human impact on environment and p and ecosystems Flashcards
give 3 reasons for classification
allows extinct organisms to be grouped with existing orgs to explain evolutionary relationships
-makes communication easier.
-allows scientists to compare rates of extinction in large groups of organisms e.g families.
what are the 3 domains defined on?
defined on the similarities and differences in the rRNA base sequences or DNA
name the three domains
Eubacteria
archea
Eukaryota.
which of the domains describes those with unusual metabolism living in unusual environments.
archaea
give the 8 points in the 3 domain system of classification
-domain
-kingdom
-phylum
-class
-order
-family
-genus
-species
name the 5 kingdoms
-animalia
-plantae
-potoctista
-fungi
-prokaryotae.
define taxonomy
identification and naming of organisms
give 5 features of animalia
-eukaryotic
-no cell wall
-nervous coordination
-heterotrophic
-multicellular
give 4 features of plantae
-eukaryotic
-multicellular
-cellulose cell wall
-autotrophic
give 4 features of fungi
-eukaryotic
-some uni/multicellular
-heterotrophic( saprotrophic and parastitic)
-chitin cell wall.
give 4 features of protoctista
-eukaryotic
-single celled, colonial or multicellular
-no tissue differentiation
-can be heterotrophic or autotrophic.
give 5 features of prokaryotae
-only bacteria
-unicellular
-no nucleus/membrane bound organelles.
- cell wall made of murein
-heterotrophic, saprophytic or parastitic
what is species richness vs species evenness
richness= no of species
evenness= no of individuals of each species.
the more similar two organisms are the more recently they are said to have…….
diverged
what does a photogenic tree demonstrate
how closely related species are and how recently they have diverged from a common ancestor
describe divergent evolution (d for developmental orgin)
homologous structures that have a common developmental origin but have different functions e.g human arm and bat wing.
describe convergent evolution
development of analogous similar structures with different developmental orgins not evidence for a common ancestor e.g wings in birds and insects
describe polymorphic loci
gene pools have more than one allele for a given gene-polymorphic genes so the locus (location) on a chromosome is also polymorphic. the more polymorphic loci within a genome of species, the more biodiversity.
describe 4 ways to analyse biodiversity at a molecular level
-DNA profiling- using fingerprinting with electrophoresis gel.
-protein analysis- comparison of sequence of amino acids in proteins done by chromatography-reduced errors by convergent evolution.-DNA hybridisation- DNA traken from different species is cut and mixed, complementary fragments hybridise- more bonds formed=closer related.
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name the three adaptation types
-anatomical
-physiological
-behavioural
state the equation for capture mark recapture
n1xn2/n3 n1-capture n2-2nd capture n3-no of recaptures marked
deascirbe difference between belt and line transect
belt- uses quadrat to estimate %freq.
line-measuring at intervals not using quadrat
give the simpsons index
1-(⨊n(n-1)/N(N-1))
give the definition for selection pressure
an environmental factor that can alter the frequency of alleles in a population
is a species with controlled population by competition in a stable habitat equilibrium or fugitive species with sigmoidal growth curve.
equilibium.
what happens in the lag phase of sigmoidal growth
period of preparation and adaptation and time for sexual maturity.
what happens in exponential growth phase
more growth- more available for reproduction- growth may slow due to environmental resistance
describe ammonification nitrogen cycle
proteins broken down into amino acids by ammonifying bacteria.
describe nitrification
ammonium ions oxidised to nitrites (N02-) by nitrosomonas, nitrites oxides to nitrates by nitrobacter (N03-) N2 atoms fro nitrates joins with an organic molecule to make protein used for plant growth.
describe nitrogen fixation
enzyme in bacteria combined N2 to H to form ammonia can form bacteria protein.
aztobacter is free living in soil.
-rhizobium- legumes in root nodules.
how rhizobium attracts plants
-chemical secreted by roots attracts, chemicals secreted by rhizobium attarcts roots-chemotaxis. bacteria multiply in cortex cells, they use an enzyme to fix nitrogen-is inhibityed by high 02 levels so legume has legheamoglobin creating anaerobic conditions.
describe the function of denitrififying bacteria/pseudomonas
convert nitrates of nitrogen gas
-live in anaerobic conditions.
give 3 ways of improving the nitrogen circulation
-ploughing/drainage of fields more nitrogen fixation
-harber process-nitrogen to fertiliser
-animal waste and manure
-planting legumes.
what is the gross primary production
total amount fixed for photosynthesis
what is net primary production
how much energy is available for primary consumers.
give the equation for working out net primary productivity
NPP=GPP-R r=respiratory loss
give some examples of agricultural exploitation
-remova; of hedgrows
-monoculture
-mineral depletion in soils
-fertilisers and eutrophication.
-overgrzing.
give 3 forest managemnet tyechniques that provide timber in a sustainable way
-coppicing
-selective cutting
-lomgh rotation time
-preserving natural woodland.
-give one of the biggest causes of overfishing
small net mesh sizes- young are caught befre sexual maturity.
give some methods of regulation
-mesh size restriction
-fishing quotas
-reducing fleet size.
-controlling days sp[ent at size.
-protected zones and consumer choice.
give two advantages to fish farming
-densely stocked-disease
-antibiotics used
-pesticides used
-pollution could cause eutrophication e.g faeces.
-escaped fish outcompete.
-can degrade the ernvironment.
give a way of measure environmental impact of a project/process
environmental impact assesments.
