Ecosystems and Biomes Populations and Communities A. An organism obtains food, water, shelter, and other things it needs to live, grow, and reproduce from its environment. B. An environment that provides the things the organism needs to live, grow, and reproduce is called it habitat. C. An organism interacts with both the living and nonliving parts of its habitat.

1. The living parts of the habitat are called biotic factors. 2. The nonliving parts of the habitat are called abiotic factors. 3. Abiotic factors include: -water -sunlight -oxygen -temperature -soil D. Population – all the members of one species in a particular area.

E. Community – all the different populations that live together in an area. F. Ecosystem – The community of organisms that live in a particular area, along with their non-living surroundings. G. Ecology is the study of how living things interact with each other and with their environment. Ecology Song

Interactions Among Organisms A. Natural Selection – Individuals whose unique characteristics are best suited for their environment tend to survive and produce offspring. B. Niche – The role of an organism in its habitat, or how it makes its living. 1. A niche also includes when and how the organism reproduces and the physical conditions it requires to survive.

C. Competition – the struggle between organisms to survive as they attempt to use the same limited resource. D. Predation – an interaction in which one organism kills another for food. 1. predator – the organism that does the killing 2. prey – the organism that is killed. E. Defense Strategies – adaptations that help organisms avoid becoming prey.

1. mimicry 2. protective covering 3. false coloring 4. warning colors 5. camoflauge top 10 power moves F. Symbiosis – a close relationship between two species that benefits at least one of the species. 1. Mutualism – a relationship in which both species benefit. Ex: Saguaro cactus and long-eared bats

2. Commensalism – a relationship in which one species benefits and the other species is neither helped nor harmed. Ex: red-tailed hawk and the saguaro cactus 3. Parasitism – involves one organism living on or inside another organism and harming it. A. Parasite – the organism that benefits. B. Host – the organism it lives on or in. Ex: tapeworms living inside the digestive system of dogs. Video 5 min.

Energy Flow in Ecosystems A. Each organism in an ecosystem fills the energy role of producer, consumer, or decomposer. B. Producer – an organism that can make its own food. C. Consumer – an organism that obtains food by feeding on other organisms. 1. herbivores – eat only plants 2. carnivores – eat only animals 3. omnivores – eat both plants and animals.

D. Decomposers – break down wastes and dead organisms and return the raw materials to the ecosystem. E. Food Chain – is a series of events in which one organism eats another and obtains energy. 1. The first organism in a food chain is always a producer. 2. 1st level consumer – the 2nd organism in a food chain. 3. 2nd level consumer – the 3rd organism in a food chain.

F. Food Web – consists of many overlapping food chains in an ecosystem. G. Energy Pyramids – shows the amount of energy that moves from one feeding level to another in a food web. 1. The most energy is available at the bottom level of the pyramid. Lion King Video IV. Biomes – A biome is a group of land ecosystems with similar climates and organisms. It is mostly the climate – temperature and precipitation – in an area that determine its biome.

A. Tropical rainforest is characterized by lots of rain. 1. The three layers are the canopy, understory, and forest floor. 2. Contain more species of plants and animals than all the other biomes combined. B. Desert is an area that receives less than 25 cm of rain per year. 1. Organisms must adapt to the lack of rain and extreme temperatures. 2. Many animals are active at night when temperatures are cooler.

C. Grassland is an area that is populated mostly by grasses and other non-woody plants. 1. Grasslands located close to the equator are called savannas. 2. Receive 25-75 cm of rain each year. 3. Soil is rich in nutrients. D. Deciduous Forest is the biome that we live in. 1. Many deciduous trees that lose their leaves. 2. At least 50 cm of rain per year. 3. Four distinct seasons.

E. Boreal Forest/Taiga 1. Most of the trees are coniferous trees or trees that produce seeds in cones and have needles. 2. Winters are very cold. 3. Summers are rainy and warm enough to melt the snow. F. Tundra is an extremely cold and dry biome. 1. Most of the soil in the tundra is frozen all year. This is called permafrost.

2. Plants have short roots and only grow during the short summer season. 3. Animals migrate south during the coldest winter months. Aquatic Ecosystems A. Freshwater ecosystems includes streams, rivers, ponds and lakes. 1. Streams and rivers have strong currents and are running water. 2. Ponds and lakes are bodies of standing, or still , fresh water.

B. Marine Ecosystems 1. Estuary – where fresh water of a river meets the salt water of the ocean. 2. Intertidal Zone – area between the highest high-tide line and the lowest low-tide line. 3. Neritic Zone – A region of shallow water which extends over the continental shelf. 4. Open Ocean – contains the surface zone and the deep zone. The deep zone is almost totally dark.