b2 Flashcards
prezygote/ before the zygote/ mating
prevents fertilization
habitat isolation
type of prezygotic factor
species live in different areas that’ll never meet so they don’t mate
eg. land snake vs water snake
mechanical isolation
physical attributes prevent mating
behavioural isolation
rituals to attract mates, sometimes doesn’t work
sources of genetic variation
mutations: change in dna, random
sexual reproduction: mom and dad mix alleles to make combination
asexual reproduction: cloning ur genes lmfao what
why is genetic diversity important
rich ecosystem
better for adaptation
lamarks theory
parts of body’s are used more than others
they grow stronger and bigger
gets passed down to offsprings
not really accurate lmfao
darwin’s theory
theory of natural selection
those who are the best fit for the weather/ season/ conditions will live
evidence of evolution: fossils
most direct evidence of evolution
evidence of evolution: biogeography
geography in the past and present
species who are similar but live in different places were close to each other geographically
evidence of evolution: anatomical
comparing species bone structure to find similar ancestor
eg. finding similar useless bones between 2
evidence of evolution: embryological
comparing embryos
similarities between fertilized cells and growth
evidence of evolution: bio chemical
dna and chromosomes similarities means more closely related
evidence of evolution: artificial selection
similar plants share breeding ancestor
gradualism
gradual adaptive features change slowly overtime
punctuated equilibrium
changes in species are quick
eg. bird gizmo
patterns of speciation
there are 2 ways speciation can happen:
1. transformal evolution where species are mutating and adapting to environmental changes
2. a species branch out to 2 different species
temporal isolation
species breed at diff times of year
gametic isolation
female don’t like some male sperm lmfao
homologous
species have similar structures and ancestor, but not function
eg. dog and human muscle
analogus
species have similar functions, but no common ancestor and different structure
eg. bird, bat, butterfly
darwin observations
population no grow
food and resources are competed for
variation between species
more offspring than can survive
variations are heritable
darwin inferences
