Genetics Flashcards
Define gene.
A heritable factor that consists of a length of DNA and influences a specific characteristic.
Define gene expression.
The process by which the information coded for in genes is used to create an mRNA transcript and then translate it into a protein that will influence the characteristics of a cell/organism.
Define allele.
An alternative form of a gene that codes for different variations of a specific trait.
Define gene locus.
The position of a gene on a chromosome.
Define genome.
The whole of the genetic information of an organism.
Define gene mutation.
Random changes in the alleles.
Define base substitution mutation.
One base in the DNA sequence changes & is replaced by another base. Most significant type of mutation.
Define plasmids.
Small extra DNA molecules that are commonly found in prokaryotes but very unusual in eukaryotes. Small, circular and naked, contain a few genes that may be useful to the cell but not needed for basic life processes.
Define homologous chromosomes.
Chromosomes that carry the same sequence of genes in the same locus but not necessarily the same alleles.
Define meiosis.
A reduction division where one diploid nucleus divides to form 4 haploid nuclei.
Define gamete.
A cell containing a haploid number of chromosomes.
Define bivalent.
A pair of homologous chromosomes.
Define synapsis.
The pairing process of bivalents.
Define crossing over.
The exchange of DNA material between non-sister chromatids, results in the production of chromatids with new combinations of alleles.
