Notes: Unit 10: Interactions of Living Things

Section 1: Everything is Connected Studying the Web of Life 1. Ecology is the study of the INTERACTIONS of organisms with one another and with their ENVIRONMENT

2. The Two Parts of the Environment: a) All of the organisms that live together and interact with one another make up the BIOTIC part of the environment. These are the LIVING parts of the environment. Some examples include ______b) The ABIOTIC part of the environment consists of the nonliving factors. Some examples are WATER,SUNLIGHT,TEMP,SOIL,ROCKS, OXYGEN,ATMOSPHERE Never was ALIVE or is now DEAD.

3. Organization in the Environment: The environment may seem disorganized. However, the environment can be arranged into different levels. a) Each living thing is a/an ORGANISM Any thing that can carry out life processes independently.  Example: ALLIGATOR b) Each animal is a part of a POPULATION which is a group of individuals of the same species that live together at the same time in the same place  Example: ALLIGATORS c) A COMMUNITY consists of all of the populations of species that live and interact in an area.  Example: ALLIGATORS, FISH, BIRDS, GRASS d) An ECOSYTEM is made up of a community of organisms and the abiotic factors of the community.  Example: WETLAND e) The BIOSPHERE is the part of Earth where life exists. It extends from the deepest parts of the ocean to high in the air where plant spores drift.

Ecologists  An ecologist is one who looks at how all the BIOTIC and ABIOTIC factors in an ecosystem are RELATED.  Why do ecologists study the biosphere? TO LEARN HOW ORGANISMS INTERACT WITH THE ABIOTIC PARTS OF THE ENVIRONMENT

Section 2: Living Things Need Energy The Energy Connection 4. An organism’s energy role in an ecosystem may be that of a PRODUCER CONSUMER or DECOMPOSER 5. Organisms that use sunlight directly to make food are PRODUCERS  They make food by using a process called PHOTOSYNTHESIS which is when plants use the sun’s energy to turn CO2 and WATER into molecules of OXYGEN and GLUCOSE. (Glucose is a type of sugar that is the plant’s FOOD 6. Organisms that eat other organisms are called CONSUMERS  Consumers that eat only plants are HERBIVORES - examples: ______ Consumers that eat only animals are CARNIVORES - examples: ______- Carnivores that feed on dead organisms are called SCAVENGERS - examples: VULTURES, CATFISH  Consumers that eat both plants and animals are OMNIVORES - examples: PEOPLE, BEARS 7. Organisms that get energy by breaking down dead organisms and return the raw materials to the environment are called DECOMPOSERS  examples: __BACTERIA, FUNGI SUCH AS MOLD AND MUSHROOMS

8. A FOOD CHAIN is a diagram that shows how energy in food flows from one organism to another. It demonstrates this by showing which organism EATS which. 9. A FOOD WEB is a diagram that shows the feeding relationships between organisms in an ecosystem. It consists of many overlapping FOOD CHAINS in an ECOSYSTEM 10. An ENERGY PYRAMID is a triangular diagram that shows an ecosystem’s loss of energy, which results as energy passes through the ecosystem’s food chain.  it shows the amount of ENERGY that moves from one feeding level to 3 the next in a FOOD WEB  the most energy is available at the PRODUCER level  only about 10% of the energy at one level of a food web is transferred to the next, HIGHER level

11. Balance in Ecosystems: All organisms in a food web are important for the HEALTH and BALANCE of all other organisms in the food web.

Section 3: Interactions in communities Interactions with the Environment 12. A resource that is so scarce that it limits the size of a population is called a LIMITING FACTOR  Limiting factors PREVENT a population from growing. - some examples are: not enough FOOD not enough SPACE and poor WEATHER conditions. 13. The largest population that an environment can support is known as the CARRYING CAPACITY

Interactions Between Organisms 14. Individuals and Populations Interact a) Populations contain individuals of a single SPECIES that interact with one another, such as a group of rabbits feeding in the same area. b) Communities contain interacting POPULATIONS such as a coral reef with many species of corals living in the same area. c) Ecologists have described four main ways in which organisms affect each other. They are COMPETITION, PREDATION, SYMBIOSIS AND COEVOLUTION

Predators and Prey 15. PREDATORS are animals that eat other animals. Animals that are killed and eaten by other organisms are called PREY. 16. Predator Adaptations: To survive, predators must be able to CATCH their PREY. Predators have a wide variety of methods and abilities for doing so. 17. Prey Adaptations: Prey also have many methods and abilities to AVOID being eaten, such as: - RUN away - stay in a GROUP - CAMOUFLAGE themselves, they do this by BLENDING in with the background - some can defend themselves with CHEMICALS. - The skunk and the bombardier beetle both spray predators with irritating chemicals. Bees, ants, and wasps inject a powerful acid into their attackers. - being POISONOUS or VENOMOUS .

Symbiosis 18. SYMBIOSIS is a relationship in which two different organisms live in close association with each other. a) MUTUALISM is a symbiotic relationship between two species in which both organisms benefit. b) COMMENSALISM is a symbiotic relationship in which one organism benefits and the other is unaffected. c) PARASITISM is a symbiotic association in which one organism benefits while the other is harmed. - The organism that benefits is called the PARASITE while the organism that is harmed is called the HOST

Competition 19. When two or more individuals or populations try to use the same resource, such as FOOD, WATER, SHELTER , SUNLIGHT OR it is called COMPETITION 20. Competition can happen WITHIN a population, or BETWEEN populations.

Coevolution 21. When a long-term change takes place in two species because of their close INTERACTIONS with one another, the change is called coevolution.  example: Flowers have changed over millions of years to attract POLLINATORS such as bees, bats, and hummingbirds can be attracted to a flower because of its COLOR, ODOR or NECTAR

Definitions 22. Any species that is in danger of extinction throughout all or a significant portion of it’s range At the brink of extinction now is ENDANGERED

23. Any species which is likely to become endangered within the foreseeable future Likely to be at the brink of extinction in the near future is THREATENED 24. Any species that is not native to an ecosystem is INVASIVE