Semester Test Flashcards
Directional selection
picking one side of trait(usually extreme) like giraffe necks
Stabilizing selection
when organisms in the average survive more; like kittens,runts die
Disruptive selection
often reason for species change (both extremes prevail)
Difference between evolution and intelligent design
evolution= random acts I.D= a god designed the universe
Sexual selection
females drive evolution= they pick males that are the biggest, strongest, healthiest
like peahens and peacocks
artificial selection
when humans pick traits; ex: dog breeding
how is mutation caused
when base pairs don’t match up; they are sometimes good
Heterozygous-
has a dominant and recessive alle
Homozygous
2 dominants or 2 recessive
Dominance
- ability of an alle to dominate over another (override)
recessive
requires another recessive alle to show its trait.
What is the double helix made of
Phosphate, and sugar groups make up the nucleotide double helix; bases with 4 nucleotides.
WHAT are the base pairs on a double helix? DNA
A &T are base pairs, and G &C are base pairs
WHAT ARE BASE PAIRS HELD TOGETHER
hydrogen bonds
Homologous structures
similar in arrangement or function or both
