habitat - an environment that provides the things an organism needs to live.

biotic factor - a living part of an organism’s habitat. i.e. grass, plants, seeds, fruit, worms, bacteria, other animals

abiotic factor - a non-living part of an organisms habitat. i.e. water, sunlight, oxygen, temperature, soil

photosynthesis - the process in which plants use water along with sunlight and carbon dioxide to make their own food.

species - a group of organisms that are physically similar and can produce offspring.

population - all the members of one species in a particular area. The “count” of one species in an area.

ecosystem - the community of organisms that live in an area along with their non-living surroundings.

ecology - the study of how living things interact with each other and their environment.

population density- the number of species in a specific area

limiting factor - a factor in the environment that causes the population to decrease or go down. i.e. food and water, living space, weather

natural selection - a process in which organisms best suited to the environment tend to survive; survival of the “fittest.”

adaptation - a change in the body or behavior of a species making it easier to survive. i.e. poisonous jellyfish, camouflage bugs, protective shell, etc.)

niche - the “job” an organism in its environment. i.e. plants produce oxygen, bacteria decompose waste, hawks control mice population, etc.

competition - the struggle for survival between living things for the limited resources.

predator - an animal that hunts and eats other animals; i.e. lions are the predators of zebras

prey - an animal that is hunted or eaten by other animals; i.e. mice are the prey of cats

symbiosis - two organisms living together. There are three kinds of symbiosis: mutualism, commensalism and parasitism.

mutualism - a kind of symbiosis in which both organisms help each other (bees getting pollen from flowers; helps the flower pollinate and bee can make honey)

commensalism - commensalism is a kind of symbiosis in which one organism benefits without harming the other (bird builds nest in a tree to protect itself from ground animals, three not harmed)

parasitism - Parasitism is a kind of symbiosis in which one organisms gains and the other is harmed (tick on dog)

parasite - the organism that benefits by living off of another organism (tick)

host - the organism that a parasite “lives off of” and harms

succession - a series of changes that occur in a community over time; i.e. a field becomes a forest over time

consumer - an organism that gets its energy (food) by eating another organism.

herbivore - an animal that only eats plants

carnivore - an animal that eats animals

omnivore - an animal that eats both plants and animals

scavenger - a carnivore that eats dead animals

decomposer - an organism that breaks down waste and dead animals

food chain - a series of events in which one organism eats another to get energy

food web - overlapping food chains in an ecosystem

energy pyramid - a diagram that shows the amount of energy that moves from one feeding level to another in a food web.

water cycle - the process in which water moves from the Earth’s surface to the atmosphere and back in a repeating cycle.

condensation - when a gas changes into a liquid; i.e. water vapor condensing into a cloud.

precipitation - rain, sleet, snow or hail

dispersal - the movement of organisms from one place to another

climate - the weather in an area over a long period of time.

more to come for next chapter....