KA3.1/4 - Ecosystems & Energy in Ecosystems

Question 1

Describe the term species?

Answer 1

A species is a group of organisms that can breed to produce fertile offspring

Question 2

… is the range of populations in an ecosystem?

Answer 2

Biodiversity is the range of populations in an ecosystem

Question 3

A group of organisms of the SAME species is known as a …?

Answer 3

Population.

Question 4

Which type of organisms produces its own food (plants and some fungi)?

Answer 4

Producers.

Question 5

A … is an organism that consumes other organisms to get food.

Answer 5

Consumer. A consumer is an organism that consumes other organisms to get food.

Question 6

What terms are used to describe an animal that eats only plants, an animal that eats only animals and an animal that eats both?

Answer 6

• *Herbivore** - eats only plants.
• *Carnivore** - eats only animals.
• *Omnivore** - eats both.

Question 7

An animal that hunts other animals is known as a?

Answer 7

Predator.

Question 8

Define the term ecosystem?

Answer 8

all the organisms (the community) in a particular habitat and the non-living components with which they interact.

Question 9

A … is the role that an organism plays within a community.

Answer 9

Niche. A niche is the role that an organism plays within a community.

Question 10

Is an abiotic factor a living or non-living factor.

Answer 10

Non-living. Abiotic are non-living factors such as pH, temperature etc. and biotic is living factors.

Question 11

Plants will compete for …, … and …

Answer 11

Light, water and space.

Question 12

Animals compete for what four factors?

Answer 12

Water, food, mates and shelter

Question 13

Which type of competition occurs between individuals of the same species?

Answer 13

Intraspecific competition.

Question 14

Interspecific competition occurs between individuals of … species compete for one or a few resources they require

Answer 14

different.

Question 15

Why is intraspecific competition typically more intense that interspecific competition?

Answer 15

Intraspecific competition occurs between members of the same species and they compete for all of exactly the same resources, so are more likely to be competing.

Question 16

Explain how grazing affects biodiversity?

Answer 16

Low grazing = low biodiversity as a few dominant species prevent other species from growing.
Medium grazing = more light and space available so more species can grow increasing biodiversity.
High grazing = kills all plants but the most tolerant species reducing biodiversity.

Question 17

What do the arrows in a food chain/web represent?

Answer 17

Flow of energy.

Question 18

Only …% of the energy taken in by each organisms in the food web is used for body growth and available to be transferred to another organisms.

Answer 18

10%

Question 19

90% of the energy at each level of the food chain/web is lost due to …, … and …

Answer 19

heat energy, movement energy and undigested materials.

Question 20

State the pyramid used to represent the numbers of organisms at each stage of a food chain?

Answer 20

Pyramid of numbers.

Question 21

Explain how irregular pyramids of numbers can arise?

Answer 21

due to larger organisms supporting many organisms on them due to differences in body size, i.e. one cow supports 10-100’s of parasites.

Question 22

Why does a pyramid of energy always become narrower as they move up the food chain?

Answer 22

Because, only 10% of the energy is passed on at each step of the food chain.