Weeks to TAKS- Week Six: Objective 3 9d, 12b,e Energy Flow in Ecosystems

Energy and matter flow through ecosystems Radiant energy from the sun is converted to chemical energy in the form of glucose (sugar) by photosynthesis in the chloroplasts of plant cells. Autotrophs (plants/producers) use this energy in respiration. The plant’s mitochondria take that sugar and break it down into ATP that the plant can use to carry out daily life activities.

Part of the energy produced is stored in chemical bonds of the plant and part of it is released as heat to the environment. Heterotrophs eat these producers. The energy stored in their chemicals bonds is used to carry out daily life functions. Photosynthesis ProducerPrimary Consumer Secondary consumer Tertiary consumer Decomposer Heat lost through respiration Nutrients returned to environment

A food chain, shown above, shows one path the energy can take. A food web is a collection of several food chains, linked together. WheatMouse Snake Owl

A food (or energy) pyramid is another way to represent this information. The pyramid gets its shape from the fact that the greatest amount of energy in the ecosystem is stored in the producers. (There is more grass than grasshoppers, and there are more grasshoppers than frogs.) There are very few tertiary consumers in ecosystems because it takes a lot of energy feed one.

Toxins(poisons) can build up in the food chain. They are the least concentrated in the producers, but can build up in the bodies of animals as they feed. The higher an animal is on the food pyramid, the more poision he has consumed.

Niche-Animal’s role in the ecosystem. Types of niches: Herbivore-eats only plants/producers, Omnivore-eats both plants and animals, Carnivore- eats consumers only (meat), Predator-hunts, Prey-what is being hunted, Decomposer-usually fungus or bacteria that eat dead material and returns nutrients to the environment (may not be included in food webs and pyramids).

Symbiosis: Organisms can have dependent relationships. Mutualism(+,+)-both or organisms benefit from the relationship. Remoras clean sharks. The remoras get food and protection. The sharks get clean. Commensalism (+,0) –one organism benefits, the other is not effected. Spanish moss grows on trees receiving light and nutrients from the air. The tree is not helped or harmed. Parasitism(+,-)- one organism benefits, the other is harmed. The tick receives food, the dog is bitten.