ecosystems Flashcards
classification naming
- binomial nonmenclature
- latin
- italics
- genus is capitalized (first part)
- species is lower case (second part)
- carols ligneous developed the system
classification
method for finding the identity of something
why classify
- to study the diversity of life
- organs and name organisms
dichotomous key
- divided into 2 parts
- lead to another question till its identified
methods of reproduction
sexual - egg and sperm from 2 parents
internal: sperm and egg unite inside the females body e.g. human
external: sperm and egg unite outside the body e.g. frog
hermaphrodite: male and female reproductive organs in one body e.g. tapeworm
asexual - offspring come from a single organism
domain
- eukarya
- bacteria
- archaea
kingdom
- archebacteria
- eubacteria
- protista
- plantae
- fungi
- animalia
invertebrates
- no vertebrate/backbone
- 95% of all animals
radial symmetry
- parts extend from the centre of the body
bilateral symmetry
- mirror image, left/right sides
vertebrates
- have backbones, vertebral columns 5 main groups - mammals - birds - amphibians - fish - reptiles
mammals
- give brith to live young
- nurse young with milk
- have lungs and need air to breathe
- warm blooded
birds
- have feathers, 2 wings
- lay eggs
- warm blooded
- breathe through lungs
amphibians
- live in land and water
- may undergo metamorphosis, start living under water using gills then develop lungs to live on land
- cold blooded
- webbed feet
- frog
fish
- breathe underwater using gills
- have scales and fins
- cold blooded
- lay eggs
reptiles
- lay eggs on land
- cold blooded
- live on water and land
- most hibernate
species
- morphological
- genetic similarity
- the ability to interbreed to produce fertile offspring in natural conditions
- up to 100 million species
- many are extinct
biological species concept
- groups of actually or potentially interbreeding natural populations which are reproductively isolated from other groups
limitations in species
- ring species
- clines
- hybrids/cross breeding
- collaborations between species
ring species
- situation in which 2 populations do not interbreed but are connected by a geographic ring of populations that can interbreed
clines
- forms of species that exhibit gradual phenotype or genetic differences
- as a result of different environment
- many manifest in time or space
hybrids/cross breeding
- some species interbreed/ mate with one another and produce offspring
- unless this offspring is fertile it is technically not a species
- artificial selection = cross breeding unnatural situations
collaborations between species
- combined life form has properties that are very different fro properties of its component organism
ecology
- study of the relationship between organisms and their abiotic and biotic factors
environments
terrestrial - climatic variation e.g. tundra desert
aquatic - marine/freshwater
factors affecting ecosystems
- abiotic: temperature, wind speed
- biotic: producers, consumers, predators
- physical gradients: habitats
energy flow
- all organisms require energy (heat,cheimcal,mechanical)
- for growth
- maintenance
- reproduction
autotrophs
- producers
- use the suns energy to make their own food
- photoautotrophs: use photosynthesis to fix carbon and energy and store it in food
- chemoautotrophs: use inorganic energy sources to synthesize organic compounds from carbon dioxide
heterotrophs
- consumers
- cannot manufacture its own food
- intake of nutrition is from other animals/plants
energy in ecosystems
- matter is recycled, energy isn’t
- need a constant input of new energy from the sun
- energy is lost as heat to the atmosphere
most productive ecosystem have
- high temp
- plenty of water
- high soil nutrition
symbiosis
parasitism: one species benefits at the expense of the other
mutualism: both species benefit and neither is harmed
commensalism: one species benefits and the other neither benefits or is harmed
food chain problems
- too simplistic
- no detritivores
- chains too long
ecology rules
- everything is connected
- everything must go somewhere
- there is no such thing as free lunch
productivity
- the rate at which energy is added to the bodies of a group of organisms in the form of biomass
biomass
- the amount of matter thats stored in the bodies of organisms
primary productivity
- the productivity of the primary producers of an ecosystem
gross primary productivity: the rate at which solar energy is captured in sugar molecules during photosynthesis
net primary productivity: gpp - the rate of energy loss to metabolism and maintenance - rate at which energy is stored as biomass by plants and made available to the consumers in the ecosystem
secondary productivity
the generation of biomass of heterotrophic organisms in a system
primary productivity depends on
- light intensity
- temperature
- water
- mineral supply
trophic levels
1 - producers e.g. tree
2 - herbivores e.g. cow
3 - primary carnivore e.g. wolf
4 - secondary carnivore e.g. killer whale
5 - omnivore e.g. bear
6 - detritivores/ decomposers e.g. tapeworm
energy is lost as heat from each level via respiration
producers
make their own food from simple inorganic substances
> waste: metabolic waste products are released
> reflected light: unused solar radiation is reflected off the surface of the organism
> eaten by consumers
> dead tissue: becomes food for decomposers
herbivores/ carnivores
- feed on other organisms to obtain their energy
> waste: e.g. urine
> eaten by consumers: carnivores, omnivores
> dead tissue: becomes food for decomposers
