Ecosystems and abiotic factors

Question 1

ecosystem

Answer 1

all the living organisms and the non living components/the environment in an area

Question 2

organism

Answer 2

a single living individual

Question 3

population

Answer 3

all the organisms of the same species in an area

Question 4

community

Answer 4

all the populations/living organisms in an area

Question 5

habitat

Answer 5

a place where an organism lives

Question 6

environment

Answer 6

all the conditions that surround a living organism, including the other living things and the physical surroundings

Question 7

abiotic

Answer 7

non living elements of an ecosystem

Question 8

biotic

Answer 8

living elements of an ecosystem

Question 9

What level of an ecosystem do abiotic and biotic factors affect?

Answer 9

the communities

Question 10

What do factors in the environment affect?

Answer 10

the distribution of living organisms

Question 11

living environmental factors (3)

Answer 11

prey

competitor

predator

Question 12

non-living environmental factors (9)

Answer 12

light intensity 
(some plants evolved for growth in bright sunlight, such as cacti, while other need shade)

average temperature
(animals and plants have evolved to grow healthily at their optimum temperatures)

average rainfall/moisture levels
(many plants can’t survive in waterlogged soil as their roots can’t respire, other plants need high moisture levels)

oxygen levels in water (higher in unpolluted water)/carbon dioxide levels on land
(areas with more carbon dioxide are more likely to have healthier plants, healthy lakes have high levels of oxygen)

pollution
(lichens cannot survive with a high concentration of sulphur dioxide, an air pollutant, and higher pollution levels in water decreases the amount of oxygen)

soil pH
(some plants need acidic soils while others need alkaline)

trampling

soil mineral content
(many plants need high levels of soil minerals to grow)

wind intensity and direction
(some organisms need sheltered locations where seeds are more likely to germinate)

Question 13

pollutant

Answer 13

energy or a chemical substance that has a harmful effect on living organisms

Question 14

give examples of ways changes in non-living factors can be measured

Answer 14

oxygen meter

thermometer

rainfall gauge

Question 15

Nettle plants grow taller when they are under a large tree compared with those growing in open ground

Suggest a reason for this difference [2]

Answer 15

under the tree, the light intensity is lower

therefore the plant grows taller so it has more leaves to trap available light

Question 16

The pygmy shrew weighs only 2.3 to 5g and its length is only 40-55 mm.

It can only live in southern Britain because the rest of the country is too cold. Explain why the pygmy shrew cannot survive in cold places. [2]

Answer 16

large surface area to volume ratio, so it loses heat rapidly

(causing it to need higher temperatures to avoid a decrease in internal temperatures, which could cause harm)

Question 17

producer

Answer 17

producers are plants and algae, which photosynthesise

Question 18

primary consumer

Answer 18

herbivores which eat producers

Question 19

secondary consumer

Answer 19

carnivores which eat primary consumers

Question 20

tertiary consumer

Answer 20

carnivores that eat secondary consumers

Question 21

abundance

Answer 21

number of organisms in an ecosystem