BIOL 112 Exam 1

3 Rules of Science

1. without proof, one if just a loudmouth with an opinion
2. one time does not a pattern make
3. one must let others review scientific analysis and findings

Science

the discipline associated with data collecting and analysis that makes people think critically to answer questions and solve problems

Empiricism

Observable, can be measured

For every \________ gene, there are \________ alleles and \_______ genotypes

1:2:3

Hardy Weinberg Equations

p+q\=1
p^2+2pq+q^2

4 Types of Changes in Chromosome structure

1. Deletion
2. Duplication
3. Inversion
4. translocation

Evolution

speices change over time; dissent with modification

Why are fossils imporant?

1. shows organisms that were once here
2. can date rocks
3. fossils bridge the gap between extinct and extant

Nature is

NOT teleolgical

Teleoglical

has a plan/motive

Paradigm Shift

New Technology \---\>New Information \---\> New analysis \---\> paradigm shift

Darwin's 3 observations

1. unity of life
2. diversity of life
3. match between organisms and their enviorment

Connect the dots

-individuals vary
--too many individuals
\---certain individuals have greater reproductive success
\----natural selection
\-----dissent with modificaiton
\------evolution
\-------possibility of speciation

if an \_____ changes, natural selection may result in adaptation to these new conditions and may give rise to speciation

environment

Good example of evolution

drug resistant bacteria

T/F Natural Selection Creates?

False; it only edits

Homology

dissent from common ancestors

Natural Selection Acts on

individuals

only \_______ evolve

populations

Natural Selection Leads to

dissent with modficiation

Why don't the tail feathers of the male peacock continue to get bigger and bigger if the female peacocks tend to select for that trait

predation

Heterozygote Adanvatage

when heterozygotes have higher fitness than both homozygotes

Selection Types

frequency dependent selection

Biological Species Concpet

1. can interbreed
2. do interbreed
3. offspring are viable

Prezygotic Barriers

Habitat isolation
temporal isolation
behaviroal isolation
mechanical isolation
gametic isolation

Postzygotic Barriers

reduced hybrid viability
reduced hybrid fertility
hybrid breakdown

General Understanding of postzygotic barriers

-hybrids for short periods of time
-hybrids for long periods of time

Allopatric speciation

gene flow is interrupted;
when a population is divided into GEOGRAPHICALLY isolated subpopulations

The greater the barriers subdivide a region

the greater the degree to which speciation will occur

Hybrid Zone

a region in which member of different speices mate and produce hybrids

when closely related speices meet in a hybrid zone, there are 3 possible outcomes

1. reinforcement
2.fusion
3. stability

\____________________ separate from hybrid zones

postzygotic barriers

what occur when hybrids are LESS FIT THAN PARENT SPECIES

reinformcement of reproductive barriers

over time what descreases?

rate of hybridization

Fusion

two distinct species, the hybrid produced "overpowers" the parent species

when gene flow is great what happens?

reproductive barriers weaken and the parent species can FUSE INTO A SINGLE SPECIES

Reinforcement

parents interacting overlap in the zone

stability

interact for short period of time and leave; come into the zone then leave

Punctuated model

Intense and SUDDEN environmental change
(chapter 24 slide 121)

incommensurable

that which CANNOT be compared equally

macroevolutionary changes

1. the emergence of terrestrial vertebrates
2. the impact of mass extinctions
3. the origin of flight in bird

Conditions on early Earth that made the origin of life possible

1. abiotic synthesis
2. RNA before DNA
3. Protocells
4. Convergent Evolution
5. islands as laboratories
6. endosymbiotic theory

all elements on earth came from where?

outer space

\______________ is Single stranded (except in certain viruses) and is \______________

RNA; energetically favorable

what can become the blueprint to proteins (mRNA)

RNA

Properties of RNA

-single stranded
-enzymatic properties (ribozymes)

