Biology QCE

biodiversity

the variety of life in the world or in a particular habitat or ecosystem, including diversity within species, between species, and of ecosystems

ecosystem

a self-sustaining

unit consisting of the

interactions between

the species in a

community and the

environment

species

the lowest taxon in

Linnaean classification;

it is always italicised

and combined with

genus, e.g. catus in

Felis catus

biotic factors

the living components

of an ecosystem,

including animals,

plants and bacteria

abiotic factors

non living components of an ecosystem. e.g weather, pH of soil, gases. differ of spacial scale.

photosynthesis

process of using light energy to convert carbon dioxide and water into glucose and oxygen. energy transformed through photosynthesis then is transferred to organisms through food webs

food web

interconnecting food chains shows how different organisms feed off each other thereby transferring energy.

species richness

number of species in an ecosystem

relative species abundance

number of individual species present for each species in an ecosystem

Percentage cover

percentage of quadrat in which a species appears

Percentage frequency

the percentage of quadrats a species appears in

Simpsons Diveristy Index

combination ratio of individuals in an ecosystem. Quantative measure of biodiversity

Three types of biodiversity

genetic diversity: range of genes within a species

species diversity: range of different species in an ecosystem

ecosystem diversity: number of habitats in ecosystem

why is species diversity important within an ecosystem

each species has a different role to maintain a balance between growth and predation, nutrition and mortality. Ecosystems with hgiher diveristy adapt better than ecosystems with less.

explain difference between species richness and relative species abundance

richness is the number of species present in an ecosystem. abundance however is the number of individuals present for each species

spatial scale

how much area a studied ecosystem covers. Uses three levels

Macro: large area, typically whole continent

Meso: medium sized area, single location e.g lake or desert

Micro: small area, single biome e.g rainforest

What terms are compared across spacial scales

Predation: species kills another to eat

Competition: species interaction where two or more individuals compete for the same resources in the same area

Producer and Consumer

Producer: converts energy to sugar, e.g plant animals eat

Consumer: first and second level, eats other organisms for nutrition and energy

Temporal Scale

Time period an ecosystem is studied. short term, e.g 24hrs or long term e.g years.

how can species diversity differ in the same place but at a different time

species index can change depending on the time with nocturnal and diurnal organisms. Hibernation or migration during some parts of the year.

How can abiotic factors differ between spacial scales

temperature over different latitudes or salinity in different oceans

Limiting factor

aspect of environment that restricts an organisms ability to live there. restricted by not enough resources for organism

Three biotic and abioitic factors that can limit species population

Biotic: preadation, competition, lack of appropriate food sources, poor habitat access

ABiotic: temp, rainfall, soil salinitym light levelsm poor camouflage

Two limiting factors for human population in QLD

need for living, low supply of adequate housing, land oning for farms and parks, flood risk

Limiting factors for shark populations

human culling, inadequate fish stocks to service both human and shark populations

Describe common characteristics of a healthy ecosystem

many different species. balanced triangle of trophic stages, (producers, consumers and decomposers) no over abundant species. stable community over long periods of time

Explain how environmental factors limit the distribution and abundance of species in an ecosystem.

The distribution of species is limited by their ability to access adequate food sources and habitats. They will be limited to areas where these factors are beneficial for their survival. The abundance of species is limited by the abundance of food, water and shelter in the areas with beneficial factors.

how can temporal scales affect the reported diveristy of an area

Reported diversity relies on sampling, which must be done at a specific time. Ecosystems change over the course of a day, a year and longer timescales, making it easy for sampling at different times to return different diversity measures.

Explain how limiting factors can be used to focus rehabilitation efforts.

Limiting factors restrict an organism’s ability to live in an area, so by identifying and mitigating abiotic and biotic factors that are working against the success of a particular species in an area, the population can be rehabilitated.

interspecies and intraspecies competition

Interspecies: different species

Instraspecies: same species

Taxonomy

a system of classification. grouped into categories based on common features. Hierarchical system.

two benefits of classifying organisms

Classifying organisms is beneficial in simplifying and condensing the vast diversity of life on Earth and visualising the relationships between groups of organisms.

explain limitations of classification

Classification choices are not universal, which causes contention among the scientific community about the ‘right’ way and major similarities and differences are emphasised, while minor similarities and differences are ignored.

Linnaean Classification (DKPCOFGS)

Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species

Domain: 3, animal vegetable and mineral

What is included in domain Eukarya

Eukaryotes; complex type of cel with nucleous and membrane bound organelle

Animalia, Plantae, Prostista, Fungi

What are Domain Archaea and Bacteria

Prokaryotes: simple type of cell lacks nucleous and membrane bound organelles.

Different way in which DNA is stored and how proteins are synthesised, therefore in seperate domain.

Members of archaea live in extreme environments (High salt/temp)

four kingdoms in Domain Eukarya

Animalia;Contains all the animals

Plantae: Plants, have cell walls

Prostista: aqueous

Fungi: Yeast, mushrooms and moulds, have cell walls

What is Binomial Nomenclature

a naming system in which each individual is given a two-part name, such as genus and species or first name and surname

what is r/K selection

a form of mathematical classification based on the number of offspring a species produces and the level of parental involvement required to care for them

r-selected: produce large number of offspring with little parental investment. High juvenile mortality rates. e/g fish and rodents

K-selected: small number of offspring with lots of parental supervision. lower juvenile mortality rates

What are amino Acids in Molecular sequencing

simple organic compound combining to make proteins. order of amino acids can hep classify organisms

three categories of characterisitics used to classify organisms

Physiological traits, reproductive methods and molecular sequences

how is molecular sequencing used to classify organisms using ammino acides

Molecules such as proteins or DNA are sequenced and those sequences are compared. The number and nature of differences are used to rank relatedness.

Three assumptions of cladistics

1. all life evolved from a common ancestor therefore any group of organisms will share a common ancestor at some point

2. Offspring of an ancestor diverge dichotomously in a process called cladogenesis

3. organisms become increasingly different as they continue evolving from the point of cladogenesis