Concept 23 A gene is a discrete sequence of DNA nucleotides.
Fred Sanger (middle) at age 11 with his older brother and younger sister.
Fred Sanger and his wife, 1940.
Fred Sanger at a 1949 Cold Spring Harbor Symposium meeting.
Fred Sanger, late 1940's.
Fred Sanger in his lab, late 1950's. He is looking at sequencing results.
Fred Sanger at his second Nobel Prize ceremony, 1980.
The chemistry of the sequencing method used in sequencing projects like the Human Genome Project is the same as that developed by Fred Sanger. However, with current technology, it is possible to read up to 500 nucleotides per reaction.
There is a limit of how many nucleotides can be read from a sequencing reaction. Why? What is the limiting factor?
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Fred Sanger (middle) at age 11 with his older brother and younger sister.
DNA and proteins are key molecules of the cell nucleus.
One gene makes one protein.
A gene is made of DNA.
Bacteria and viruses have DNA too.
The DNA molecule is shaped like a twisted ladder.
A half DNA ladder is a template for copying the whole.
RNA is an intermediary between DNA and protein.
DNA words are three letters long.
A gene is a discrete sequence of DNA nucleotides.
The RNA message is sometimes edited.
Some viruses store genetic information in RNA.
RNA was the first genetic molecule.
Mutations are changes in genetic information.
Some types of mutations are automatically repaired.