Biodiversity and ecosystems Flashcards
what is biodiversity?
the variety that exits in life forms on this planet
what are the three different levels of biodiversity and explain them
genetics- molecular diversity within a gene population
species- population diversity referring to the variety of different species in a habitat
ecosystems- diversity which refers to the different ecosystems
why is biodiversity so important
- oxygen, food and fresh water
- provides resources and raw materials
- breakdown of waste materials
the hight the biodiversity of an …
ecosystem the more stable it is. population with reduced genetic diversity face increased extinction level
what is endemic
it refers to a plant or animal species that are only found naturally in a region or country
what is species
refers to a group of organisms that have much of their DNA sequences and genetic makeup.
what characteristics are species grouped in
Physiological, morphology and behavioural characteristics
what is a phenotypes
the appearance of an organism and is a direct expression of its genotypes
what is a genotypes
the genes the individual passes and their physical characteristics
what is genetic diversity
the verity of genes and forms of the genes tjay occur within a particular species
what is natural selection
the process through which populations of living organisms adapt and change
what is genetic drift
population of organisms may experience variation in the different genotypes due to the loss of genes as individuals die from the population
what is natural selection
traits of a species that change to better suit the environment
what is genetic drift
population or organism may experience variation in the frequency of different genotypes due to the last genes are lost from the population
what is the bottle neck effect
major changes in the gene pool caused by drastic reduction in population size
what can cause the bottle neck effect
droughts, fires, floods, deforestation , hunting, diseases
what is competition
- it is a community interaction
- organism complete for the same food
- most intense between same species or species that have similar requirements
what is predation
- a community interaction
- one organism feed on another live organism
- this could be feeding on plants or other animals
what is symbiosis
distinct relationships between two different species divided into three categories
- mutualism
- commensalism
- parasitism
what is mutalism
beneficial relationship between two different species
what is commensalism
one species benefits but the other us unharmed
what is parasitism
parasits that lives on/in the host and obtains food and shelter. the host is harmed and will generally die
what is ecosystem
Includes all living organisms (biotic) and the physical environment (abiotic) functioning together as a unit
heterotrophs in a community is called
consumers
- herbivores (primary consumers)
- carnivores (high order consumers)
what is a trophic structure
the community of living organisms within an ecosystem is trophic structure. this is apattern of feeding relationships in the ecosystems.
the hight the trophic level the…
the less the individuals are in the population
what are primary consumers
feeds on produces, secondary consumers feed on primary consumers and so on
what are decomposers
- obtain nutrition from dead materials at all trophic levels
- they recycle so they return the nutrients back into the ecosystem
what is the structure of a population
organisms-> populations -> community -> ecosystems
what is biotic
living factors part of an ecosystem (plants, animals and bacteria)
what is abiotic
non living factors of ecosystem (air, material, temp)
what is a food chain
where each individual feeds on the organisms below it in the chain. in a food chain energy is transferred from organism to organism in the direction of the arrow
what are producers as consumers
make their own food
what are primary consumers
eats producers
what are secondary concumers
eat primary consumers
what is tertiary consumers
eats secondary consumers
why is biological classification important
it allow scientists to identify groups and properly name organisms using standard system based on similarities
how do we classify things
- structural
- biochemical
-cytological - embryological
- behavioural (not very reliable)
- fossils
what is the binomial naming system
first is genus (first letter capitalized )
second is species
written in italics
what is hierarachal classification
- based on shared characteristics and molecular similarities
- eukarya, archaea, bacteria
5 kingdoms of classification
- bacteria
- protist
- fungus
- animal
- plant
organism classification
- number of cells (unicellular VS multicellular)
- type of cells
basis of classification
- physical features
- reproductive strategies
- molecular features
what are physical features
- are an expression of the genotype and the environment, organism with similar features are closer related to
eg: animals: exoskeleton, feather, organs
what are reproductive strategies
- method of reproduction by sexual means, fusion or fertilisation, other asexul means not invloving gametes
how are mammals separated by reproductive strategies
- placentals (eg: humans)
- marsupials (eg: kangaroos)
- monotremes (eg: echidna)
what is molecular sequencing
- DNA is made of (A,C,G,T)
- cytochrome C is a protien needed for aerobic respiration for all living organisms
what does A, C, G, T stand for
- adenine
- cytosine
- guanine
-thymine
what is a population
ecosystems consist of a large number of different species. a population is a group of the same speies within the same ecosystem at the same time
what is a community
population of different species interact with each other within the same ecosystem making a community
what is a niche
-the way a population of organisms function in an ecosystem is an ecological niche]its discribed in therm of the population habitat and the roles the organisms in the population
What is Gause’s principle
two or more resource- limited species having identical patterns or resources use cannot coexist in a stable environment. one species will be better adapted and will outcomplete the other
what is a fundamental niche
no compatiton
what is a realised niche
increased compatiton
ecosystem with higher biodiversity are ….
more likely to resist change and remain intact. this is a stable ecosystem if maintained for long periods of time
what is low diversity
results in less resilience so they are know as unstable ecosystems
keystone species are..
critical to the stability of the ecosystem
