Ecology

Question 1

What is an ecosystem?

Answer 1

All communities,organisms, factors (abiotic and biotic) in a particular area.
Factors can be interacting or interdependent
Self contained system - self supporting energy flow
Eg. Coral reef- marine ecosystem

Question 2

What is habitat?

Answer 2

Geographical area occupied by ecosystem.
Subdivided -layers/zones
Micro habitats- forest canopy= leaves/ branches

Question 3

What is the environment ?

Answer 3

All factors in a habitat that affect an organism.
Biotic factors- living
Abiotic - non living

Question 4

What is population?

Answer 4

All members of 1 species in a habitat at one time eg. Number of people living in belfast
Calculation- BR/ Imigration- DR/emigr = pop. growth

Question 5

What is community?

Answer 5

All organisms in one habitat at at one time (plants and animals- biotic factors)

Question 6

What is species?

Answer 6

Group of potentially interbreeding animals which do not normally interbreed with other groups/ species to produce viable fertile offspring

Question 7

What is classification and it’s use?

Answer 7

Arrange organisms into specific groups depending on characteristics.
Identify new species or unfamiliar ones.
Uses: identification, study how species change, compare biodiversity, and for conservation

Question 8

What’s a key stone species?

Answer 8

Species in a community with a vital role- without them the ecosystem can collapse

Question 9

What is niche?

Answer 9

Role of species in an ecosystem
Location, spacial habitat, function, relationships with organisms and environment
“ competitive exclusion rule” don’t want to compete
Eg. Red and grey squirrels

Question 10

What are environmental factors that affect an ecosystem?

Answer 10

Abiotic ( non living) climate, physiography,soil

Biotic ( living) plants, animals, microbes

Question 11

What abiotic factors affect an ecosystem ?

Answer 11

Fires, hurricane, tsunami, volcanos, global patterns of circulation ( rainfall, wind El Niño, ocean currents)

Question 12

List the 2 abiotic components?

Answer 12

Inorganic- sulphur, boran - cycle through

Organic- proteins, lipids , carbohydrate - link biotic and abiotic

Question 13

List the abiotic factors that affect an ecosystem?

Answer 13

Wind, rain, humidity, pH, light, temp

Question 14

How can we measure biotic factors?

Answer 14

Greater no. Plants and animals - greater biodiversity

Distribution of animals depends on: food, mates, territories, adaption of an animal eg.camel to desert

Question 15

What is the main biotic factor?

Answer 15

Competition
Habitats- limited resources- must compete with others for these- if unsuccessful and can’t move to another habitat they will DIE
“Survival of the fittest”

Question 16

What do plants and animal compete for?

Answer 16

Plants- light, water, space, mineral salts

Animals- food, water, space, mates

Question 17

What are the biotic components of an ecosystem?

Answer 17

Classified by mode of energy acquisition.
Producers- autotrophs- source of all food by photosynthesis
Consumers- heterotrophs- aerobic/anaerobic respiration
Decomposers- matter recycles- release organic components into soil- used by producers

Question 18

What are tropic levels?

Answer 18

Rank in feeding order

1. Producers
2. Consumers
3. Detritvores and decomposers

Question 19

What’s the difference between matter and energy?

Answer 19

Neither can be created or destroyed.
Energy moves through a system in 1 direction ( FLOWS)
Matter cycles between living and non living things ( CYCLES)

Question 20

What is in the first tropic level?

Answer 20

Autotrophs- plants- photosyn- glucose

Chemosynthetic bacteria- geothermal bacteria

Question 21

What make up the 2nd 3rd and 4th tropic level?

Answer 21

Consumers.
Primary-consume producers- herbivores eg. Deer
Secondary- eat primary consumers- carnivores eg. Wolf
Tertiary - eat secondary consumers eg. Hawk
Omnivores- eat plant and animals

Question 22

What is a food chain?

Answer 22

Relationship of how energy is transferred up the trophic levels.
Plants- herbivores- carnivores

Question 23

What is a food web?

Answer 23

Network of interconnecting food chains.

More realistic

Question 24

What happens if an organism is removed from a food web?

Answer 24

Has a major effect on other species

No rabbits, foxes eat more birds, more spiders, less grasshoppers

Question 25

What is a pyramid of numbers, advantages and disadvantages?

Answer 25

Counts the number of species- not always a pyramid
Advantage- simple easy, good for comparison of Eco. Diff times of year
Disad.- no. species to great to measure, not include juvenilles, all organisms included regardless of size ( inverted pyramid)

Question 26

What is pyramid of biomass, advantages and disadvantages?

Answer 26

Dry mass of living material per unit area- more accurate
Advant.- overcomes problems of pyramid of numbers
Disad.- diff to measure biomass exactly, time of year can affect biomass result, organisms of same size not always same energy content

Question 27

What are pyramids of production?

Answer 27

Show flow of energy from producers through trophic levels.
Most of the time only 10% energy is transferred.
Not efficient

Question 28

How is energy lost through the trophic levels?

Answer 28

Heat
Waste
Movement
Respiration
Top of level most dangerous as it has the least amount of energy

Question 29

What happens to poisons and pesticides going up the food chain?

Answer 29

They become more concentrated- predator receives biggest dose

Question 30

What limiting factors affect population size?

Answer 30

Food 
Water
Space 
Shelter
BR+immigration - DR+emigration = pop growth

Question 31

What is ecology?

Answer 31

Study of organism and relationship with environment.

Includes biological, chemical and physical factors