Karteikarten
Unit 4 Definitions
Karten in diesem Stapel (80)
- 1CommunityAll the populations of different species interacting together in a habitat at a given time
- 2HabitatThe conditions in which an organism lives, which is composed of both biotic and abiotic factors
- 3EnvironmentA well defined area in which an organism lives e.g. hedgerow or pond, oakwood or rocky shore
- 4PopulationThe members of one species living in one habitat at a given time
- 5NicheWhere an organism lives in a habitat and its role in the habitat
- 6EcosystemSelf contained ecological unit of community of living organisms in conjunction with the non-living components of their environment
(community + environment) - 7Random SamplingUsed to avoid bias in collecting data to ensure that the data obtained is valid
- 8AbundanceCounting the number of individuals of a species in a given space
- 9Systematic samplingSamples are taken at regular intervals within a set sample area
- 10Percentage coverAn estimate of the area within a quadrat that a particular plant species covers
- 11Mark-release-recaptureKnown number of animals caught, marked and released. Some time later given number of individuals are collected and randomly and mark recorded.
- 12FrequecyTh likelihood of a particular species occuring in a quadrat
- 13Mark-recapture-release method relies on what assumptions?1 - Marked individuals distribute themselves evenly
2 - Population has a definitive boundary
3 - Mark is not toxic
4 - Mark is not lost
5 - Few births or deaths - 14Mark-recapture-release equationno of organisms in sample 1
X
no of organisms in sample 2
--------------------------------------------
no of marked organisms recaptured - 15Factors that affect population sizeAbiotic and biotic factors
- 16Definition of abiotic factorsNon-living part of the environment
- 17Examples of abiotic factorsLight, temp, wind, water availability, humidity, salinity (salt), water movement, O2 concentration, soil, pH
- 18Definition of biotic factorsThe effect of living organisms and how they interact
(tend to have greater impact in later stages of succession) - 19Examples of biotic factorsSymbiosis, mutualism, parasitism, disease
- 20SymbiosisIntimate relationship between members of 2 species, the survival of a species relies on the success of another species
e.g. bee pollinating plants - 21MutualismA type of symbiosis between a pair of species that is mutually beneficial
e.g. Lichen - algae + fungus - 22ParasitismA type of symbiosis where the host gives and the parasite takes
e.g. ivy growing on a tree - 23DiseaseCaused by pathogens
- 24Interspecific CompetitionCompetition between organisms of different species
- 25Intraspecific CompetitionCompetitions between organisms of the same species
- 26PhosphorylationThe process of adding a phosphate group (ADP+ Pi = ATP)
- 27Light Dependent ReactionStage of photosynthesis in which light energy is required to produce ATP and reduced NADP
- 28OxidationLoss of electrons, combining oxygen with a substance
- 29ReductionGain of electrons, loss of oxygen from a substance
- 30Electron Carrier MoleculesA chain of carrier molecules along which electron pass releasing energy in the form of ATP
- 31Photolysis of WaterLight energy splits water molecule, yielding electron, hydrogen ions and oxygen
(light-dependent reaction) - 32Calvin CycleA biochemical pathway (part of the light-independent reaction) where CO2 is reduced to form carbohydrate
CO2 + RuBP = GP =TP = Glucose or RuBP - 33Limiting FactorA variable that limits the rate of a chemical reaction
- 34GlycolysisFirst part of cellular respiration in which glucose is broken down (in the cytoplasm) to 2 molecules of Pyruvate
- 35Link ReactionProcess linking glycolysis to the Krebs cycle (in the matrix of the mitochondria), where the 2 molecules of pyruvate are converted into CO2 and Acetylcoenzyme A
- 36Krebs CycleIntroducing acetylcoenzyme A into a cycle of oxidation-reduction reactions (in the matrix of the mitochondria ) that yield some ATP and large number of electrons
- 37Electron Chain TransportUse of electron from Krebs cycle to synthesis ATP via a series of oxidation-reduction reactions
- 38Anaerobic RespirationReleasing energy from glucose without oxygen (produces lactate = lactic acid)
- 39Trophic LevelsEach stage in a food chain
- 40ConsumerAn organism that obtains its energy by feeding on other organisms
- 41Gross productionTotal quantity of energy that plants in a community convert into organic matter
- 42Net ProductionGross production - respiratory losses
- 43Energy Transfer(Energy available after the transfer/energy available before the transfer) x 100
- 44Pyramid of NumberA pyramid drawn with bar lengths proportional to the number of organisms present
- 45Pyramid of BiomassA pyramid drawn with bars proportional to the mass of the plants/animals
- 46Pyramid of EnergyA pyramid drawn with bars proportional to the energy stored in organisms
- 47Biological ControlControling pests by introducing pedators
- 48Chemical ControlControlling pests by using various chemicals
- 49Integrated Pest Control SystemControlling pests by using both biological and chemical controls
- 50Selective BreedingBreeding of organism by human selection of parents for certain characteristics
- 51Saprobiotic Micro-organismsAn organisms that gets its food from the dead or decaying remains of other organisms
- 52Greenhouse GasesGases such as methane and CO2 which trap more heat energy raising the Earth temp
- 53AmmonificationProduction of ammonia from urea and proteins
- 54NitrificationConverting ammonia into nitrites then nitrates
- 55Nitrogen fixationConversion of nitrogen gas into nitrogen-containing compounds
- 56DenitrificationConversion of soil nitrates into nitrogen gas
- 57LeachingProcess by which nutrients are washed from the soil into watercourses
- 58EutrophicationConsequences of an increase in nutrients in watercourses that leads to a decrease in biodiversity
- 59SuccessionThe changes in an ecosystem, over time, of the species that occupy it
- 60Pioneer SpeciesA species that can colonise bare rock of ground. They are the first plant that colonise the bare ground
- 61Climax CommunityThe stable, final community that exists in balanced equilibrium
- 62ConservationManagement of the Earth's natural resources in such a way that maximum use can be made of them in the future
- 63GenotypeThe genetic composition of an organism
- 64PhenotypeThe (visible) characteristic of an organism, often resulting from its genotype and the environment
- 65GeneA length of DNA that codes for a polypeptide
- 66AlleleOne form of a gene
- 67Homologous ChromosomesA pair of chromosomes that have the same gene loci and determine the same features
- 68DominantAn allele that is always expressed in the phenotype
- 69RecessiveAn allele that is only expressed in the phenotype if there is another identical allele
- 70HeterozygousWhen the alleles are different for a particular gene
- 71HomozygousWhen the alleles are the same for a particular gene
- 72Sex LinkageAny gene that is carried on the X or Y chromosome
(Women = XX Men = XY) - 73Co-dominanceBoth alleles are equally dominant and are both expressed in the phenotype
- 74Multiple AllelesMore than 2 possible alleles for a particular gene
- 75Gene PoolAl the alleles of all the genes of all the individuals of a population at a given time
- 76Allelic FrequencyThe number of times that allele occurs within a gene pool
- 77Stabilising SelectionSelection that favours average individuals
- 78Directional SelectionSelection that favours individuals at one extreme
- 79SpeciationThe evolution of new species from existing species
- 80Geographical IsolationWhen a physical barrier prevent 2 populations from breeding with one another