B2b

Question 1

What is a pyramid of biomass?

Answer 1

• a pyramid showing the mass of living material at each stage of the food chain
• basically the weight of all the organisms at one level if you put them together
• the pyramid uses the dry biomass

Question 2

What is a pyramid of numbers?

Answer 2

-each bar on the pyramid of numbers shows the number of organisms at that stage of the food chain

Question 3

What is it a pyramid of biomass more difficult to make?

Answer 3

-pyramids of biomass require the dry mass of an organism, which requires killing the organism to find out

Question 4

What is a trophic level?

Answer 4

-feeding level

Question 5

Where does the energy initially come from?

Answer 5

-the sun

Question 6

How is energy lost in the trophic levels?

Answer 6

-to the surroundings as heat
-respiration
-waste products (egestion-food that can not be digested and passes out as feces, excretion-releasing waste products of bodily process
-

Question 7

Why can you not usually have more than 4 or 5 trophic levels?

Answer 7

-there is not enough energy to further tropic levels

Question 8

What is the formula for energy flow efficiency?

Answer 8

=energy available to the next level/energy that was available to the previous level

Question 9

What is an ecological niche?

Answer 9

• a species ecological niche is how it fits in to its ecosystem.
• it depends on things like where the individual lives and what they feed on

Question 10

What is intraspecific competition?

Answer 10

-organisms of the same species competing for resources

Question 11

What is interspecific competition?

Answer 11

-organisms of different species competing for resources

Question 12

What is a parasitic relationship (give examples)?

Answer 12

• parasites live off a host
• they take what they need without giving back and often harm the host
• e.g.tapeworms absorb nutrients leading to malnutrition, fleas

Question 13

What is a mutualistic relationship (give examples)?

Answer 13

• both organisms benefit
• e.g. insects and plants, insects pollinate the plant, the insect gets nectar
• e.g. ‘cleaner species’–oxpeckers living on buffalo, oxpeckers eat pest off the buffalo and also alert it of any predators

Question 14

Which competition has a bigger impact?

Answer 14

• intraspecific competition often has a bigger impact on organisms
• because individuals of the same species have exactly the same needs lots of resources (food, shelter, mate)