unit B test Flashcards
what are the 4 levels of hierarchy
ecosystems- community of living organisms and the non living compents of their enviornement
community-interacting group of populations of different species within a given area example predato prey relations
population- group of indivuals of the same species living at the same place at the same time
individuals- single organisms within a ecosystem can study how abiotic factors affect the ecosystem
what is intraspecfic comp
same animal comp
what is interspecfic comp
against diff species
faqctors affecting terssestrial ecosystems
- soil- seen as a series of layers quainty of each layer affects ecosystem productivity (topsoil- upperlayer partially decmposed leaves and grass) (topsoil- under litter rocks and decaying plant and animal matter) (subsoil- more rocks with only small amounts of organic matter) (bedrock=- compsoed of rocks)
- avaiable water
- temperature
- sunlight varys between and within ecosystems
4 factors affect aqautic ecosystems
- Chemical enviornment: amount of disslved substance and oxygen
- Temp and sunlight: affected by depth of water and seasons
- water pressure : water is 800 times denser then air
- seasonal variations
-b wnter ice acvts as isulators enviornement underneath remains stable
- spring oxygen returns intp water
- summer upper level warms lower level cools
fall- water goes from warm to cool rotating oxygen in the bottom
abitoic limmiting factors
ambient temp
percipitation/humidity
length or growing seasons
amount of sunlight,
availibility of water
availibilty of nutrients
amount of oxyegn
- these factors determine size and distributions of populations
biotic limmiting factors
compettion for resources
predation
parasites
what is a habitat
area of place in biome with specific sets of charecterics
what is a range
geographical area where a speific species may be found
what is a niche
role a species play in its community
what are the 3 groups of taxonomony in our world
Archaea: unicellular, live in dangerous enviornments, reproduce asexually,
Bacteria: unicelluar, lack membrane bound nucleaus reproduce asexually
eukraya: unicellar-multicelluar (plants and animals) sexual reproductivioty membrane bound nulcueas
what is the hierarchy
domain
kingdom
phylum
class
order
family
genus
species
what is genetic variations
naturally occoring genetic differences amoung indivuals of the same species premitting flexibility and survival of a population occors between and within species
what is intraspecific variation
occors as a result of sexual reproduction
variations giving a indiviual a better chance of survival
helps INVIDiDUAL
what are adaptations
inherited traits increasing organisms chance of surivial
structural- physical adpatations helping them survive or reproduce ex fur
physiological: helps organism with biological process ex callusus on hands
behavioral- action that helps organism survive ex: mating dance
*indivuals DO NOT adapat only way to adapt is if traits are present within a population
what are genetic mutations
variations exists because the genses in DNA can mutate, mutations are changes in intstructions from a gene
what is selective advantage and disadvantage
mutation is beneifical organism will likely survive and pass on traits
disadva- mutation is harmful organism will not adapt and will die does not pass on trait
what is natural selection
variation carrying some sort of advantage are more likely to be passed onto the offspring
these changes are driven by enviornmental change
acts on indiviuals
what does hypothesis vs theory mean
theory- explains why
hypotheiss provides an answer
what does lamarks theory reveal
discovered line of descent
belived very simple species were contiually sponitously created and then became more complex
belived that charecterics organisms aqquired during their life would be passed onto offspring “inheritence of aqquired characterics”
for example if you had strong muscles your baby would be strong
what is darwins theory
discovered indivudals with physical or behavioral advantage are more likely to survive and reproduce
competion for resources leads to survial of the fittest unfit indivuals die
what are the three observations from the theory of evolution by natural selection
1- indiviuals within any species exhibt many inherited variations
2- every generation produces for more offspring then can survive to reproduce
3- populations of species tend to remain stable in size
what are the three inferences from the theory of evolution by natural selection
1- indivduals of the same species are in constant struggle for survial
2- indiviuals with more favorable variations are more likely to survive and pass on these variations- NOT RANDOM this natural selection
3- since indivuals with more favourable variations contribute porportionally more off spring will inherit their favorable variations causing this variation to become more common (this is evolution)
what is evolution
acts on populationd
favourable traits become more common causing population to become genetically different
observed as signifigant changes in gene/ \DNA
based on pressures from environement
become so gentically diff they can no longer interbreed
fossil record
sequence fossils appear matches the sequence in which they would be expected to evolve shows gradual progression of organisms from on form to another
transition fossils and ways to date fossils
fossils that help fill in the gaps in fossil record
- radiometric dating- used to determine age of fossils
- radiocarbon dating
relative: determine sequential order of a species
index fossils: used to define and indeify diff geological periods
patterns of distrubution
geographically isolated species tend to demonstarte unique variations
closley related populations in similar geographical areas demonstarates contious variaritations
this creates a gradual divergence from a common ansector
what are homologus structures
similar in orgin therefore common ansectors but have different functions
analogus features
similar in apperance and perform similar function but don’t have same ansectors
usally occors from a common enviornment
vestigal features
structures that have no useful function
embryology
most important evidence of evolution
tiny changes in protein signally during devolpoment reults in large scale change in anatomy
physiological evidence
certain chemicals and function of these chemical are similar if not the same
molecular genetics
similarity in DNA sequences can be used to determine similarites
greater the difference less closley related organisms are dna analysis supports the idea of a shared common
artifical selection
humans slecting and breedding organisms with specific traits
what is gradualism
many biologists belive graudal change occors steadily in a linear manner, big changes result from many small changes
what is punctuated equilbrum
long periods of equilburium interupted by rapid periods of speciciation
fossil record supports this
species change the most wheny they first diverge from parent species then change very little
what is specication
formation of 2 new species from natural selection
driven by changes in environement such as formation of geographical barries
this only occors when variation causes the organism to have a better chance of survial do they become more common in population
geographic isolation leads to reproductive isolation
what are the 2 pathways for generating new species
- transformation- one species gradually changes into another by which is it replaced
- divergence- one or more species arise from a parent species that countiues to exist
3 ways populations are seperated
- Geographical isolation- mountains
- biological barrier- different mating calls
- reproductive isolation- genetic varitation allows inidviauls to begin exploting different resources
benthic zone of lake
bottom of lake
occupied by organisms adapted to low oxygen levels
littoral zone
shallow, lots of light
rooted and floating plants flourish
limnetic zone
well lit open surface occupided by phytoplankton and other producers that support the ecosystems
profundal zone
deep water with little light or oxygen (photosynthesis not possible
occupied by bottom dwellers and fish adapted to cool dark waters
