Key Idea: DNA molecules provide the cells with instructions for assembling protein molecules from amino acids.

Students are expected to know that:

  1. Protein molecules are made up of amino acid subunits linked together in a specific sequence.
  2. DNA molecules provide instructions for linking and ordering amino acids to form protein molecules.
  3. Each sequence of three nucleotides in a molecule of DNA codes for an amino acid.
  4. The set of nucleotides in a DNA molecule that provide instructions for assembling a particular protein molecule from amino acids is called a gene.
  5. 20 different types of amino acids are used to make protein molecules.
  6. A change to the sequence of nucleotides in a gene within a molecule of DNA can alter the protein that is produced.
  7. Changes to the sequence of nucleotides in a molecule of DNA can come from insertions, deletions, or substitutions of one or more nucleotide subunits in a DNA molecule.
  8. Changes to the sequence of nucleotides in a molecule of DNA are called mutations.

Boundaries:

  1. Students are not expected to know the terms: transcription, translation, messenger RNA, transfer RNA, codons, or anticodons.
Frequency of selecting a misconception

Misconception
ID Number

Student Misconception

Grades
6–8

Grades
9–12

RHM128

Amino acids provide instructions for making proteins in an organism (AAAS Project 2061, n.d.).

36%

44%

RHM101

Four types of amino acids are used to make protein molecules (AAAS Project 2061, n.d.).

37%

43%

RHM065

The information in genes provides instructions for rearranging DNA into traits (AAAS Project 2061, n.d.).

40%

33%

RHM064

The information in DNA molecules provides instructions for rearranging genes into traits (AAAS Project 2061, n.d.).

41%

29%

RHM063

Four nucleotides are needed to code for one amino acid (AAAS Project 2061, n.d.).

32%

35%

RHM100

Three types of amino acids are used to make protein molecules (AAAS Project 2061, n.d.).

35%

27%

RHM066

The information in genes provides instructions for assembling chromosomes into DNA (AAAS Project 2061, n.d.).

31%

31%

RHM062

DNA is made of amino acids (AAAS Project 2061, n.d.).

29%

29%

RHM129

Enzymes provide information for making proteins in an organism (AAAS Project 2061, n.d.).

26%

24%

RHM127

An organism makes proteins from individual carbon, oxygen, hydrogen, and nitrogen atoms (AAAS Project 2061, n.d.).

29%

19%

RHM009

DNA is made of protein (Marbach-Ad, 2001).

20%

17%

RHM010

Proteins are composed of DNA or genes (Marbach-Ad, 2001).

19%

15%

RHM044

Organisms eat proteins; they do not make them (AAAS Project 2061, n.d.).

21%

10%

Frequency of selecting a misconception was calculated by dividing the total number of times a misconception was chosen by the number of times it could have been chosen, averaged over the number of students answering the questions within this particular idea.