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Unit 1:
Ch. 1
Ch. 2
Ch. 3
Interlude A
Unit 2:
Ch. 4
Ch. 5
Ch. 6
Ch. 7
Ch. 8
Ch. 9
Interlude B
Unit 3:
Ch. 10
Ch. 11
Ch. 12
Ch. 13
Ch. 14
Ch. 15
Interlude C
Unit 4:
Ch. 16
Ch. 17
Ch. 18
Ch. 19
Interlude D
Unit 5:
Ch. 20
Ch. 21
Ch. 22
Ch. 23
Ch. 24
Ch. 25
Interlude E

22nd Amino Acid Discovered: Comment from University of Utah

Science, 24 May 2002

The discovery of a 22nd amino acid indicates that life's genetic code is richer than once thought and that scientists may be able to manipulate the code to make new industrial enzymes, University of Utah geneticists say.

» Read the full article

Active Reading Questions

  1. Amino acids are the building blocks of
    a) carbohydrates.
    b) fats.
    c) proteins.
    d) nucleic acids.
  2. Your book describes 20 amino acids that are biologically active. According to this article, how many genetically encoded amino acids are there?
    a) 20
    b) 21
    c) 22
    d) 26
  3. Explain how amino acids are linked to form proteins.
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