Genes and Other Things 2

Task 1: Read the passage below and then make up a title for this part of ‘Genes and other things’.

Title __________________________________________________________

Two scientists, Francis Crick and James Watson, finally began to find out the basics of how genes worked and how they copied themselves. This was back in 1953 when they discovered what the stuff that makes all genes everywhere really looked like. This stuff is called DNA (that stands for deoxyribonucleic acid ) and it looks like a double corkscrew. It seems that DNA is like a cassette tape which stores all the information about how to make a new cell - or person or any other living thing. It all coils up very small to pack away into the tiny space in the centre of cells.

How does the DNA copy itself? Because it's made of two corkscrews - called a double helix - hooked together, it can unwind. As it does this, it attracts the right new bits to join the hooks which run down its middle - a bit like the legs on a millipede. In this way, a single strand rebuilds a new mirror-image of itself, just as its mirror-image partner is doing nearby. In this way, one DNA molecule becomes two perfect copies.

How the DNA itself then organizes all the stuff inside a cell to make whatever it needs - like proteins - is complicated. Scientists still don't understand all the things that have to happen to make what starts as just one cell into a human being, or a whale, or any other living thing. It's taken 3,500 million years for nature to develop all this wonderfully clever yet tiny machinery to build bodies; therefore it's not surprising that scientists don't understand everything yet. This makes the next bit rather worrying.

Genes are long bits of DNA which code the instructions to build bodies in certain ways. Scientists know a lot about how genes work. They know how to 'snip' genes out of one place and 'stick' them into another. This is the hi-tech world of genetic engineering.

Task 2: Make four questions (one from each paragraph). Make sure the answer is contained in the text.

Task 3: What is each paragraph about?

The topic of paragraph 1 is___________________________________

The topic of paragraph 2 is___________________________________

The topic of paragraph 3 is __________________________________

The topic of paragraph 4 is__________________________________

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