3.2 Energy, Producers, and Consumers
Primary Producers
Basically, organisms need energy for growth and reproduction. Without energy, there would be no life on earth. Energy comes from the sunlight, which is the most ultimate source of energy. It's impossible for an organism to create energy. Autotrophs are organisms who use solar/chemical energy to produce food by assembling inorganic compounds into complex organic molecules. They also store energy, so that other organisms can eat them.
Primary sources are energy compounds that are later used by other organisms. They are the key essential to the flow of energy.
Energy from the Sun
Photosynthesis, captures energy from light, and uses it to power chemical reactions that covert carbon dioxide+water which would equal carbohydrates+oxygen. Without photosynthesis, you wouldn't be able to breathe.
Life Without Light
Chemosynthesis, is chemical energy used to produce carbohydrates. It is usually found deep in the ocean, or in a harsh enviroment. Biologists found organisms around volcanic vents on the deep ocean floor, with no light for photosynthesis. With no light, they tried to research what the primary sources were, which is chemosynthesis.
Consumers
Consumers are also known as heterotrophs, because they have to get energy and nutrients from other organisms, and deeply rely on it. They are animals, fungi, bacteria, etc. that can't use energy from the enviroment as their primary sources. There are also more than one groups of consumers.
-Carnivores=kill and eat other animals
-Herbivores=absorbs energy by eating plant leaves, roots, seeds, and fruits.
-Scavengers=eat food that has been killed by predators or have already died.
-Omnivores=eat both animals and plants.
-Decomposers=feed by chemically breaking down organic matter. Recycles nutrients.
-Detritivores=digest decomposers that live on detritus particles. Chews and grinds them into very small pieces. (snails, shrimp, worms, crabs, mites, etc.)
Consumer categories don't explain the real complexity of nature. Organisms in nature usually do not stay inside their categories the ecologists place them in. The food chain/ web is very complex, the one's we see are simplified.
3.3 Energy Flows in Ecosystems
Food Chains and Food Webs
A food chain is a series of steps in which organisms transfer energy by eating and being eaten. Food chain's vary in length.
Phytoplankton are aquatic food chains, primary producer of floating algae.
Food Webs and Disturbances
Food webs are difficult to predict how exactly they would respond to an enviromental change. Enviromental disturbances happen, and it really effects the food webs in a terrible way by messing everything up. Effects of disturbances can be dramatic.
Zooplankton are krill, which is a small group of swimming animals that feed on marine algae.
Recently, krill has been slowly becoming extinct and dropping population. At the same time, huge amounts of ice around antarctica in the sea has been melting. With less ice, there is a result of fewer algae that grow beneath.
Trophic levels and Ecological Pyramids
Ecological pyramids show amount of energy within each trophic level.
Pyramids of energy
small portion of energy that passes a trophic level, is stored in body of organism on next level. The remainder is considered heat.
-Pyramids of Biomass=total ammount of living tissue within a trophic level
-Pyramids of numbers=to know the number of organisms on each level.
