3.1 interactions

Chlorophyll: a pigment found in plants and algae that is used to absorb sunlight for photosynthesis.

Photosynthesis: the process of using light energy to synthesis glucose from carbon dioxide and water to produce chemical energy.

Carbohydrate: organic compounds occurring in living tissue that contain carbon, hydrogen, and oxygen (or example, starch, cellulose and sugars such as glucose); carbohydrates can be broken down in the process of respiration to release energy.

Consumer: an animal which feeds on other organisms to gain energy from food.

Algal Bloom: a rapid increase in a population of algae caused when the ecosystem becomes in balance due to excess fertilizers entering the ocean and referred to as a dead zone.

Community: all different populations interacting in one habitat at the same time.

Mutualism: a relationship between two different organisms where both organisms benefit.

Predation: a relationship between two organisms where a predator hunts, kills and eats a prey.

Predator: an organism that hunts and kills. e.g. tuna or shark

Prey: an organism that is being predated (hunted). e.g. sardine or anchovy.

Parasitism: a relationship between two organisms where the parasite obtains benefit at the expense of the host.

Parasite: an organism that obtains nutrients from their host. e.g. sea lice or nematodes.

Competition: a relationship between two organisms where both species are negatively affected as they are trying to use the same resources.

Symbiosis: a relationship between two or more organisms of different species which live physically close to each other.

Commensalism: a relationship between two organisms where one organism benefits and the other is neither harmed nor benefited.

Ectoparasitic: a parasite that lives on the outside of the host. e.g. sea lice

Endoparasitic: a parasite that lives inside of its host. e.g. nematode

Phoresis: a commensal relationship where one organism attaches itself to another in order to travel. e.g. algae or barnacles

Autotroph: an organism that can capture the energy in light or chemicals and use it to produce carbohydrates from simple molecules such as carbon dioxide.

Chemosynthesis: the production of organic compounds by bacteria or other living organisms using the energy derived from reactions with inorganic chemicals such as hydrogen sulfide.

Heterotroph: an organism that cannot make its own food and instead relies on consuming other organisms; all animals; fungi and protozoans are heterotrophic; as well as most bacteria.

Primary Productivity: the rate of production of new biomass through photosynthesis or

chemosynthesis

Food Chain: a way to describe the feeding relationships between organisms.

Herbivore: an animal which feeds only on producers (plant or phytoplankton)

Carnivore: an animal which feeds on other animals

Predator: an animal which hunts, kills and eats other animals

Prey: an animal which is being hunted and eaten by predator

Omnivore: an animal which feeds on other animals and on producers.

Decomposers: bacteria and fungi which break down dead organic matter and release the nutrients back into the environment.

Food Web: a way to show all the different feed relationships in an ecosystem.

Biomass: the mass of living material in an area; it can be measured as a dry mass without water or wet mass with water. Units such as gC/m2/month or year or calories (C) or Joules (J).

Trophic level: the position an organism occupies in the food chain or food web.

Apex predator: an organism at the end of the food chain which has no natural predators.

Trophic Level: is the "feeding level/position" in a food chain or food web

Ecosystem: the living organisms and the environment with which they interact