Spot the one that does not belong

Exercise and reference answers

Questions

1. Items

   1. Amino group
   2. Phosphate group
   3. Carboxyl group

   Odd item

   Phosphate group

2. Items

   1. α-carbon
   2. R group
   3. Nucleotide

   Odd item

   Nucleotide

3. Items

   1. Always identical
   2. Twenty in proteins
   3. Substituted methanes

   Odd item

   Always identical

Explanation