The Biosphere – Part 1 Biology 1

What is Ecology? Ecology is the study of interactions among organisms and between organisms and their environment The biosphere contains combined portions of the planet in which all of life exists (includes land, water and air/atmosphere)

Levels of Organization

Energy Flow The sun is the main source of energy for our planet The sun makes life possible for humans, animals, plants, fungi, bacteria and other single cell organisms

Energy Flow Energy is the ability to do work All living things need energy to survive Energy transfer is never 100% efficient Energy is lost through heat More energy is lost as energy is transferred through the system

Energy Flow Energy flows through the ecosystem by changing forms Two main forms of energy are chemical and mechanical Chemical energy is stored energy in bonds and the energy is released when the bonds are broken Mechanical energy is energy of movement

Producers Producers are organisms capable of creating their own energy The process is called photosynthesis Plants are generally our main source of producers Plants use the sun's energy to create sugars

Producers Chemosynthesis occurs when organisms (usually bacteria) use chemical energy to produce energy as opposed to the sun

Primary Consumers Primary consumers eat plants If a primary consumer eats only plant they are called herbivores When a primary consumer eats plants, energy is transferred from the plant to the consuming organism Energy is transferred in the form of chemical energy Energy is lost through heat

Secondary Consumers Secondary consumers eat organisms that are primary consumers If an animal only eats other animals they are called carnivores The total amount of energy is less with the transfer from primary to secondary consumer That means there is less energy available to secondary consumers and even less to tertiary consumers (secondary consumers that eat other secondary consumers)

Decomposers and Detritivores Decomposers – an organism that breaks down nutrients in the environment Examples: bacteria and fungi Detritivores feed on the remains of dead plant and animal material Examples: earthworms, snails, crabs

Food Chains A food chain shows the transfer of energy from one organisms to another

Energy Pyramid A energy pyramid shows how much energy is transferred In an energy pyramid there are more organisms at the bottom and fewer at the top Each level is called a trophic level

Food Webs Food webs show how energy is transferred in an ecosystem

Food Webs The greater number of organisms in a food web the more stable the environment is Usually, the warmer the environment the greater number of plants and animals and the cooler, the less number

Predator-Prey Relationships Predators Are usually at the top of the food chain The bigger the predator the greater the chance are becoming endangered There is less energy available at the top of the food chain

Predator-Prey Relationships Are eaten by the predators The predator-prey relationship will cycle

Other Relationships Symbiotic relationship: two organisms living together as one organism Mutualistic: relationship between two species where both benefit

Other Relationships Commensalism: relationship where one species benefits and the other is unaffected Parasitic: relationship where one species benefits and the other is harmed

Water Cycle Like energy water is transferred throughout the environment Water can pass through several forms in the water cycle Infiltration: when water is absorbed by the soil Groundwater: water that is located underground

Water Cycle Water can pass through several forms in the water cycle Runoff: water that does not absorb into the ground, but runs off into stream, lakes and reservoirs Surface water: water that located on the surface (streams, lakes, ponds, oceans, etc) Evaporation: surface water that is heated by the sun and changes from a liquid to a gas and escapes into the atmosphere

Water Cycle Water can pass through several forms in the water cycle Transpiration: water that is evaporated from plants Water is constantly changing forms in the environment

Carbon Cycle Carbon is the molecule of life – everything living contains carbon molecules Plants use carbon molecules during photosynthesis to create carbohydrates (or energy)

Carbon Cycle When primary consumers eat plants or secondary consumers eat other organisms the carbon is transferred When organisms die (plants or animals) the carbon is broken down and used again

Nitrogen Cycle Nitrogen in the form of NH4+ or NO3- is used by plants to grow Plants use these molecules during the growing season and often times fertilizer needs to added to soil because it gets used up before it can be replaced naturally Lightening, bacteria and other processes help to put nitrogen into the soil