Definitions Flashcards
Epigenetics
Preference changes in the expression of genes that are already present, that bring about change in a bahaviour
Broad sense heritability
Proportion of variance in phenotype due to genetic variation
H2 = (VG/(VG+VE)
Broad sense heritability (VG= Genotype variance, VE= Environmental variance)
Narrow sense heritability
Proportion of total phenotypic variation that is due to the additive effects of genes
H2 = (VA/(VA+VE)
narrow sense heritability
Central DOGMA
The genetic flow of information from DNA, to mRNA, to proteins.
Genome
Entirety of an organism’s hereditary information
Exon
Coding region of a gene
Intron
Region of a gene that is not translated into proteins
Intergenic regions
“junk DNA” between genes; some regulatory functions
1) Replication
1st stage of protein synthesis: where DNA replicates into 2 identical copies
2) Transcription
2nd stage of protein synthesis: Making a complementary RNA copy of a DNA sequence (U replaces T)
3) Translation
3rd stage of protein synthesis: amino acid chain created from mRNA
2a) Splicing
Removes introns and joins exons during protein synthesis
Horizontal memory
Cells made for your own body
Vertical momory
Cells inter-generationally transferred
Chromatin
complex form of DNA and protein in eukaryotes
Histones
Major proteins, highly alkaline
Euchromatin
lightly packed form of DNA
Heterochromatin
tightly packed form of DNA; repetitive with few coding regions
Genomic Imprinting
Silencing of one parental copy of DNA
X-Silencing
Turning off expression of 1 X-Chromosome to prevent double quantities
Catch-Up Growth
Poor childhood growth and then a better boom can worsen condition
The 1992 Thrifty Phenotype Hypothesis
Cutting corners allow offspring to survive there and then; right here right now approach
Predictive Adaptive Response
Environment is acting on early development, with phenotypic consequences beneficial for future reproduction
Survival advantage in predicted reproductive environment
Plasticity
Ability to generate multiple phenotypes from a single genotype
Developmental Pasticity
Irrepareable change in phenotype depending on early development (liver cells stay as liver cells)
Behavioural plasticity
Interchangeable phenotypes that aren’t ‘stuck’
Neoteny
Somatic growth is slowed (adult in child’s body)
Progenesis
Hastened reproductive development (Normal growth, early reproductive organs)
Heterochrony
Change in the time of key events in your development
The Modern Synthesis
Life evolves through evolution by natural selection (Huxley 1942)
Genetic assimilation
introduction of beneficial genes into existing selection on phenotypes.
Arises through developmental canalization (selection on a single outcome)