4.2 Energy Flow

Question 1

Light

Answer 1

Is the initial energy for all communities. Energy enter autotrophs and is used or changed into other forms of energy and leaves the ecosystem again. Energy stored in the products of photosynthesis by autotrophs is gradually used up as it makes it way through the trophic levels.

Question 2

Food Chains

Answer 2

the transfer of the sun’s energy from producers to consumers as organisms feed on one another.

Question 3

Trophic Level

Answer 3

is the position that an organism occupies in a food chain - what it eats and what eats it. As energy is transferred from one level to the next only 10% is used for growth, the rest is used for other metabolic activities and waste e.g. respiration.

Question 4

Food Web

Answer 4

is the interconnected pattern of food chains in a community.

Question 5

Pyramid of Energy

Answer 5

is a graphic representation of the amount of energy trapped per unit time and area in different trophic level of a food chain with producers at the bottom and tertiary consumers at the top. Values in kJ/m2/year. The first bar represents the gross primary production and the next expresses the energy ingested as food by primary consumers and so on.

Question 6

Pyramids of Numbers

Answer 6

the width of each level represents the number of organisms at that level. However, these aren’t the most effective representation e.g. population in a tree

Question 7

Order of Trophic Levels

Answer 7

Producer, Primary Consumer (herbivore), Secondary Consumer (carnivore), Tertiary Consumer (carnivore)