Chapter 16: How Genes Work

This set of flashcards focuses on vocabulary related to the topic of gene function, mutations, and the molecular biology concepts covered in the lecture.

one-gene, one-enzyme hypothesis

The hypothesis asserting that each gene encodes a specific enzyme.

Mutant

An organism that has undergone a mutation and may exhibit a change in phenotype.

Transcription

The process of making a copy of information from DNA to mRNA.

Translation

The process of interpreting the mRNA sequence into a polypeptide chain of amino acids.

Point mutations

Mutations that result from a change in a single nucleotide base.

Chromosome mutations

Larger-scale mutations that affect chromosome structure or number.

Phenotype

The observable traits of an organism, determined by the proteins produced.

Genotype

The genetic constitution of an organism, represented by its DNA sequence.

Central dogma

The framework describing the flow of genetic information from DNA to RNA to protein.

Beneficial mutations

Mutations that increase an organism's fitness or ability to survive.

Nonsense mutation

A mutation that results in an early stop codon, leading to truncated proteins.

Silent mutation

A mutation that does not change the amino acid specified by a codon.

Frameshift mutation

A mutation caused by insertions or deletions in the DNA sequence that alters the reading frame.

Reverse transcriptase

An enzyme that converts RNA into DNA, found in retroviruses like HIV.

Genetic code

The set of rules by which information in DNA and RNA is translated into proteins.

Universal genetic code

The notion that the genetic code is nearly the same across all life forms.

Mutations

Permanent changes in an organism's DNA that can alter gene function.

Neurospora crassa

A type of bread mold used in genetic experiments to study mutations and metabolic pathways.

Missense mutation

A point mutation that results in a codon that codes for a different amino acid.

Codon

A sequence of three nucleotides in mRNA that specifies a particular amino acid or a stop signal during protein synthesis.

Anticodon

A sequence of three nucleotides in tRNA that is complementary to a codon in mRNA, ensuring the correct amino acid is brought to the ribosome.

Ribosome

A complex molecular machine found within all living cells that serves as the site of biological protein synthesis (translation).

mRNA (messenger RNA)

A type of RNA that carries the genetic information from DNA in the nucleus to the ribosomes in the cytoplasm, where it serves as a template for protein synthesis.

tRNA (transfer RNA)

A type of RNA molecule that helps decode a messenger RNA (mRNA) sequence into a protein. tRNAs function at specific sites in the ribosome during translation, which is a process that synthesizes a protein from an mRNA molecule.