Exam 1 Flashcards
Properties of life
cellular organization, metabolism, responsiveness, growth, homeostasis, reproduction, evolution, heredity
Property of life that only living things have
heredity
hierarchy of life
atom, macromolecules, organelles, cells, tissues, organs, organ systems, organism, population, species, community, ecosystem, biosphere
Observation
usually in a lab, to carefully watch and think
direct observation
uses senses
indirect observation
uses tools
hypothesis
more than a question, testable/falsified and a prediction
theory
organized set of facts that are accepted for the time being
Biological Qs- proximate
how qs, proximy (close in time), immediate cause and effect
Biological Qs- ontogenetic
growth qs, a sequence or delayed effect (not immediate)
Biological Qs- phylogenetic
heredity/ancestry qs, closely related ancestral species
Biological Qs- functional/ultimate
why qs, survival and reproduction (adaptations)
genes
sequence of DNA used to make an RNA copy, might be used to make a protein
alleles
alternative versions of the same gene
genome
sequence of all DNA in cells
genotype
sequence of DNA used to construct an organism
genetics
transcription and translation
genomics
comparison of DNA (between individuals or species)
autosomes
numbered chromosomes, minor role in sex determination
sex chromosomes
lettered chromosomes, major role in sex determination
gonochoristic animals
separate sexes (male and female)
dioecious plants
separate sexes (male and female)
hermaphrodites
animals that are both male and female
monoecious
plants that are both male and female
concurrent hermaphrodites
male and female at the same time
sequential hermaphrodites
male and female at different types
asexual reproduction
unfertilized eggs begin to develop
parthenogenesis
when an unfertilized animal gamete begins to develop
apomixis
when an unfertilized plant gamete begins to develop
group selection
when whole species are selected
macroevolution
evolution of species over geologic time
microevolution
changes in gene frequencies over time
founder effect
part of population is isolated from parent population
bottleneck effect
survivors of parent population (a ton die off, few survivors)
5 observable facts of natural selection
- all organisms have great potential for reproduction
- natural populations do not continuously increase in size
- natural resources are limited
- all organisms show random variation
- some variation is inherited
3 logical consequences of natural selection
- struggle for existence (competition to avoid starvation, dehydration, being eaten, diseased, or unmated)
- survival is non-random (survival of the fittest)
- over time isolated populations change and become new species
directional selection
favors one extreme, produces adaptations
diversifying selection
favors both extremes, creates speciation
stabilizing selection
disfavors both extremes, conserves DNA sequences, background selection (occurs all the time)
frequency dependent selection
rare genes come to have a selective advantage
kin selection
lowers chances of personal survival but increases chances of a relatives survival and reproduction
sexual selection
selection of traits that increase your reproduction but decrease your survival
ultimate target of natural selection
genes/DNA
immediate target of natural selection
individuals
homology
traits that are similar because they share a common ancestor
convergence
traits that are similar but do not share a common ancestor
feral species
domesticated animals return to the wild and to their natural form
vestigial traits
all species have, ancient and now useless traits
atavisms
few organisms have, mutations that cause the reappearance of an ancient trait
Hardy-Weinberg hypothesis
if evolutionary forces aren’t working, the gene won’t evolve (will be in HW equilibrium)
Hardy-Weinberg evolutionary forces
- diploid sexually reproducing organism
- large population size
- no mutation
- no gene flow
- no natural selection
positive assortative mating
non random mating, mating with similar (like) individuals
negative assortative mating
non random mating, mating with dissimilar (unlike/opposite) individuals
identifying species: morphological species concept
identifies based on similar structure and function only, asexually reproducing species
identifying species: biological species concept
sexually reproducing species, identifies based on:
1. A gene pool
2. fertile offspring
3. reproductive barriers (prezygotic or postzygotic)
postzygotic barrier: hybrid inviability
embryos fail (miscarriage)
postzygotic barrier: hybrid sterility
adult offspring is sterile/can’t reproduce
postzygotic barrier: hybrid breakdown
offspring die young
allopatric speciation
populations become geographically isolated, makes new species
sympatric speciation
new speices arise in the same range (not separated)
divergent tectonic plates
makes rifts, fill with water
convergent tectonic plates
makes mountains
continental islands
break/form from continents, has the same species as the continent
oceanic islands
come from volcanoes, ocean acts as a species filter
Main source of evidence for evolution
living organisms, NOT FOSSILS
background extinction
occurring all the time at a very low level, caused by changes in temperature and moisture
mass extinction
more than 50% of all species go extinct, happens suddenly, caused by intense volcanism or impacts by asteroids
binomial method of naming
First Name Capitalized Generic Name
Second Name Lower Case Specific Name
Taxonomic hierarchy
Domain
Kingdom
Phylum
Class
Order
Family
Genus
Species
domain
DNA, RNA, organelles
kingdom
overall lifestyle difference (autotrophs, heterotrophs) (uni/multicellular)
phylum
body plan
class
