A become C to become
B becoming D becomes

7 The ….. of a tsunami wave is so powerful that it can destroy even the strongest buildings.
A crash C collision
B ripple D impact

8 I can’t believe they found a ….. baby under the rubble.
A 6-month-old C 6-months-olds
B 6-months-old D 6-month-olds

9 A great way to protect your home from flooding is to build flood ….. such as barriers and walls.
A levees C defences
B dams D shelters
10 Working as part of an emergency team, you are responsible ….. helping survivors.
A in C to
B for D of

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