U3 Terms Flashcards
Recombination
Moves mutations around to different copies of a chromosome
Independent Assortment
Influences how chromosomes get packaged into gametes
Mutations are the…
and they… (3 things)
“Variation factory”
1) Occur randomly
2) Are found in everyone
3) Can be good, bad, or neutral
Production of new variation CANNOT… (2)
1) Be stopped
2) Be predicted
Natural Selection
Heritable variation being transmitted and sorted differently based on different environments
Components of Natural Selection (3)
1) Production (heritable variation)
2) Transmission (heredity)
3) Sorting (survival/reproduction)
Types of Selection
1) Stabilizing selection
2) Directional selection
3) Disruptive selection
Stabilizing Selection
(Bell curve gets skinnier: removing the variance at both extremes)
–> Variance decreases
–> Mean peak (most common phenotype) stays the same
Directional Selection
(Bell curve moves towards one side)
–> Mean value of the character (most common phenotype: the peak) changes
–> Causes the removal of one of the extremes (the one shifting away from)
Disruptive Selection
(Bell curve peak is disrupted)
–> Variance increases
–> Extremes increase
–> Medium variants become less common and the extremes become more common
Mutations are…
Random
Natural selection is…
NON-random
Sexual Dimorphism
The systematic difference in form between individuals of different sex within the same species
The environment does NOT ______ mutations
cause
Environmental change or the need to adapt CANNOT….
Change or force the variation factory to produce different/specific variation
Sexual Selection
Explains the patterns in which there is variation between the sexes in a single species
(Why different species have different types of sexual dimorphisms)