> growth and reproduction: new offspring as well as growth and weight gain
< food: consumers obtain their energy from plant tissue
decomposers
- obtain their nutrients from the breakdown of dead organic matter
> waste: metabolic waste is released
> growth and reproduction: new tissue created mostly in the form of offspring
< dead tissue of producers and consumers
energy transformations
- green plants use the suns energy to produce glucose via photosynthesis
- chemical energy stored in glucose files metabolism
photosynthesis - provides O2 and absorbs CO2
cellular respiration - organisms break down energy rich in molecules to release the energy in a useable form
pyramid of energy
- depicts the energy flow or productivity of each level
- each higher level must be smaller then the lower levels due to loss of energy via respiration
pyramid of numbers
- the number of organisms in each level
pyramid of biomass
- biomass present in each level
- biomass can be equated to energy
- dry weight in each level at a time
inverted pyramids
- a higher level may have a larger standing crop the a lower level
- can occur if lower levels have a high rate of turnover of small organisms
biodiversity
the variety of life on earth and the interdependence of all living things
why protect biodiversity
moral: right to exist, stewardship
economic: valuable resources, ecotourism, medicines
ecological: maintain ecosystem health, productivity
legal: have to by law
aesthetic: interest, curiosity
causes of biodiversity loss
- habitat loss/change: less food, shelter
- invasive/feral species: predators, compete for food
- climate change: affects breeding, food, habitat
- overexploitation: hunting etc reduces population size
- pollution
nomenclature/ taxonomic levels
domain kingdom phylum class order family genus species dumb kings play chess on folding glass stools
nitrogen cycle
- nitrogen atoms cycle between the biotic and abiotic environment
- nitrogen fixing bacteria are able to fix atmospheric nitrogen
- nitrifying bacteria convert ammonia to nitrite and nitrite to nitrate
- denitrifying bacteria return fixed nitrogen to the atmosphere
carbon cycle
- carbon atoms cycle between biotic (living) and abiotic ( non-living) environments
- CO2 is fixed in the process of photosynthesis and returned to the atmosphere in respirations
- humans have disturbed the carbon cycle through activities such as combustion and deforestation
biological diversity
genetic, species, ecosystem
genetic: gene variation in a population
- from sexual reproduction, fertilisation and crossing over
- in alleles T or t, in individuals TT,Tt,tt
ecosystem: the variety of ecosystem interaction within a community
importance of biodiversity
- regulation of climate
- soil protection
- pest control
- ecological stability
causes of extinction
- habitat destruction
- over harvesting
- displacement of introduced species
endangered
species are in danger of extinction throughout part or all of their range
threatened
species have low population sizes are likely to become endangered in the future
habitat fragmentation
- cause of biodiversity decline
- cuts continuous habitat into smaller parts
- patches grow further apart, organisms can’t move between them
lose of biodiversity makes ecosystems
- less stable
- more vulnerable to extreme events
- weakens natural cycles
human activities that disrupt ecosystems
- pollution
- introduction of non-native species
- over harvesting of fish
sustainability
higher biodiversity = more sustainable
lower biodiversity = less sustainable
preserving earths biodiversity
off site conservation
- species to be protected are removed from their natural habitats and placed in safer controlled areas
on site conservation
- protection of species within the natural habitat
keystone species
- species whose influences on ecological communities is greater then would be expected on the basis of their abundance
- more influential in ecosystem stability
diversity indices
- best ways to determine health of an ecosystem is to measure the variety of organisms living in it
relationship
predation - one organism eats another
competition - struggle between different organisms for the same limited resources
collaboration - occurs between organisms in a group against predators, involves species benefitting each other
symbiosis
disease - reduces the survival of others by causing illness or by weakening the organism so that it becomes easier prey for predators
interrelationships
beneficial - mutualism, commensalism
detrimental - relationships between organisms that may harm each others chance of survival eh parasitism, predation, competition
niche
- the way an organism lives and the role it plays in an ecosystem
- each organism has adapted to life in its habitat
- no two species share the same niche
fundamental niche
- region of the environment which a species can persist indefinitely
- no competition
realized niche
results from competition and is the area to which species are most highly adapted and commonly found
ecological niche
all factors that a species needs to survive
biomagnification
- the accumulation of non-biodegradable matter in the tissue of one organism passed along form the previous organism in the food chain
- concentration of the chemical increases with increasing tropic levels
- higher order consumers are at greater risk because they eat a large number of lower order consumers
DDT
- a synthetic insecticide that is non biodegradable
- thins egg shells
- saved a lot of humans lives from mosquito disease
- dangerous effect on many animals
