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Science (2015) Grade(s): 09-12 - Biology


Formulate an evidence-based explanation regarding how the composition of deoxyribonucleic acid (DNA) determines the structural organization of proteins.

Unpacked Content

Scientific and Engineering Practices

Engaging in Argument from Evidence; Obtaining, Evaluating, and Communicating Information

Crosscutting Concepts



Students know:
  • All living things have DNA How the 5' and 3' orientation of DNA nucleotides results in the antiparallel nature of DNA.
  • The complementary nature of nitrogenous bases.
  • How hydrogen bonding holds complementary bases together across two DNA strands.
  • The basic mechanism of reading and expressing genes is from DNA to RNA to Protein (The Central Dogma of Biology).
  • The first step of the Central dogma is a process called transcription, which synthesizes mRNA from DNA.
  • The process where the mRNA connects to a ribosome, the code is read and then translated into a protein is called translation.
  • To become a functional protein, a translated chain of amino acids must be folded into a specific three-dimensional shape.
  • Historically important experiments that led to the development of the structure of DNA, including Mieshcer, Chargraff, Rosalind Franklin, Watson/Crick, etc.
  • DNA changes can be linked to observable traits in the natural world, such as diseases.
  • Common laboratory techniques are used to obtain evidence that supports the premise that DNA changes may affect proteins and in turn the appearance of traits.
  • Types of errors that can occur during replication and the impact these errors have on protein production and/or function.


Students are able to:
  • Build from scratch or work with previously constructed models of DNA to identify the key structural components of the molecule.
  • Obtain and communicate information (possibly through a conceptual model) describing how information encoded in DNA leaves the nucleus.
  • Obtain and expand explanation to include how the information transcribed from DNA to RNA determines the amino acid sequence of proteins.
  • Identify and describe the function of molecules required for replication and differentiate between replication on the leading and lagging DNA strands.
  • Group mRNA into codons and identify the amino acid associated with each codon. Create and manipulate polypeptide models to demonstrate protein folding.
  • Use a variety of resources (web-based timelines, original publications, documentaries, and interviews), explain how historically important experiments helped scientists determine the molecular structure of DNA, and develop the concept of the Central Dogma of Biology.
  • Analyze a variety of diagnostic techniques that identify genetic variation in a clinical setting.
  • Relate protein structure to enzyme function and discuss the causes and impacts of protein denaturation on both enzymes and structural proteins.
  • Identify the impact of DNA changes on the structure and/or function of the resulting amino acid sequences.
  • Predict the impact of errors during DNA replication in terms of protein production and/or function.
  • Classify types of DNA changes (deletions, insertions, and substitutions).
  • Use models to explain how deletions, insertions, translocation, substitution, inversion, frameshift, and point mutations occur during the process of DNA replication.


Students understand that:
  • The traits of living things are ultimately determined by inherited sequences of DNA.
  • The end product of transcription is always RNA, but the process produces many different types of RNA with varying functions.
  • DNA instructions are replicated and passed from parent to offspring, segregating traits across generations in a mathematically predictable manner.
  • A protein is a linear sequence of amino acids that spontaneously folds following rules of chemistry and physics.
  • A series of historically important experiments let to the current understanding of the structure of DNA and the Central Dogma of Biology.
  • Errors that occur during DNA replication can affect protein production and/or function. Important projects over the past 30 years have changed the definition of a "gene" and increased the ability to assess the impact of DNA variation in a trait or disease.
  • Genetic change can lead to altered protein function and the appearance of a different trait or disease.


  • Nitrogenous bases
  • Deoxyribose
  • Phosphates
  • Hydrogen bonding
  • Nucleotides
  • Semi-conservative replication
  • Central Dogma
  • Transcription
  • Various types of RNA, including those involved in protein synthesis (mRNA, tRNA & rRNA) and those associated with gene regulation (e.g., IncRNA, miRNA, siRNA) and post-transcriptional modification (snRNA)
  • RNA polymerase
  • Introns
  • Exons
  • Codon
  • Translation
  • Anticodon
  • Deletion
  • Insertion
  • Substitution
  • Variant
  • DNA sequencing
  • PCR
  • Gel electrophoresis
  • Big Science Projects conducted over last 30 years: Human Genome Project, The International Hap Map, ENCODE, Cancer Genome Atlas, 1000 Genomes project, ClinVar and ClinGen, and the Exome Aggregation
  • Consortium.
  • Deletion
  • Insertion
  • Translocation
  • Substitution
  • Inversion
  • Frameshift mutations
  • Point mutations