Each structure is one of the 20 standard amino acids. Translate its one-letter code, then type the five-letter word.

Word set
Structure style
Time 00:00.0

The molecules and answer boxes are hidden until you start.

The timer begins when you select Start.

Identify each amino acid, then enter its one-letter code.

CarbonHydrogen NitrogenOxygen Sulfur

Help

How to play

  1. Identify the amino acid shown in each image.
  2. Enter its one-letter code in the box below it.
  3. Select Check word to submit all five letters.
Structure style
Choose line, ball-and-stick, or PubChem 3D images. Mixed chooses a style at random.
Timer
The timer starts when you select Start and stops when you submit the word.
Results
Correct letters and incorrect letters are marked separately. The correct word is shown after you submit.
Daily word
Everyone gets the same daily word. You can submit it once each UTC day, then continue with random practice.
Missed-acid practice
When you are signed in, missed amino-acid codes are saved. Choose Practice missed acids to get words containing as many of those codes as possible.

Reference

The 20 standard codes

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