chapter 17

Gene

The basic unit of heredity transferred from parent to offspring, defined as a DNA sequence producing a functional product.

Central Dogma of Biology

The flow of genetic information from DNA to RNA to protein through replication, transcription, and translation.

Transcription

The process of synthesizing messenger RNA (mRNA) from a DNA template.

Translation

The process of synthesizing polypeptides from messenger RNA (mRNA) at ribosomes.

Codon

A sequence of three nucleotides in mRNA that codes for a specific amino acid.

Mutations

Changes in the DNA sequence that can produce genetic variation.

Point Mutation

A mutation that involves a single nucleotide change in the DNA sequence.

Sickle-cell Anemia

A disease caused by a point mutation in the hemoglobin gene leading to abnormal red blood cell shape.

mRNA

Messenger RNA that transports amino acid codes from the nucleus to ribosomes for protein synthesis.

tRNA

Transfer RNA that brings amino acids to ribosomes based on mRNA codons.

rRNA

Ribosomal RNA that forms a structural component of ribosomes.

64 codons

The total number of codons coding for 20 amino acids, allowing redundancy in the genetic code.

RNA Polymerase

The enzyme that unwinds DNA and synthesizes mRNA during transcription.

Evolution

The process through which genetic variation, including mutations, can contribute to adaptation of species.