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90 Cards in this Set

  • Front
  • Back
Law of dominance
dominant allele masks recessive allele
law of segregation
a pair of alleles separate during gamete formation(meiosis)
independent assortment
all sets of alleles separate randomly and independently
alleles are alike : PP pp
alleles are diff : Pp
F1 generation, masks other trait in pair
F2 generation, the weaker allele, two copies must be present to express
organism's genetic makeup : PP Pp
organisms appearance Pp is purple..pp is white
test crosses
the crossing of an individual of unknown genotype w/ a homozygous recessive individual to determine unknown genotype
incomplete dominance
offspring have a phenotype between that of the parents. Neither allele is Completely dominant over the other....Ex. 1 RR: 2 Rr: 1rr
a cross in which only one characteristic is tracked....PPx pp
a condition in which both alleles for a gene are fully expressed
cross in which two characteristics are tracked...ex. both texture and color are tracked...16 punnet
gene expression
the activation or "turning on" of a gene that results in transcription and the production of mRNA (most mRNA translates into proteins)
it initializes transcription
complete genetic material contained in an individual
this protein initiates gene expression
sex chromosomes
determine the sex of the baby if there are two x's then the baby is a girl...if tyhere is one x and one y then it is a male
sex linked traits
the female carries the gene and the males lack that gene
squares are males, circles are females, shaded means they have the inherited trait
human genome project
a research effort undertaken to sequence all of our DNA and locate within it all of the functionally important sequences such as genes
earth age
earth is 4.5 billion years old and life first appeared 3.5 billion years ago
appear before autotrophs
appear before eukaryotes
radioactive dating
a method of determining the absolute age of an object by comparing the relative percentages of radioactive isotope and a stable isotope
half life
the time required for half of a sample of a radioactiveisotope to break down by radioactive decay to form a daughter isotope
carbon 14
radioactive isotope
carbon 12
stable isotope
darwins theory
four main points= overproduction, struggle to survive, genetic variation, differential reproduction
lamarcks theory
traits are inherited , the animals strive to make themselves better...giraffes had short necks but stretched to trees which gave them long n's and the offspring inherited that trait
darwins theory
the individuals with favorable traits will survive and the ones w/out them wont survive
the process of becoming adapted to an environment:an anomatical,physiological, or behavioral trait that improves the ability to live
survival of the fittest
geology-charles lyell-gradual gological changes influence plant and animal life.......selective breeding has resulted in organisms w/ little resemblence to their ancestors
artificial selection
the selective breeding of organisms by humans for specific desirable characteristics
population control
more offspring are born than can survive
the trace of remains of an organism that lived long ago, most commonly preserved insedimentary
genetic code is universal. More closely related organisms are the more smaller their DNA
anatomical structures in one species that compared to another species originated from a single anatomical strucure in a common ancestor of the two species
a structure in an organism that is reduced insize and function and that may have been complete and funtional in the organisms ancestors
an anatomical structure in one species that is similar in funtion and appearance but not in evolutionary origin to another anatomical structure in another species
the process by which unrelated species become more similar as they adapt to the same kind of environment
the process by which two or more related but repoductively isolated popilations become more and more dissimilar
hardy-weinburgs principle
the frequencies of alleles ina population does not change over generations unless outside forves act on the population
population genetics
the study of the frequency and interaction of alleles and genes in populations
gene pool
all of the genes of the reproductively active members of a population
genetic equilibrium
frequency of alleles remains the same generation to generation
genetic drift
random change in allele frequencies due to change event(migration, natural disasters)
levels of biosphere
oraganism, population, community, ecosystem, biosphere
an independent individual that posesses all characteristics of life
a group of various species that live in a specific geographical area and iterbreed
a group of various species that live in the same habitat and interact with each other
a communiity of organisms and their abiotic environment
includes all living organisms on earth
an organism that can make organic molecules from inorganic molecules; a photosynthetic or chemosynthetic autotrph that serves as the basic food source in an ecosystem
an organism that eats other organisms or organic matter instead of producing it's own nutrients of obtaining nutrients from inorganic sources
an organism that feeds by breaking down organic matter from dead organisms
Ex. bacteria and fungi
food chains
the pathway of energy transfer through various stages as a result of the feeding patterns of a series of organisms
food web
a diagram that shows the feeding relationships among organisms in an ecosystem
ecological pyramids
it takes a lot of producers to have the evergy transfered to larger animals at the top
trophic levels
an organisms relative position in a sequence of energy transfer in a food chain or food pyriamid
ex. producers, primary, secondary, tertiary consumer
any organic material that has been produced in an ecosystem
carbon cycle
the movement of carbon from the nonliving environment into living things and back
nitrogen cycle
the process in which nitrogen circulates among the air, soil, water, plants, and animals in an ecosystem
cycle through ecosystem
lost as you go through the food chain...and does not cycle through the exosystem but is supplied by the sun
factors that influence populations
limiting factors, carrying capacity expotential growth, density dependent factors, density independent factors
limiting factors
an environmental factor that prevents and organism of poulation from reaching its full potential of distibution or activity
carrying capacity
the largest poulation that an environment can support at any given time
density depedent factors
a variable affected by the number of organisms in a given area
density independent factors
a variable that affects a population regardless of the poulation density such as a climate
a realationship inwhich two diff organisms live in close association with each other
a relationship between two species in which both species benefit....bees and flowers
a relationship between two organisms in which one organisms benfits and the other is unaffects......cattle egrets and cape buffaloes
a relationship between two species in which one species, the parasite benefits from the other species the host which is harmed...lice
ecological succession
a gradual proccess of gange and replacement in a community
primary succession
succession that begins in an area that previously didnt support life
secondary succession
the process by which one community replaces another community that has been partially or totally destroyed
pioneer communities
a species that colonizes an uninhabited area and that starts an ecological cycle in which many other species become established
climax communities
a community that, after a process of ecological succession has reached a generally stable state
theyy are known by the presence of plants and animals
graph precipitation and temperature of a given area
renewable resources
trees are a renewable resource because it can be grown again
non-renewable resources
a forest is a nonrenewable resource
it can break down in the earth over time
cannot break down; will take a very long time to break down
water pollution
people dump raw sewage or trash into the water
chemical pollution
produces smog which is form human activities, burning fuel, and using chemicals in vehiclas homes and industries
cause of pollution
hole in warming
non native species
species that are introduced into a new environment