Chapter 4 Ecology Flashcards
Ecology def
Is the study of how living things interact to eachother and their environment
Environment
all the conditions in which the organism lives which affect the growth and development of the organism
Biosphere
Is the part of the planet where the life exists. eg. land, ocean etc.
Ecosystem
is a community of living things interacting with one another and their environment within a particular place within a particular area
Habitat
is the particular place within the ecosystem where an organism lives
Habitat example
bats- hollow trees/attics
Population
A group of individuals of the same species living together in an ecosystem.
Reasons for living in a population
safer in a group
habitat provides shelter and food
availability of a mate for breeding
Community
All populations in an ecosystem
primary source of energy
sun- light energy
Energy flow def
The pathway of energy transfer from one organism to the next in an ecosystem due to feeding
Food chain def.
A list of organisms in which each organism is eaten by the next one in the chain.
Grazing food chain
Where initial plant is living
detritus food chain
chain begins with dead organic matter.
Producers
Make their own food by photosynthesis
Consumer
get their food from plants or other animals.
Herbivore
Feed on producers
Carnivores
Feed on primary consumers
Tertiary
Feed on secondary consumer
Omnivore
Eats both plants and animals
decomposers and importance
Feed on dead organic matter
break down waste and return nutrients to the soil
Trophic level
Refers to the position of an organism in the food chain
Pyramid of numbers
A diagram that represents the number of organisms at each trophic level in a food chain.
The number in each level decreases as you go up
Body size increases
Inaccuracy of the pyramid of numbers
Doesnt take into account size of animal
Cant be drawn to scale so not accurate
Energy loss-
why does the number in each level get smaller
OR
Why are food chains short
90% of energy is lost mostly through heat energy. Energy reduces so rapidly that food chain is limited in length. Also limited in organism numbers because of this.
Inverted Pyramid
If bottom layer is a large orgnism
Parasitic Pyramid
Produces inverted/partially inverted pyramids
Because loads of flies/mites can live on one fox.
Competition def.
When organisms fight for resources in short supply
Intra competition
Same species
Inter competition
different species
Difference between Scramble and Contest competition
Scramble: Organism tries to get as much as possible (eg. ivy plant and hawthorn tree compete for light)
Contest: Active physical confrontation between 2 organism s. One wins.(eg. Badgers fight for a burrow)
Parasitism def.
Two organisms living close together. one organism benefits from the host and causes harm.
Ectoparasites vs. Endoparasites
Ectoparasites: Living on the outside of the host (eg. fleas on a dog)
Endoparasites: Living on inside of the host. (eg. Liverfluke in cattle)
Symbiosis def.
Relationship where two organisms live in close proximity to one another where at least one of them benefits. No harm caused.
Symbiosis example
Bacteria in the roots of plants.
Bacteria gets a living environment.
Bacteria fixes nitrogen into usable form.
Predation def.
The act of some animals of capturing and killing other animals for food.
eg. Ladybird-Aphid
Hawk-Earthworm
Adaptation def.
Is a structure that organisms have developed to survive.
Examples for adaptation
Zebras have stripes so lions cant tell where one ends and the other begins.
Ladybird has strong mouth and contains formic acid which is unpalatable.
Relationship between prey and predator numbers.
(See diagram in copy) Prey increases as less predators Predators increase as more food Prey decrease because they are eaten. Predator decrease because less prey ETC. ETC....
Interdependence def.
Two organisms rely on each other for survival.
Interdependence example
Bee and Flower
Bee pollinates flower.
Flower provides nectar
Abiotic factors def. and eg.
Non-living factors
Light intensity, water current, altitude, aspect.
Biotic factors def. and eg.
Living factors
Food and shelter, Predators, Prey, Decomposers
Climatic factors def. and eg.
Weather conditions
Wind, temperature, humidity
Edaphic factors def. and eg.
To do with soil
Soil type, Water content, Soil pH
Examples of environmental factors
Light intensity
Aspect
Temperature
1.Light intensity High- More plants Low- Less plants and animals 2.Aspect North-less light-less plants South-more light-more animals 3.Temperature Ideal-supports plant growth High-Desertification Low-Hibernation and immigration
Benefits of predation
controls population
Eliminates weak prey
Stops overgrazing
Strategies to avoid competition example
Daisy has short roots, dandelion has long roots
examples of adaption
beaver- has nostrils and ears that close underwater.
Fennec foxes- have large ears to let heat escape
examples of interdependence
clownfish and sea anemone- clownfish eat anenome parasites, faeces give nutrients, clownfish protected by stinging cells.
Pilot fish and shark- fish cleans algae off shark teeth
Niche
The functional role of an organism in an ecosystem
