Module 2 - Gene Action & Inheritance

Mitosis

The process of cell division that results in two genetically identical daughter cells, each with the same number of chromosomes as the parent cell.

Meiosis

A type of cell division that reduces the chromosome number by half, resulting in four genetically diverse gametes, essential for sexual reproduction.

Genotype

The genetic constitution of an organism, which determines its traits and characteristics.

Phenotype

The observable physical or biochemical characteristics of an organism, as determined by both genetic makeup and environmental influences.

Allele

One of two or more alternative forms of a gene that arise by mutation and are found at the same place on a chromosome

Gene

A segment of DNA that contains the instructions for producing a specific protein or functional RNA.

The Principle of Segregation

The principle stating that during the formation of gametes, the two copies of each gene segregate, so that offspring receive one copy from each parent.

Independent Assortment

The principle stating that alleles of different genes assort independently of one another during gamete formation, contributing to genetic variation.

Frameshift Mutation

A type of mutation caused by insertions or deletions of nucleotides that alters the reading frame of the gene, potentially leading to a completely different protein.

Transcription

The process by which the genetic information in DNA is copied into messenger RNA (mRNA), which then directs protein synthesis.

Translation

The process by which the sequence of nucleotides in mRNA is decoded to synthesize a specific polypeptide or protein, occurring at the ribosome.

Initiation

The first stage of transcription and translation, where the assembly of the transcription complex or ribosomal subunits occurs, setting the stage for RNA synthesis or protein formation.

Elongation

The stage in transcription and translation during which the RNA strand or polypeptide chain is elongated as nucleotides or amino acids are sequentially added to the growing polymer.

Termination

The final stage of transcription and translation when RNA polymerase or the ribosome releases the completed RNA or polypeptide, respectively, signaling the end of the synthesis process.

Intron

Non-coding sequences in a gene that are transcribed into RNA but removed during RNA splicing before translation.

Exons

The coding regions of a gene that are transcribed into mRNA and translated into protein, separated by non-coding regions called introns.

Transcription Activators

A protein (transcription factor) that increases transcription of a gene or set of genes