Unit 2 A Ecology Biotic Notes Energy Flow

Unit 2 A – Ecology – Biotic Notes – Energy Flow

• What is energy flow? • The movement of energy through a community via feeding relationships • Examples: • Food Chains • Food Webs • Trophic Pyramids

• All living things need energy • What is the main source of energy for living things? – THE SUN!!!!! • Can organisms get energy any other ways? – YES! • How? Some rely on the energy stored in inorganic chemical compounds – Ex: Mineral water

• Can all living things use the sun’s energy to make food for themselves? – NO!!! – Only plants, some algae, and certain bacteria can • These are called autotrophs

• An autotroph can make its own food – Through a process called photosynthesis • We will talk about this later • Another word for autotroph is producer – A producer makes its own food • The 2 words are interchangeable!!!

• 2 Types of Producers 1. Get energy from the sun 1. Autotrophs that use the sun do photosynthesis 1. Photo = light 2. Synthesis = makes 3. Photosynthesis takes carbon dioxide, water, and energy to make glucose (a sugar) that is the plants food 2. Get energy from chemicals 1. Autotrophs that use chemicals do chemosynthesis 1. Chemo = chemicals 2. Synthesis = makes 3. Mainly done by bacteria

• Not all organisms can use the sun to make energy – They need to “eat” – These include • Animals • Fungi • Many Bacteria

• Organisms that rely on others as their source of energy are called heterotrophs – AKA: Consumers • There are 5 main types of consumers: 1. 2. 3. 4. 5. Herbivores Carnivores Omnivores Detritivores Decomposers

• What are herbivores? – Eat ONLY plants – Examples: • Cows • Caterpillars • Deer

• What are carnivores? – Eat ONLY animals – Include: • Snakes • Dogs • Owls

• What are omnivores? – Eat BOTH plants and animals – Include: • Humans • Bears • Crows

• What are detritivores? – Eat plant and animal remains and other dead matter Eat dead stuff!!! • This dead matter is called detritus – Includes: • • Mites Earthworms Snails Crabs

• What are decomposers? – Break down organic matter – Include: • Bacteria • Fungi

• Energy flows through an ecosystem in 1 direction 1. Sun/Inorganic Compounds 2. Producers 3. Consumers

• What is a food chain? – A series of steps in which organisms transfer energy by eating or being eaten – 1 directional

• What is a food web? – Nothing is as simple as it seems – Feeding relationships are more complex than just a single food chain • Network of relationships • Many organisms can be eaten by other organisms, etc… – A food web links all the food chains in an ecosystem together • Usually contains several food chains within a single food web

• What is a trophic level? – Each step or level is considered a tropic level – Producers make up the first level – Consumers make up the 2 nd, 3 rd, 4 th, etc. levels