B18 Organisms and their environment

Question 1

What is the principle source of energy input in biological systems

Answer 1

The Sun

Question 2

What is a food chain?

Answer 2

A food chain is a linear sequence of organisms showing who eats whom in an ecosystem, from producers to consumers.

Question 3

What is a food web?

Answer 3

A network of interconnected food chains

Question 4

What is a producer?

Answer 4

an organism that makes its own organic nutrients, usually using energy from sunlight, through photosynthesis

Question 5

What is a consumer?

Answer 5

an organism that gets its energy by feeding on other organisms

Question 6

What are the trophic levels?

Answer 6

Producer, Primary consumer, Secondary consumer, Tertiary consumer.

Question 7

What is a herbivore?

Answer 7

A herbivore is an organism that primarily eats plants.

Question 8

What is a carnivore?

Answer 8

An animal that gets its energy by eating other animals

Question 9

What is a decomposer

Answer 9

as an organism that gets its energy from dead or waste organic material

Question 10

What is a trophic level?

Answer 10

the position of an organism in a food chain and food web

Question 11

Why isn’t the transfer of energy from one trophic level to another not efficient?

Answer 11

90% of the energy is used for Respiration, movement, maintaining body temperature, some parts of the food cannot be digested

Question 12

Why do food chains usually have fewer than five trophic levels.

Answer 12

There is 90% energy loss at each level. This limited energy supply makes it difficult to sustain higher trophic levels.

Question 13

Why is it more energy efficient for humans to eat plants rather than livestock.

Answer 13

Corn —–> Cow —-> Human
100J 10J 1J

Corn —-> Human
100J 10J

If a Primary consumer that eats producers are eaten by humans then 90% of the energy from producers are not transferred, if Human eats the Primary consumer 90% of the energy from the primary consumers are not transferred, a total of 99% energy is wasted.

If Humans eat the producer 90% of energy is wasted

99%> 90% so humans gain more energy from plants

Question 14

What is combustion

Answer 14

continuous exchange of carbon between the atmosphere (via respiration and combustion), living organisms (through photosynthesis, feeding, and respiration), and the Earth’s crust (in the formation of fossil fuels), as well as the return of carbon to the environment through decomposition and the release of carbon dioxide from the burning of fossil fuels