Which came first RNA or DNA

RNA

How did protocells form

from fluid filled vesicles with a membrane like structure

Phospholipid bilayers

-not linear
-elongate for micelles
-lead to protocells

\______________________ exhibit simple \_______________ and \_______________ and maintain an internal chemical enviorment

vesicles; reproduction and metabolism

Plasma Membranes

1. have the ability to separate internal environment from an external environment
2. channel things in and out

What happens when vesicles get too big?

sometime a piece pinches off and become a smaller vesicle within the bigger vesicle; it can then rapidly absorb RNA

Fossil record

1. sedimentary rock
2. mammals buried in ice
3. insects preserved in amber

Stromatolies

very old structures that have cynobacteria

Tiktaalik

lungs and gills, anatomy to survive outside of water

What is the oldest fossil evidence of life on this planet?

stromatolites

Trasitonary fossil that connects aquatic veterbrates to terrestrial verterbrate

Tikaalik

Is the fossil record biased or unbiased?

biased

The fossil record is biased in favor of species that

1. existed for along time
2. were abundant and widespread
3. had hard parts

Cynodont

a carnivorous mammal-like reptile of the late permian and triassic periods whose speicialized teeth were well developed

prokaryotes evolved from

pigments

Cambrian explosion

the sudden appearance of fossils resembling modern aniamal phyla in the Cambrian period

endosymbiotic theory

proposed that mitochondria and plastids were formerly small prokaryotes living within larger host cells

Endosymbiotic theory \=

evolution of eukaryotic cells

what provides the first evidence of predator-prey interactions

Cambrian explosion

cladogram v. phylogram

Long fuse \=

long period of time where there was only simple animals and then they became more complex

\__________________ colonized land first before \_________________

plants colonized land first before animals

extinct \=

the rule

extant \=

exception to the rule

what start the discussion of evolution

genetic diversity and environmental pressures

as the \________________ changes so DO \_____________--

as the environment changes so do pattern of evolution

T/F has pH falls so does CO2

false; as CO2 increases pH falls

factors that might have contributed to extinctions

-intense volcanism
-global warming and ocean acidification
-anoxic conditions

Adaptive radiation

the rapid evolution of diversely adapted species from a common ancestor

adapative radiation may be caused by

mass extinctions
the evolution of novel characteristics
the colonization of new regions

monotreme

egg laying mammals

\________________________ are one of the world's great showcases of adaptive radiation

the Hawaiian Islands

Hox and Pax gene familes

development genes;
duplications and mutations in these change organisms
and eventually the anatomy of the organisms

example of paedomorphosis

gills

Exaptations

structures that evolve in one context but become co-opted for a different function

convergent evolution leads to

analogous traits

paedomorphosis

(retention of juvenile characteristics), the rate of reproduction development accelerates compared with somatic development

the discipline of systematics

classifies organisms and determines their evolutionary relatioships

Cladograms

1. not all stems have traits
2. stems can be the absence of a trait
3. stems can be on there more than once

\______________ and \________________ are constantly changing due to phylogentic genomic sequencing

Taxonomy and phylogenies

binomial

two-part scienfitic name of a species

taxonomic groups from broad to narrow

1. domain
2. kingdom
3. phylum
4. class
5. order
6. family
7. genus
8. species

taxon

taxonomic unit at any level of heirarchy

sister taxa

groups that share an immediate common ancestor

Polytomy

a branch from which more than two groups emerge

the longer a stem

the longer the chronological time period

Nodes

represent last common ancestors and often times natural events that led to speciation as well

homology

similarity due to shared ancestry

analogy

similarity due to convergent evolution

homoplasies

analogous strutctures or molecular sequences that evolved independetly

phylogeny

the evoltuionary history of a group of organisms as depticted in the form of branching diagram

clade

a group of speics that includes an ancestral species and all its descendants (the same as a node)

monophyletic

consists of the ancestors species and all its descendent

paraphyletic

consists of an ancestral species and some, but not all, of the descendants