Ch.5 Study Guide Flashcards
Difference between biotic and abiotic factors
abiotic: nonliving things that affect the organism
biotic: forms of life that the organism interacts with
2 examples of biotic and abiotic factors
biotic: plants and bacteria
abiotic: water and sunlight
Difference between a habitat and nice
a habitat is where an organism lives where as its niche is its role it plays within that habitat
Explain how evolution occurs through natural selection
natural selection is a process that determines which species will reproduce and pass on their genes to the next generation (survival of the fittest), and as a result, evolution occurs due to the changes seen in the genes and characteristics over time
An example of evolution/natural selection
peppered moths
Define a polyploidy and explain why it’s important in plants
a condition in which the number of sets of chromosomes in plants’ cells are increased— cannot reproduce with closely related species that have different # of sets of chromosomes
Explain coevolution and give two examples
concept that two or more species can reciprocally influence evolutionary direction of the other
ex. ) grazing animals and grass species
ex. ) darwin’s orchid and sphinx moth
Explain the difference between interspecific competition and intraspecific competition
interspecific competition is competition between organisms of different species where intraspecific competition occurs between organisms of the same species
5 types of organism interactions
- predation
- competition
- symbiosis
- commensalism
- mutualism
Predation
interaction where one animal kills/eats another
Competition
interaction where two organisms compete to obtain the same limited resource
Symbiosis
close, long lasting, physical relationship between two different species– at least 1 benefits
Commensalism
relationship in which one organism benefits and the other isn’t affected
ex.) remoras and sharks
Mutualism
relationship in which both organisms benefit
ex.) crocodile and egyptian plover bird
Parasitism
relationship in which one organism benefits and the other one is harmed
ex.) fleas
Explain the difference between an ecosystem and a community
a community is an assemblage of all interacting species in area
whereas an ecosystem is a define space in which interactions take place between a community with its complex interrelationships, and its physical environment
3 major categories of organisms define by ecologists
producers, consumers, and decomposers
Producers
organisms that are able to use sources of energy to make organic material
Consumers
organisms that require organic matter as a source of food; consume organic matter in order to grow and survive
Decomposers
organisms that digest organic molecules in detritus into simpler organic compounds while absorbing soluble nutrients
Describe how energy flows through the environment
each step in the flow of energy of an ecosystem is a trophic level; only 10% of energy is transferred
Explain the difference between a food chain and a food web
a food chain is the series of organisms involved in the passage of energy from one trophic level to the next who eats who
whereas a food web is intersecting and overlapping food chains (more complexity and diversity)
Biogeochemical cycles
Carbon cycle, phosphorus cycle, and nitrogen cycle
Carbon cycle
cyclic flow of carbon from the atmosphere to living organisms then back to the atmospheric reservoir
Phosphorus cycle
released by erosion then dissolves in water —> plants —> whatever consumes the plants obtains it
decomposers thus recycle phosphorus compounds back into the soil
**ULTIMATE RESOURCE OF PHOSPHORUS ATOMS IS ROCK
Nitrogen cycle
cycling of nitrogen atoms between abiotic and biotic ecosystem components
Significance of carbon cycle
in order for plants to photosynthesize => grow => animals eat plants
respiration breaks down organic molecules into CO2 and H2O
Significance of nitrogen cycle
nitrogen fixing bacteria allows plants to use nitrogen after conversion to ammonia NH3
Significance of phosphorus cycle
plants use phosphorus to construct necessary molecules, necessary for animals when consuming other animals, dissolved in water after erosion, decomposers recycle phosphorus back into the soil
Explain how humans are impacting nutrient cycles
water withdrawl (groundwater depletion), agriculture and urbanization (increased runoff, flood risks, soil erosion, and decreased infiltration), destruction of wetlands (stops natural water purification process), and pollution of water sources
