Unit 2 – Evolution – Review KEY
1. Objective Page
2. Lamarck:
 Use or disuse
 Acquired a trait in your lifetime you could pass it on
 Not completely accurate or faulty
Darwin: “Father of Evolution”
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Variations
More offspring – compete and struggle
Survival of the fittest
Natural selection
3. Evidence of Evolution:
 Fossils – impressions/remnants of ancient organisms, use
fossils to show how an organism or species change over
time.
 Homologous structures – same structure but different
function, ex: batwing, human arm, flipper, show connections
to common ancestor.
 Vestigial Structures – ex: appendix, no longer in use,
connected to the past.
 Embryology – embryo study, if embryos look the same then
they must share a common ancestor.
 Biochemical Comparisons – ATP used, DNA language the
same.
 Widespread distribution of Org. – some organisms come to
look the same due to the same environmental pressures –
convergence.
 Analogous Structures – same function, different bones
(structures), ex: dragonfly – bird wing
4. Gene – part of a chromosome and controls traits.
5. Body Cells – somatic cells – 46 chromosomes
Sex Cells – gametes (sperm/egg) – 23 chromosomes
6. Homozygous – same alleles, purebred – BB or bb
Heterozygous – different alleles, hybrid – Bb
Selective Advantage – you have an advantage over others to be
selected.
7. Genotype – genes/alleles – Bb
Phenotypes – physical appearance – brown eyes
Monohybrid Cross
Segregation
X B B
B BB Bb
b Bb bb
P = parents
Bb X Bb
F1 Generation
Genotypic Ratios – 25% BB: 50% Bb: 25% bb
or 1BB: 2Bb: 1bb
Phenotypic Ratios – 75% brown: 25% blue
or 3 brown: 1 blue
Punnett Square –
chance or probability
of an occurrence.
P = RrYy X RrYy
Use foil = first
outside
inside
last
8. Law of Segregation: Mendel's Law of Segregation states that every
organism has two alleles per trait and that these alleles separate
during meiosis, so each gamete gets one allele.
9. Reproductive Isolation: isolating mechanisms
 Behavioral – act differently, ex: mating dance
 Time/ Temporal – different mating season
 Geographical – physically separated, ex: mtn or island
 Ecological – different habitats, ex: desert verses arctic
10.
Gradualism – gradual change in species, SLOW
Punctuated Equilibrium – slow and steady is interrupted
with a rapid change, ex: asteroid and mass extinctions
11.
Father of Taxonomy = Linnaeus
2 name naming = binomial nomenclature
(genus and species)
12.
Domain
Kingdom
Phylum
Class
Order
Family
Genus
Species (most natural)
13.
Dichotomous Key:
14.
3 DOMAINS:
D
Bacteria
Archae
Eukarya
K
Eubacteria
(cell wall, pep)
Archaebacteria
(cell wall, no pep)
Animali, Fungi,
Plantae, Protista
15.
Molecular Clock:
 Neutral mutations happens regularly
 Use these mutations to group organisms
 Same mutations they are more closely related
16.
Phylogeny – study of evolutionary relationships among
organisms.
Example: African Vulture………..American Vulture………..…Stork
Physically same
Genes are closer matched
Phylogenetic Tree: is a Cladogram diagram
Paraphyletic (some)
Monophyletic (one
common ancestor)
((one common
ancestor)
Polyphyletic (does not
include common
ancestor)