Topic B7 - ECOLOGY

Question 1

Population definition

Answer 1

All the organisms of one species living in a habitat.

Question 2

Community definition

Answer 2

Populations of different species living in a habitat

Question 3

Stable Community

Answer 3

All species and environmental factors are in balance, population sizes are roughly constant

Question 4

Ecosystem

Answer 4

Interaction of a community of organisms and the parts of their environment that are non-living

Question 5

Adaptation

Answer 5

Enables an organism to survive in the conditions of its normal habitat

Question 6

Interdependence

Answer 6

Each species in a community depending upon other species for things, e.g pollination, food, or shelter

Question 7

What does biotic factors mean?

Answer 7

Biotic means living factors

Question 8

What does abiotic factors mean?

Answer 8

Non-living factors

Question 9

What two types of factors can affect organisms in a community?

Answer 9

Both biotic (living) and abiotic (non-living)

Question 10

What factors can affect organisms in a communtiy?

Answer 10

1) light intensity - abiotic
2) wind intenisty and direction - abiotic
3) moisture level - abiotic
4) competition - biotic
5) CO2 level for plants - abiotic
6) New predators - biotic
7) food availability - biotic
8) temperature - abiotic
9) solid pH and mineral content -abiotic
10) new pathogens - biotic
11) O2 level for aquatic animals -abiotic

Question 11

What do organisms conpete for?

Answer 11

Plants:
~ light 
~ space 
~ minerals
~ water 

Animals:
~ food
~ mates
~ territory

Question 12

How can a change in an ecosystem affect the community?

Answer 12

Due to interdependence, change in an ecosystem (e.g. a species being removed) can affect the whole community.

Question 13

What is the order of food chains?

Answer 13

Producer ~> Primary Consumer ~> Secondary Consumer ~> Tertiary Consumer

Question 14

Producer

Answer 14

A plant or alga that makes glucose by photosynthesis. All food chains start with a producer.

Question 15

Primary Consumer

Answer 15

An animal that eats producers and may be eaten by secondary consumers.

Question 16

Secondary Consumers

Answer 16

An animal that eats primary consumers and may be eaten by tertiary consumers.

Question 17

Predator

Answer 17

A consumer that kills and eats other animals (prey)

Question 18

Biomass

Answer 18

The mass of a living material

Question 19

What do arrows represent in food chain?

Answer 19

Energy transfer,

Energy stored in biomass is transferred along food chains and used by other organisms to build biomass.

Question 20

What is a sign of a stable community?

Answer 20

In a stable community the numbers of predators and prey rise and fall in cycles.

Question 21

The Predator-Prey Cycle

Answer 21

~ Prey Population Increases
~ Predator Population Increases
~ Prey Population Decreases
~ Predator Population Decreases

^^^ REPEATS IN CYCLE ^^^

Question 22

Why are Predator-Prey Cycles always out of phase with each other?

Answer 22

Because it takes a while for one population to respond to changed in the other population.

Question 23

Biodiversity

Answer 23

The variety of different species on Earth, or within an ecosystem.

Question 24

High Biodiversity

Answer 24

~ Lots of differnet species

~ Reduced dependence of one species on another for things like food, shelter and the maintenance of the physical
environment

= Stable Ecosystems

Question 25

How does biodiversity and human species link?

Answer 25

For the human species to survive, it is important that a good level of biodiversity is maintained

Question 26

How are materials recycled in ecosystems?

Answer 26

Materials are cycled through the abiotic and biotic parts of an ecosystem.

Materials in environment cycle through to materials in organisms through photosynthesis and absorption from soil.

Materials in organisms cycle to materials in environemnt through waste, death and decay.

Question 27

Why do materials decay?

Answer 27

Materials decay because they’re broken down by microorganisms.
Decay puts minerals like mineral ions back into the soil.

Question 28

The Water Cycle

Answer 28

1) Heat of sun causes two things to happen:
- water to evaporate from sea, lake etc.
- water to transpirate from trees

2) This leads to condensation in clouds
3) The clouds then rain (precipitation) onto mountains and trees and seas. Water will roll fown from mountain into lakes etc.

The cycle then repeats

Question 29

Why is PRECIPITATION (rain) so important?

Answer 29

It provides fresh water for plants and animals on land.

Question 30

The Carbon Cycle

Answer 30

1) Multiple sources cause CO2 to build up in air including:
~ Fossil Fuels Burning
~ Animal Respiration
~ Plant Respiration
~ Plant and Animal Products

2) CO2 in air then enables plants to photynthesise, which then cycles back to respiration and providing food for animals which also increases respiration and plant/animal products.

Question 31

Three Consequences of Global Warming

Answer 31

1) Rising Sea Levels leading to flooding
2) A change in the distribution of some organisms
3) A decrease in biodiversity due to extinction

Question 32

What causes the Earth to heat up?

Answer 32

Increasing levels of greenhouse gases in the atmosphere, such as: carbon dioxide from emissions and methane from cows.

Question 33

Pollution Pathway

Answer 33

1) Increasing human population and standard of living
2) more resources used more quickly and more waste produced
3) more pollution
4) more plants and animals killed, so less BIODIVERSITY

Question 34

Three Ways We Pollute The Environment?

Answer 34

WATER | AIR | LAND

1) Sewage, Fertilisers and Toxic Chemicals (e.g pesticides) from farming and industry get washed into WATER
2) Smoke and acidic gases released into the atmosphere pollutes AIR
3) Toxic chemicals and waste dumped into landfill sites pollute LAND

Question 35

Five Programmes to Protect Ecosystems?

Answer 35

1) Breeding Programmes
2) Habitat Restoration
3) Hedgegrows and Field Margins
4) Government Regulations
5) Recycling