4.2 Energy Flow

Question 1

what is the initial source of energy for ecosystems?

Answer 1

Sunlight

Question 2

What does photosynthesis do?

Answer 2

convert light energy to chemical energy

Question 3

how does chemical energy in carbon compounds flow through food chains?

Answer 3

feeding

Question 4

Why is energy lost in the ecosystem?

Answer 4

The heat produced as a byproduct during cellular respiration gets lost as organisms cannot convert it to other forms of useful energy.

Question 5

What is the 10% rule?

Answer 5

10% of energy is transferred between trophic levels.

Question 6

What restricts the length of food chains?

Answer 6

energy loss between trophic levels

Question 7

definition of biomass

Answer 7

the total mass of organisms in the trophic level

Question 8

why is biomass lost as along the trophic levels?

Answer 8

not 100% of the organic matter consumed by an organism is digested.

Question 9

difference between energy flow & nutrient cycle:

Answer 9

Energy Flow
- not recycled
- continuous but variable support
Nutrient cycle
- recycled by decomposers
- limited/finite supply

Question 10

differences & similarities between food web & food chain

Answer 10

food chain
- linear
- individual occupies one trophic level only
food web
- individual may occupy many trophic levels
- more realistic
Both: arrow indicates transfer of energy