Ecosystems

Question 1

Define Ecosystem

Answer 1

A community of plants and animals that interact with each other and their physical environment

Question 2

Define Biome

Answer 2

a very large ecosystem found on a regional scale e.g tropical rainforests
They are characterized by similar flora fauna and climates.

Question 3

Define nutrient cycling

Answer 3

A set of processes whereby organisms extract minerals necessary for growth from soil or water before passing them on to the food chain and ultimately back to soil + water

Question 4

Biotic factors (living)

Answer 4

Bacteria, Plankton, Fungi, Insects, Predation, Human activity, Disease, Mammals

Question 5

Abiotic Factors (non-living)

Answer 5

Sunlight, soil pH, soil moisture, heat, shade

Question 6

Define micro-habitat

Answer 6

A very small scale system where organisms interact within their environment e.g a tree or your intestines

Question 7

Outline differences between foodchain and food web

Answer 7

Food chain -> linear flow of nutrients, from organism to organism, only one organism from each trophic level

Food Webb -> multitude of interconnected food chains with lots of organisms from the same trophic levels, more accurately shows food chains in ecosystem

Question 7

Define Biosphere

Answer 7

all living organisms in the world and their physical environment

Question 8

small scale ecosystem example

Answer 8

Reigate Heath, Surrey

Question 9

what is an interrelationship

Answer 9

a species dependency on another in their environment

Question 10

Reigate Heath secondary consumers

Answer 10

Birds e.g Dartford Warbler feeds on insects
Small mammals e.g weasel preys on rabbits and rodents

Question 10

Reigate Heath producers

Answer 10

Heather (thrives in acidic nutrient poor soil + provides food for many species)
Gorse (key shrub offering shelter + food for insects and birds)

Question 11

Reigate Heath primary consumers

Answer 11

Rabbits, various insect species e.g butterfly silver-studded Blue

Question 12

Reigate heath tertiary consumer

Answer 12

Bird e.g Kestrel hunting small mammals

Question 13

Reigate Heath Decomposers

Answer 13

Fungi (various species decompose leaf litter and dead wood, releasing nutrients back into soil)
Bacteria (facilitating nutrient recycling)
Detritivores (insects such as beetles and worms that feed on decomposing plant/animal material)

Question 14

what nutrients are released into soil by decomposition

Answer 14

nitrogen and phosphorous

Question 15

How does human activity affect Reigate Heath ecosystem

Answer 15

Golf course = humans trample ground = becomes uneven/infertile
Car Park = car fumes cause air pollution
Pond/lakes become littered
News roads/houses built ruin habitats for insects and animals

Question 16

2 main sources of nutrients in ecosystem

Answer 16

• rainwater washes chemicals out of atmosphere
• weathered rock releases nutrients in soil

Question 17

what 2 things make up nutrient cycle

Answer 17

stores and flows

Question 18

What is the nutrient cycle

Answer 18

Nutrient stores fallout of dying tissue in biomass (living organisms e.g plants/animals)
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Dead plant/animals material on forest floor (litter) is decomposed and releases nutrients into soil
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Soil becomes fertile causing rapid vegetation growth as they are up taken by plants

Question 19

why does soil profile vary biome to biome

Answer 19

they reflect the climate, vegetation, and biome in which they are found in

Question 20

explain the balance of components in ecosystem

Answer 20

If there is change in one component = knock on effects for whole web e.g reduction of food available for larger consumers = overconsumption of other food resources.

Question 21

what are biomes

Answer 21

areas classified according to the species that live in that location

Question 22

factors that influence the distribution of biomes

Answer 22

temperature range, soil type, amount of sunlight

Question 23

Describe the Biome of Coniferous forests

Answer 23

Roughly 60 degrees north
Cold, dark winters, quick hot summers, many are green so they can photosynthesise after winter
Large areas in North America, Europe and Asia

Question 24

Describe the Biome of Deciduous forests

Answer 24

Roughly 50 degrees north= natural ecosystem of UK/much of western europe
Shed their leaves in winter to retain moisture - climate is moderate/mostly mild/most condition - a few extreme temps
Found in both hemispheres

Question 25

Describe the Biome of Mediterranean

Answer 25

Roughly 40-50 degrees north equator
Hot dry summers, wet/mild winters, citrus fruit vegetation, oaks, olives e.g Greece/Spain

Question 26

Describe the Biome of Polar/Tundra

Answer 26

Arctic/Antarctic at high latitudes
Extremely cold throughout year, cold winters, brief warm summers in tundra regions, limited precipitation
Tundra region fragile/easily damaged by human activities

Question 27

Describe the Biome of Savannah

Answer 27

15-30 degrees north/south equator- distinct wet/dry seasons, fires common in dry seasons but ignited by lightning strikes, lions