Describing the Cycling of Matter in Ecosystems

Cycling of Matter in Ecosystems

Matter Cycles in and out of ecosystems

• Matter may change forms, but it doesn't disappear

• Law of conservation of mass

• The total amount of matter on the Earth remains constant

The Water Cycle

AKA "hydrologic cycle

-Water cycles from the atmosphere, the Earth's surface, below ground, and back.

Multiple Select

In which part(s) of the water cycle listed below is water in the liquid state?

• precipitation

• condensation

• evaporation

• seepage

• runoff

Oxygen Cycle

• Remember photosynthesis and respiration?

• Oxygen is a product of photosynthesis

• Oxygen is a reactant in Cellular respiration

Open Ended

Explain how deforestation might affect the oxygen cycle.

Carbon Cycle

• Carbon is the building block of life

• Carbon moves from the atmosphere, through the food web and back to the atmosphere.

• Carbon is emitted during the burning of fossil fuels

Nitrogen Cycle

• mostly takes place underground.

• Some bacteria convert gaseous nitrogen into ammonia

• Nitrogen moves through the food web and returns to the soil during decomposition.

Multiple Choice

What is the source of nitrogen for the animal?

• decomposers

• plants

• ammonia

• nitrates

Phosphorous Cycle

• takes place at and below ground level

• Phosphorous moves through the food web and returns to the soil during decomposition.

Multiple Choice

Organic molecules all contain what element?

• oxygen

• carbon

• nitrogen

• phosphorus

Open Ended

Why is carbon dioxide called a "greenhouse gas?"

Open Ended

Why is too much nitrogen harmful to an ecosystem?

Multiple Select

Which two cycles depend directly on photosynthesis?

• water cycle

• carbon cycle

• oxygen cycle

• phosphorous cycle

• nitrogen cycle

Multiple Choice

Fossil fuels are a part of which cycle?

• oxygen

• nitrogen

• phosphorous

• carbon

Pyramid Models

How can we model energy and mass distribution in an ecosystem?

Energy Pyramid

• compare energy used by producers and other organisms on trophic levels.

• 10% RULE: Only 10% of the energy at each tier is transferred from one trophic level to the next

• up to 90% of the energy is lost into the atmosphere as heat.

Biomass Pyramid

• Biomass: measure of the total dry mass of organisms in a given area

Multiple Choice

Each levle in a food chain contains less energy than the one below it because some energy is

• added to the system

• lost as heat

• consumed by carnivores

• incorporated into biomass

Multiple Choice

The term biomass refers to the total

• dry mass of the organisms in a given area

• unused material excreted as waste

• producer to consumer ratio

• mass of all living things on Earth

Multiple Choice

What does the diagram in the picture show?

• nitrogen cycle

• water cycle

• carbon cycle

• oxygen cycle

Multiple Choice

According to the 10% Rule.....

• 10% of the energy is lost to heat when moving from one trophic level to the next

• 10% of the energy is transferred to the next trophic level

• 10% of the biomass is lost in each trophic level

• 10% of the biomass is passed on to each trophic level