Biology 20IB - Chp. 1: Energy flow in the ecosystem

Ecology

Study of biotic and abiotic factors and how they interact

Examples of biotic factors

• Competition

• Bacteria

• Disease agents

Examples of abiotic factors

• Water

• pH

• Humidity

• Inorganic nutrients

Autotroph

Organisms that can produce their own food.

Producer

Self-feeder(autotroph) and can convert inorganic matter to organic matter through light energy

Chemosynthesizer

Autotroph and can convert inorganic matter to other forms of inorganic matter through the chemical bonds of the inorganic matter

Consumer

Consumes either autotrophs or heterotrophs

Primary consumers

Consumes plants (herbivores)

Secondary consumers

Consumes herbivores

Tertiary consumers

Consumes secondary consumers and sometimes other tertiary consumers

Quaternary consumers

Consumes tertiary consumers

Apex predator

The final consumer in the chain

IB: Holozoic nutrition

Nutrition the occurs in organisms that intake food/liquid inside their body

Eg. Humans

Extremophile

Organisms that exists in extreme conditions. Usually bacteria.

Eg. Cyanobacteria (Blue-green algae)

IB: Saprophytes

Enzymes are secreted on the food sources and once it’s digested, the products are absorbed through roots; external digestion

Chemosynthesizer

Certain microbes create energy through chemical reactions without energy of the sun; autotrophs

IB: Mixotroph

An organism that can use different sources of energy and carbon instead 1 tropic mode

Decomposer

Obtains nutrients from breaking down dead organic matter and tranferring it into the biochemical cycle

Trophic level

Feeding level where energy and matter is tranferred. Usually 10% from the previous level is transferred.

Food chain

A linear depiction of energy transfer in an ecosystem.

Grazer food chain

Starts with a producer, usually plants

Food web

Interactions of multiple food chains and show diversity of food sources

Food pyramid/Ecological pyramid

Depict energy transfer and energy loss through trophic levels

Pyramid of numbers

Depicts a number of organisms needed to support the level above it

Pyramid of biomass

Depicts the mass of organism by measuring dehydrated organic tissue (mass of organism after all water is removed)

Pyramid of energy

Depicts the energy of biomass at each trophic level

Calorimeter

Energy is calculated by combusting the tissue to determine the number of calories (J)

Biomagnification

A build up of toxins in a food chain because of an organisms inability to breakdown of toxin

Equation to determine the amount of toxin in an organism

Amount of toxin = concentration (1 ppm → 1 mg/kg) x mass of organism (kg/L)