Week #8

Question 1

What are trophic levels?

Answer 1

Group of organisms which occupy same level in food chain | Each level differs in nutritional relationship with primary energy source

Question 2

What are autotrophs?

Answer 2

Primary producers | “Self-feeders;”

Question 3

What are photoautotrophs?

Answer 3

Energy from light

Question 4

What are chemoautotrophs?

Answer 4

Energy from inorganic molecules

Question 5

What are heterotrophs?

Answer 5

Consumers | Obtain organic compounds by consuming other organisms

Question 6

T/F - A Venus fly trap is a heterotroph?

Answer 6

False - A Venus fly trap is considered an autotroph because it primarily gets it food from photosynthesis

Question 7

What are the types of consumers?

Answer 7

Herbivores, primary carnivores, secondary carnivores, detritivores, decomposers

Question 8

What are herbivores?

Answer 8

1st consumer level

Question 9

What are primary carnivores?

Answer 9

Eat herbivores

Question 10

What are secondary carnivores?

Answer 10

Eat primary carnivores or herbivores

Question 11

What are detritivores?

Answer 11

Eat decaying matter

Question 12

What are decomposers?

Answer 12

Microbes that break up dead matter

Question 13

How are the trophic levels organized?

Answer 13

Primary producers —> primary consumers —> secondary consumers —> tertiary consumers –> decomposer

Question 14

What are limiting nutrients?

Answer 14

Nutrients in shortest supply and put a limit on growth

Question 15

What are limiting nutrients for terrestrial and aquatic ecosystems?

Answer 15

Nitrogen and phosphorus

Question 16

What are limiting nutrients for algal populations in ~1/3 of world’s oceans?

Answer 16

Iron

Question 17

What is primary productivity?

Answer 17

Synthesis of organic compounds from atmospheric or aqueous carbon dioxide | rate at which energy is stored as biomass (organic material from plants and animals that can be used as a renewable energy source)

Question 18

What is Gross Primary Productivity (GPP)?

Answer 18

Rate at which primary producers incorporate energy from the sun

Question 19

What is Net Primary Productivity (NPP)?

Answer 19

Energy that remains in primary producers after respiration and heat loss

Question 20

About what percent per year of incoming solar radiant energy is captured by primary producers?

Answer 20

~1%/year (in chemical bond energy) | allows respiration to be carried out, some is lost to heat | This is the energy lost in food chains, the energy left after these processes

Question 21

T/F - Heterotrophs only have chemical-bond energy left in primary producers

Answer 21

True

Question 22

T/F - Amount of chemical-bond energy decreases as energy is passed from one trophic level to the next

Answer 22

True (think caterpillar and energy lost to feces, cellular respiration, and growth (new biomass)

Question 23

How much energy is stored as biomass as energy transfers down trophic levels?

Answer 23

10%

Question 24

T/F - The # of trophic levels is limited by energy availability

Answer 24

True

Question 25

T/F - The 10% rule is the same as the 1% sun rule

Answer 25

False, 1% is the amount of energy primary producers get from the sun (autotrophs), 10% is the amount of energy passed onto and between consumers (heterotrophs)