U1T4 - Keywords (2)

Question 1

Photoautotrophs

Answer 1

Producers that make their own food from inorganic molecules, water + carbon dioxide using sunlight as energy source.

Question 2

Chemoautotrophs

Answer 2

Producers that use chemical energy to make own food (bacteria in dark caves, make organic substances using minerals in rock as source of chem energy) e.g. nitrifying bacteria.

Question 3

Autotrophs

Answer 3

Producers which make own food + therefore provide food for all other species in ecosystem directly or indirectly.

Question 4

Heterotrophs

Answer 4

Can’t make own food so rely on other living organisms to provide them with organic molecules. Consumers.

Question 5

Trophic Levels

Answer 5

Feeding Levels. Producers = 1st TL. Primary Consumers + 2nd TL etc. Most ecosystems have 3/4 but aquatic may have 6.

Question 6

Detritus Food Chains

Answer 6

Food chains starting with dead organic matter. Dead plants + animals fed upon by detritivores + decomposers.

Question 7

Food Webs

Answer 7

Pattern of interrelated food chains operating in an ecosystem.

Question 8

Pyramid of Numbers

Answer 8

Bar diagram indicating relative num of organisms in food chain/total num of all organisms at each trophic level in food web.

Question 9

Inverted Ecological Pyramid

Answer 9

Top Heavy Pyramid (of Numbers/Biomass)

Question 10

Pyramid of Biomass

Answer 10

Shows mass of living organisms at each trophic level, per unit area/volume at certain time. Illustrates total biomass at each TL.

Question 11

Biomass

Answer 11

Mass of living material present at given time.

Question 12

Wet/fresh mass

Answer 12

Weighing live organisms as they are.

Question 13

Dry mass

Answer 13

Drying organisms until constant mass achieved, more accurate than wet mass but more time consuming and kills organism.

Question 14

Standing Crop

Answer 14

Num of organisms present at any one time. (with biomass)

Question 15

Pyramid of Energy

Answer 15

Takes into account productivity for each TL in ecosystem during fixed period of time. (1 year takes into account annual changes so units are kJ.m^-2.y^-1.

Question 16

Productivity

Answer 16

How much new material produced.

Question 17

The sun

Answer 17

The ultimate energy source for all ecosystems.

Question 18

Photosynthesis

Answer 18

The route by which energy is made available to the ecosystem.

Question 19

GPP

Answer 19

Gross Primary Production. Energy in organic compounds produced by plants in photosynthesis (units kJm^-2yr^-1 or biomass per metre squared per year). Not all of this is available for next trophic level as some (50%) used in resp.

Question 20

NPP

Answer 20

Net Primary Production. Represents rate of production of new biomass which is available for consumption by heterotrophic organisms. If plants die, NPP in form of dead leaves/flowers forms detritus. GPP - R.

Question 21

Detritus

Answer 21

NPP in form of dead leaves/flowers.

Question 22

Heterotrophic Organisms

Answer 22

Only energy source in ecosystem for next trophic level.

Question 23

Trophic Energy

Answer 23

Percentage of energy at one TL which ends up in next TL.

Question 24

Herbivores

Answer 24

Obtain energy by eating primary producers. Only 5 - 10% of energy gets transferred to them. e.g. deer + pandas

Question 25

Primary Consumers

Answer 25

Feed on producers e.g. aphids + rabbits

Question 26

Secondary Consumers

Answer 26

Feed on primary consumers e.g. ladybugs + skunks

Question 27

Tertiary Consumers

Answer 27

Feed on secondary consumers e.g. owls + humans

Question 28

Carnivores

Answer 28

Organisms which feed on other animals e.g. hyenas + whales

Question 29

Detritivores

Answer 29

Organisms involved in decay + decomposition. Feeds on dead organic material. e.g. sea cucumbers + dung beetles

Question 30

Decomposers

Answer 30

Organisms involved in decay + decomposition. Decomposes dead organic material. e.g. snails + mushrooms

Question 31

Grazing Food Chain

Answer 31

Starts from the autotrophs (green plants), energy is taken from the sunlight as green plants prepare food in the presence of it.

Question 32

Omnivore

Answer 32

An animal that eats both plants and animals.

Question 33

Producer

Answer 33

Organisms that make organic substances from inorganic substances using energy. Almost all use light energy to do this. Some use chemicals (chemoautotrophs)

Question 34

Consumer

Answer 34

Organisms that obtain energy by feeding on other organisms.

Question 35

Energy Transfer Inefficiency

Answer 35

When energy is transferred by an appliance the energy is converted from one form to another. Some of the energy will be usefully transferred by the device and some will be wasted.

Question 36

Endotherms

Answer 36

An animal dependent on/capable of internal heat generation.

Question 37

Fertilisers

Answer 37

Chemical/natural substance added to soil/land to increase fertility.

Question 38

Pesticides

Answer 38

Substance used for destroying insects or other organisms harmful to cultivated plants or to animals.

Question 39

Energy Budget

Answer 39

An energy budget is a balance sheet of energy income against expenditure. P= C - (R + U + F)

Question 40

Net Secondary Productivity

Answer 40

The biomass gained by heterotrophic organisms, through feeding and absorption, measured in units of mass or energy per unit area per unit time (minus what is lost)

Question 41

Food Chain

Answer 41

Shows link between producer, primary consumer, secondary consumer + potentially tertiary consumer. Not v.realistic.

Question 42

Silage

Answer 42

Cut grass/maize chopped into small pieces + stored in anaerobic conditions (covered in plastic). It creates lactic acid, low pH stopping other decomposing microbial growth preserving high nutrient status. Partial decomp.

Question 43

Secondary Productivity

Answer 43

Productivity in animals. Energy used in production of new tissue in animals. Worked out using energy budgets.