Unit A: Energy & Matter Exchange in the Biosphere

Section 1.0-1.2

What is energy used for?

Used to grow, maintain body process, reproduce, move, ect

Energy comes from carbohydrates and other macromolecules

What are producers? (autotrophs)

Organisms that can photosynthesis

They produce organic compounds as food for themselves and other organisms (ex: plants, algae, certain bacteria)

What is albedo?

How much of the radiant energy is abosrbed? (how much comes from clouds, land and ocean?)

Amound of energy that is reflected by a surface - 30% if reflected (not all produces get the radiant energy)

19% is aborbed by clouds (some heat the atmosphere some radiate back into space)

51% is abosrbed by land and ocean

Only 1-2% is used for photosynthesis

What are chemosynthetic producers? (also autotrophs)

For microorganisms that don’t have light they use the energy in chemical nutrients to convert carbon into carbohydrates - often in extreme conditions

What are consumers? (heterortrophs)

Organisms that have to consume autotrophs or other herterotrophs (cannot make thier own food)

What is the First Law of Thermodynamics?

Energy cannot be created or destroyed; it can be transferred from one form to another

Ex: solar energy to producers; chemical energy from producers to consumers to decomposers

What is the Second Law of Thermodynamics?

Energy conversion is not 100% efficient - some energy is lost as sound heat, or ect.

What is a food chain?

Shows a linear pathway of the flow of energy through all trophic levels

very basic - don’t show a lot of information in the ecosystem

What is a food web?

More complex and more accurate models

Give a more detailed account of the interactions between species - interactions/interconnections and diversity of food sources

What is the trophic levels?

The feeding levels that are identified by the number of energy transfers that have taken place from the original solar energy entering a system.

What is Rule of 10?

Efficiency of energy transfer from one level to another is low

Only 10% is transferred to each trophic levle (90% of energy is transferred or “wasted”)

Each trophic level will requre greater volume of food to obtain the necessary energy to survive.

Pyramid of Numbers

Compres the number of individuals in each trophic level - shows the # of organisms at one level to see how many can support the other level

SIZE MATTERS - move up size increases, number of them decrease

How do the pyramids of numbers inverted work?

Small number of LARGER organisms (lower trophic levels) can support larger number of SMALLER organisms (higher trophic levels)

ex: a tree can support many birds and insects

Pyramids of Biomass (dry mass of tissue and measued in g/m²)

How the amount of biomasses changes as energy is transferred from one trophic level to another.

More accurate - gives better representation of energy transer through trophic levels

inverted pyramids can occur - Phytoplankton and zooplankton

Pyramid of Energy

Shows the total amount of energy transferred trhough each trophic level

Calculate by a calorimeter - combusts tissue to determine the number of calories in the biomass

Shows how little energy is left at the highest trophic level

What is bioamplification?

Pollutants that build up and transfer from one energy level to the next

Greater the trophic level — greater the biomagnification