New Science Standards: Spot the patterns!

The Next Generation Science Standards (NGSS) Are Coming Soon. But the story started long ago...

Ideas that form the Next Generation Science Standards have been around for centuries.

In the 1940s a biochemist named Erwin Chargaff analyzed the DNA of many different species of animals and plants. He soon spotted a pattern.

DNA was mostly made of 4 nitrogen based molecules known as nucleotides. Chargaff noticed that two nucleotides, adenine and thymine, always existed on a 1:1 ratio in the DNA of every organism he studied. Likewise, the ratio of guanine to cytosine was always 1:1 or very close.

He didn't realize what this meant, but he noticed the pattern.

Several years later, James Watson and Francis Crick took a look at Chargaff's data. They had been puzzling over the structure of DNA. They knew the four nucleotides had to fit together in a smooth way. They had strong evidence that they fit together in a spiral shape (a helix). But there was a nagging problem.

Two of the nucleotides, adenine and guanine, are in a group of chemicals called purines. They occupy almost twice as much space as thymine and cytosine, which are in a group called pyramidines. How could these different-sized molecules fit together without creating bumps and kinks in the spiral?

The pattern that gave the answer.

Finally, Watson and Crick saw the answer in Chargaff's work. The reason there were equal amounts of adenine (a purine) and thymine (a pyramidine): the big molecule would link with the small one! In this way, every pair of nucleotides would be even.

Today, every student of biology learns Chargaff's rules. A binds with T, C binds with G. This discovery has lead to the understanding of RNA, protein synthesis, reproduction, etc. It has enabled breakthroughs in forensics, medicine, and a deeper understanding of the history of life on earth.

Chargaff never got the full credit he deserved, but we are indebted to his ability to recognize patterns.

Next Generation Science Standards: Coming soon to a school near you.

In just the past few months, a vast team of scientists, government officials and educators drafted a new science curriculum for schools throughout the United States.

The new guidelines of the "Next Generation Science Standards" include seven "Crosscutting Concepts" that are vital to every branch of science. The first of these is patterns. In the near future, students will be required to hone their skills at pattern recognition.

But there's more at stake than grades, college admission, or even the double helix structure of DNA. Scientists and engineers rely on patterns and look for them every day.

Come to think of it, patterns have important implications in sports, driving, finance, music, and really almost any career you can think of.

No wonder they are a part of the Next Generation Science Standards. Do you detect a pattern here?

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