Biology chapter 4

a group of various species that live in the same place & interact with one another.

a community along with the living and non living enviroment.

a web of relationships

relationships between organisms

living factors that in an ecosystem. they also include once-living things such as dead organisms & the waste of an organism

the physical or nonliving factors of an enviroment examples are oxygen, water, rocks, sand, sunlight, temperature & climate.

the place where an organism lives.

the variety of organisms in a given area

• -physical factors
• -high or low temperatures
• > these lower biodiversity
• -limited food or water

are more often able to resist damage

the replacement of one kind of community by another at a single place over a period of time

the first organisms to appear in a newly made habitat are often called pioneer species. They change the habitat in such a way that other species replace pioneer species. often new species replace pioneer species.

in such a way that the ecosystem is restored to equilibrium.

climate

the average weather conditions in an area over a long period of time

a large region characterized by a specific kind of climate & certain kinds of plant and animal communites

• temperature and precipitation
• precipitation also determines the kinds of species that are found in a biome

• by latitude into tropical, temperate, & high- latitude biomes
• latitudes Temperate 30 to 60 degrees tropical near equator 60 degrees or higher high latitude

it affects the amount of solar energy that a biome receives & thus affects the biomes temperate range.

• because of location all are warm.
• tropical rain forests & savannas & tropical deserts

• receive large amounts of rain & are warm all year.
• they have the greatest biodiversity of any land biome. at least half of earth's species of land organisms live in tropical land forests.

tropical grasslands. get less rain then rain forest. long dry season and short wet seasons. the most well known are in eastern africa

get very little rain. they have less water & have few plants and animals.

• - have a wide range of temperatures throughout the year
• - temperate grasslands
• -temperate forests
• -temperate deserts

have moderate precipitation & cooler temps. than savannas. often highly productive when used for agriculture.

grow in mild climates that receive plenty of rain. Deciduous shed leaves in fall because of cold winter. Evergreen do not.

receive little precipitation. they have a wide temperature range throughout the year.

• have cold temperatures. coniferous forest in cold wet climates > taiga
• winters are long and cold. most precipitation falls in summer
• tundra gets very little rain so plants are short most water is frozen.

• not usually called biomes most often referred to as aquatic ecosystems.
• - organized in fresh water ecosystems, wetlands, estuaries, & marine ecosystems

located in bodies of fresh water such as lakes, ponds, & rivers. variety of plants, fish, arthrpods, mollusks, & other inverebrates

provide a link between the land & fully aquatic habitats. water loving plants dominate. many species of birds, fishes, & plants are supported. Important because they moderate flooding and clean water that flows through them..

is an area where fresh water from a river mixes w/ salt water from an ocean. productive because they constantly receive fresh nutrients from rivers & the oceans

are found in the salty water of the oceans.

the sun.

change light energy from the sun into energy that they can use to grow. examples plants & algae

the basic food source for an ecosystem.

organisms that eat other organisms instead of producing their own food.

are organisms that break down the remains of animals. ex. algae and fungi

from the sun to the producers to consumers to decomposers.

Each step in the transfer of energy through an ecosystem.

In ecosystems energy flowing from one trophic level to the next.

producers

plants, algae, & some bacteria.

herbivores which eat producers.

some carnivores are on the 3rd trophic level because they eat herbivores..

any animal that eats another animal

other carnivores that eat carnivores.

animals that are both herbivores and carnivores, such as bears

a complicated interconnected group of food chains.

yes, but some energy that is used dissipates as heat into the enviroment & is not recycled.

trophic levels starts with Producers with the most energy then herbivores, small carnivores, and then large carnivores.

the lowest, producers.

a triangular diagram that shows an ecosystem's loss of energy which results as energy passes through the ecosystem's food chain is called an energy pyramid.

water, carbon, oxygen, nitrogen, & phosphorus. an ecosystem must be able to cycle these kinds of matter in order to support life.

continuously moves water between the atmosphere the land and the oceans

• - water vapor condenses & falls to earths surface as precipitation
• - some of this water percolates in to the soil & becomes groundwater. others runs across the surface or earth into rivers, lakes, & oceans.
• - then, the water is heated by the sun & re-enters the atmosphere by evaporation. Water also evaporates from trees.

process of water evaporating from trees and plants.

carbon & oxygen cycles.

the continuous movement of carbon from the nonliving environment into living things & back.

animals, plants & other photosynthesizing organisms

• -plants use the CO2 in the air to build organic molecules during photosynthesis.
• - during photosynthesis oxygen is released into the surroundings. Many organisms such as animals use this oxygen to help break down organic molecules which releases energy & CO2 then plants can use the CO2 in photosynthesis. Carbon is also released in the air through combustion.

The burning of a substance. The burning of fossil fuels releases CO2 in the atmosphere. burning things like oil & coal.

must be cycled through an ecosystem so that the nitrogen is available for organisms to make proteins

the process in which nitrogen circulates among the air, soil, water, & organisms in an ecosystem.

• most organisms cannot use nitrogen gas. It must be changed into a different form.
• A few bacteria have enzymes that enzymes that can break down N2. These bacteria supply the nitrogen that all other organisms need.
• the bacteria splits N2 & then binds nitrogen atoms to hydrogen to form ammonia NH2. Nitrogen may be fixed by lightening. but more is fixed by bacteria. Nitrogen fixing bacteria lives in the soil & on the rots of some plants. it is also fixed when humans burn fuels in vehicles & industrial plants.

the process of combing nitrogen w/ hydrogen to form ammonia

assimilation. its the process in which plants absorb nitrogen.

nitrogen from animal waste or decaying bodies is returned to the soil by bacteria. Ammonia is then converted to nitrite & then nitrate by the process of nitrification. In denitrification nitrate is changed to nitrogen gas which returns to the atmosphere.

phosphorus & it must be cycled in order for an ecosystem to support life.

the movement of phosphorus in different chemical forms from the surroundings to organisms & then back to the surroundings. it is often found in soil & rocks as calcium phosphate, which dissolves in water to form phosphate. the roots of plants absorb phosphate, humans & animals that eat the plants reuse the organize phosphorus. When they die phosphorus is returned to the soil.