Mrs. Geist Biology, Fall Swansboro High School

How do organisms obtain energy? Energy: the ability to cause change or do work Obtaining Energy Producers: make their own food. A.k.a. autotrophs. Consumers: eat other organisms. A.k.a heterotrophs. Herbivores: eat producers, such as plants and green algae (ex: cow) Carnivores: eat other consumers (ex: wolf) Omnivores: eat both producers and consumer (ex: humans) Scavengers: eat animals that have already died (ex: vulture) Decomposers: break down dead or decaying organisms (ex: fungi, some bacteria)

Flow of Matter and Energy in Ecosystems Food chain: a model that scientists use to trace the flow of energy and matter (i.e. nutrients) in an ecosystem. Ex: sun  grass  cows  human  wolf  bear  vultures Energy source  producer  primary consumer  secondary consumer  tertiary consumer  scavenger Food web: complex model of overlapping food chains Energy pyramid: amount of available energy decreases as you go up in trophic levels

Food Web

Energy Pyramid

Water Cycle Evaporation: water from lakes and oceans becomes water vapor in the air Condensation: water vapor condenses on dust in the air and forms clouds Precipitation: further condensation results in rain, ice, or snow Natural Processes recycle water Plants and animals need water for survival. Plants lose water through transpiration. Animals breathe out water vapor and perspire or urinate.

Water Cycle

Carbon Cycle Photosynthesis: autotrophs utilize sun and CO2 gas to form sugars Heterotrophs feed directly or indirectly on autotrophs to obtain carbon. Cellular respiration releases energy from glucose and releases CO2 back into the air.

Carbon Cycle

Ecology Ecology: the study of the relationship between living things and their environment Habitat: where an organism lives Niche: strategies and adaptations a species uses in its environment Obtaining food and shelter How and where it survives Where it reproduces No two species can occupy the same niche at the same time

Symbiosis Symbiosis: close relationship between 2 organisms. 3 types: Mutualism: both organisms benefit. Commensalism: one organism benefits; the other is neither harmed nor helped. Parasitism: one organism benefits; the other is harmed Test your knowledge with the “Symbiosis Worksheet”

Levels of Organization in an Ecosystem Organism: a living thing Population: a group of organisms of the same species living in the same area at the same time Community: all of the populations of a different species in the same place at the same time Ecosystem: living organisms that interact with each other and the abiotic factors in a given area Biotic: living things. Ex: plants and animals Abiotic: non-living things. Ex: temperature, climate, soil, rocks. Biosphere: the life-supporting portion of Earth

Levels of Organization in an Ecosystem

Carrying Capacity Carrying capacity: the amount of organisms an environment can support Limiting factors: any biotic or abiotic factor that restricts the existence, numbers, reproduction, or distribution of organisms. Ex: elevation, temperature, climate, soil chemistry, space, water, nutrients/food, sunlight Tolerance: an organism’s ability to withstand fluctuations in biotic and abiotic environmental factors

Succession Primary succession: occurs on an area of newly exposed rock or sand or lava or any area that has not been occupied previously by a living (biotic) community. First species to arrive are called pioneer species. Ex: lichens (algae and fungus living together) Secondary succession: takes place where a community has been removed ex: in a plowed field or a cleared forest Climax community: populations of plants or animals remain stable and exist in balance with each other and their environment. Final stage of succession

Primary Succession

Secondary Succession

Factors affecting Population size Density-independent factors: affect the population in the same proportion no matter the number of individuals (population size). Density-dependent factors: affect the population more or less depending on the population size