Micro - Chapter 9 Genetics

Genetic Code

The information in a cell that determines metabolic capabilities, toxins produced, and mechanisms for invading and evading the immune system.

Genome

The complete set of genetic material in a cell, including chromosomes and plasmids.

Plasmids

Small circular DNA molecules that carry genes for nonessential functions such as antibiotic resistance.

Chromosomes

Cellular structures that carry hereditary information and contain segments of DNA that code for functional products.

DNA Replication

The process by which a cell copies its genome to provide each daughter cell with a complete set of DNA.

Central Dogma of Molecular Biology

The process of DNA being transcribed to RNA and translated into protein (DNA -> RNA -> Protein).

Transcription

The process of copying a gene from DNA into mRNA.

Translation

The process where mRNA is used as a template to synthesize proteins.

Operon

A group of genes that are transcribed together as a unit; examples include the lac and trp operons.

Inducible Operon

An operon that is usually off but can be turned on when needed, such as the lac operon.

Repressible Operon

An operon that is usually on but can be turned off when there is excess product, such as the trp operon.

Phenotypic Variation

Changes in an organism's phenotype due to environmental influences that regulate gene expression.

Gene Transfer

The mechanism by which genetic diversity is generated in bacteria, including transformation, transduction, and conjugation.

Transformation

The uptake of naked DNA by a competent bacterium.

Conjugation

The transfer of genes through direct contact between live donor and live recipient bacterial cells.

DNA Repair

Mechanisms that fix damaged DNA, including base-excision repair and mismatch repair.

Mutation

A change in the DNA sequence that can lead to changes in the mRNA and protein synthesis.

Mutagens

Agents that cause mutations, such as certain chemicals and radiation.

Horizontal Gene Transfer

The transfer of genetic material between organisms of the same generation.

Vertical Gene Transfer

The transfer of genetic material from parent to offspring.

Circular DNA

The structure of bacterial chromosomes, allowing for unique replication processes.