Mi-STAR Unit 8.1 Lesson 3: Genes, Proteins, and Mutations

A set of vocabulary flashcards defining key genetics concepts, proteins, mutations, and experimental examples from Mi-STAR Unit 8.1 Lesson 3.

Gene

A sequence of DNA that determines the structure of a protein; the combination of genes on the chromosomes determines which proteins are made in the cell.

Protein

Large, complex molecules that make up structural components of body tissues and are responsible for most of the functions, chemical reactions, and traits in living cells.

Mutation

A random and permanent change to genetic material in a gene, which occurs rarely in nature.

Trait

A characteristic an organism inherits from its parents, which can be observable (such as height, eye color, and hair curliness) or not obvious (such as bone strength, lactose intolerance, and red blood cell shape).

Genetic Code

A living cell's instructions, composed of a series or sequence of DNA molecules, for how to build different proteins.

Protein Structure and Function Relationship

The biological principle that the sequence of a gene determines the shape (structure) of a protein, and changes to this structure alter the protein's function and the resulting traits of an organism.

Gatekeeper Protein

A specific bed bug protein whose structure determines how individuals react to insecticide, including whether they can survive exposure.

Invade

An insecticide whose active ingredient targets bed bugs based on the structural fit of their gatekeeper protein.

Blue Eyes Phenomenon

An evolutionary event occurring approximately $10,000$ years ago when the first blue-eyed individual was born to brown-eyed parents due to a genetic mutation that altered protein structure and trait outcome.

Human Gene Count

The total number of genes in humans, approximately $19,000$, each responsible for producing a different protein.

Natural DNA Copying Accuracy

The high fidelity of cellular replication in nature, where organisms have only about a $0.0000001\%$ chance of error per letter, leading to only about $30$ to $64$ mutations across $3,000,000,000$ DNA molecules passed to offspring.

OS-1 Protein

A simulated model protein whose functions are to stick to an organism's cell membrane and provide strength and flexibility to its cells.

Ancestor OS-1 Genetic Code

The initial baseline sequence of six letters—$\text{S-P-L-B-S-B}$—used in the simulation to model asexual transmission and copying mistakes across generations.

Flowchart of Trait Formation

A step-by-step model showing that a Random Event (dice roll or mutation) changes Genetic Code, which changes Structure of a Protein, which changes Function of a Protein, which ultimately changes Traits.

Rock Pocket Mouse

A small mammal found in the southwestern United States and Mexico that generally has light-colored fur matching rocky terrain, but occasionally produces dark-colored fur due to a mutation.