layout of organ systems
order
subjective rules, based on taxonomist expertise
family
sharing most characters (look very similar)
genus
may interbreed within same genera, will have non fertile offspring
species
always make fertile offspring
subspecies
geographically isolated, but can still interbreed
simple varieties
minor heritable differences (coat color, horn length)
acquired varieties
minor acquired differences (diet, temperature)
systematics
no rules- rely on expertise, logic, and intuition to determine species relationships
cladistics
well defined procedures for determining species relathionships
symplesiomorphy
shared ancestral character
synapomorphy
derived trait shared by ancestral and descendant speices
autapomorphy
unique derived trait in one descendant species
stem groups
extinct ancestors
crown groups
extant (alive) ancestors
cladogram
time is not represented, derived characters have explained divergence
phylogram
shows time based on branch lengths
root of a tree
oldest group, outgroup, ancestral group
node of a tree
branch point, shows divergence
species tree
follows lineage of species
genetic tree
follows where genes mutate
adaptive radiation
new species quickly come about, usually after mass extinction
sister taxa
2 species that come from a recent common ancestor
polytomy
one species gives rise to more than two new species
clade
ancestry or lineage of 1 species (1 line on a tree)
Monoplyletic group
shows correct relationship among species in a cladogram, all species share a common ancestor
paraphyletic group
mistake, show incomplete group of species in a cladogram, leaves out a species that should be included
polyphyletic group
shows species with different common ancestors in a cladogram, mistake due to convergence
anagenesis
a change in 1 lineage only (doesn’t diverge)
cladogenesis
splitting of a lineage into 2 (does diverge)
6 kingdoms of life
- eubacteria
- archea
- protists
- fungi
- plants
- animals
Prokaryotes
Smaller cells
DNA: circular, no introns, operons
No organelles
Flagellin rotates
Cell walls
Unicellular/colonial
Divide by fission
Eukaryotes
Larger cells
DNA: Linear, introns, no operons
Has organelles
Tubulin waves
Cell walls (plants + fungi) or cytoskeletons (animals)
Multicellular
Divide by mitosis and meiosis
algae
photosynthetic protists
protozoan
non photosynthetic
mixotrophs
are a combination of photosynthetic and non photosynthetic, can eat and make their own food
Cyanobacterium is where we get …
chloroplasts (endosymbiosis)
red algae were engulfed in endosymbiosis to create …
chromalveolates
ancestor of all algae and plants
cyanobacterium
green algae were engulfed in endosymbiosis to create …
euglenids
symbiotic theory
-endosymbiosis, not true multicellularity
-one cell lives inside another
coenocytic theory
-some fungi and slime molds
-nucleus of 1 cell replicates its nucleus and forms a membrane around each nucleus
aggregative theory
-some fungi and slime molds
-non-sister cells come together to form a multicellular organism, usually only an emergency response
clonal theory
-plants and animals
-sister cells (clonal cells) come together to form an organism
Facultative multicellular organisms
colony of cells that are not dependent on one another
Obligate multicellular organisms
eukaryotes only, are cells that depend on one another
criteria for multicellularity
- Adherence (connect together)
- Communication (respond to chemical signals)
- Dependent on each other
- Differentiation (switching genes on or off)
Ectoplasm
just underneath the cell membrane, thick gel that provides support
endoplasm
thin, watery, cytoplasm
Excavata unique characteristics
Cytostome feeding groove
Atypical, lost, or reduced mitochondria
Euglenids
excavata that are mixotrophs, have atypical mitochondria
Algae alternation of generations
Biphasic life cycle, start with sporophytes (2n) which become gametophytes (n)
sporophyte
diploid, go through meiosis to produce spores which germinate into gametophytes
gametophytes
haploid, go through mitosis, will produce sporophytes
ancestor of all land plants
green algae
green algae
colonial, unicellular, or obligate (true multicellular)
red algae
mostly colonial species, few unicellular
Red algae unique characteristic
double cell walls
Brown algae
all multicellular
yellow/gold algae
unicellular
Diatoms
marine yellow algae, most abundant marine photosynthesizer (1/2 of ocean production, 20-30% of O2)
Dinoflagellates
-Yellow/gold algae
-Zooxanthellae (form symbiotic relationship w/ marine life)
-Bioluminescence
Ciliates unique characteristics
heterokaryotic (have micro and macro nuclei)
Plasmodium
Responsible for malaria through sporozoites and merozoites
sporozoite
injected by mosquito bites into blood stream, enters liver cells
merozoite
exits liver cells, enters RBCs and feeds on hemoglobin (where symptoms appear), goes through mitosis and meiosis
radiolarian
- spiky internal silica skeletons
- fixed axopodia (rays of amoeba)
foraminifera
- smooth external calcium carbonate tests
- flowing and merging reticulopodia (branches of amoeba)
heliozoans
freshwater amoebas, make external silica test
gymnamoeba
naked amoeba (no test)
cercozoan
amoebas with flagella
pseudopodia
slowest amoeba, extend cell membrane for movement/feeding
lobopodia feeding
thick extensions of amoeba, mass movement of part of cell
filopodia feeding
thin extensions of amoeba
reticulopodia feeding
branches of amoeba
axopodia feeding
fixed, permanent rays of amoeba
Unicellular slime molds are haploid or diploid
haploid
multicellular slime molds are haploid or diploid
diploid
nucleariids
amoebas, ancestors of fungi
first single celled fungi
chytrids
choanoflagellates
can live in multicellular colonies, ancestor of all animals