Scientific and Engineering Practices
Engaging in Argument from Evidence; Obtaining, Evaluating, and Communicating Information
- 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
- Hydrogen bonding
- Semi-conservative replication
- Central Dogma
- 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
- DNA sequencing
- 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
- Frameshift mutations
- Point mutations