Ecosystems 1

Question 1

What is ecology?

Answer 1

The study of interactions between organisms and their environment

Question 2

What is a producer?

Answer 2

An organism that makes its own energy and biomass using sunlight

Question 3

What is a habitat?

Answer 3

An area which a population of organisms lives in

Question 4

What is a niche?

Answer 4

The part of a habitat which an organism is best suited to

Question 5

What is an environment?

Answer 5

All the conditions that surround a living organism

Question 6

What is a consumer?

Answer 6

Organism which gets its biomass from producers or other consumers by eating them

Question 7

What is a community?

Answer 7

All the living organisms in a habitat

Question 8

What is a trophic level?

Answer 8

The level at which an organism feeds in a food chain

Question 9

What is a detritivore?

Answer 9

An organism which consumes dead or decaying matter

Question 10

What is a decomposer?

Answer 10

An organism which breaks down organic matter

Question 11

What is an autotroph?

Answer 11

An organism which produces its own biomass

Question 12

What is an abiotic factor?

Answer 12

A non-living factor which affects organisms

Question 13

What is a biotic factor?

Answer 13

A living factor which affects organisms

Question 14

What are heterotrophs?

Answer 14

Organisms which get their biomass by consuming organisms from other trophic levels

Question 15

What is a population?

Answer 15

All the organisms of one species living in a habitat at one time

Question 16

What is a microhabitat?

Answer 16

A small part of a habitat with specific conditions

Question 17

What is an ecosystem?

Answer 17

All living and non-living organisms in a habitat and their interactions

Question 18

Can abiotic and biotic factors affect each other?

Answer 18

Yes- each can affect the other

Question 19

What is not recycled within an ecosystem and why?

Answer 19

Energy, as it flows through the ecosystem

Question 20

Are all ecosystems the same size?

Answer 20

No- they can be as small as a bacterial colony or be the whole Earth

Question 21

What are 5 examples of abiotic factors?

Answer 21

1. Light 2. Water availability 3. Soil type 4. Oxygen availability 5. Temperature

Question 22

What type of biomass is used in a pyramid of biomass and why?

Answer 22

Dry mass as fresh mass is unreliable and varies

Question 23

A pyramid of biomass is always what shape?

Answer 23

A pyramid

Question 24

How do you calculate ecological efficiency?

Answer 24

(Biomass of primary consumer/Biomass of producer) x 100

Question 25

What is productivity?

Answer 25

The rate at which energy passes through each trophic level

Question 26

What is gross primary productivity?

Answer 26

The rate at which plants convert light energy to chemical energy

Question 27

How do you calculate net production?

Answer 27

Net production = Gross production - Respiratory losses

Question 28

What is net production?

Answer 28

The amount of organic matter remaining after respiration

Question 29

What are 7 ways of increasing net production?

Answer 29

1. Increase light availability 2. Ensure ideal temperature 3. Use insecticides 4. Use fungicides 5. Ensure maximum nutrient availability 6. Use herbicides 7. Use irrigation/drought resistant strains

Question 30

What is biomass?

Answer 30

The amount of living material present in a particular place or within organisms

Question 31

What units is biomass measured in?

Answer 31

Grams per metre squared (on land) or per metre cubed (in water)

Question 32

What is ecological efficiency?

Answer 32

The efficiency at which biomass or energy is transferred between one trophic level and the next

Question 33

What is nearly always true about biomass and trophic levels?

Answer 33

Increasing trophic levels generally see a decrease in biomass

Question 34

What are 4 reasons consumers do not convert all the biomass from their food into their own organic tissue?

Answer 34

1. Not all biomass of an organism is eaten (i.e. bones) 2. Some energy transferred to environment as metabolic heat due to movement and respiration 3. Some energy lost via excretory materials 4. Some parts of an organism eaten but indigestible

Question 35

What are 4 ways humans can manipulate biomass transfer in agriculture?

Answer 35

1. Create very simple food chains 2. Keep abiotic factors ideal 3. Minimise interspecific competition 4. Remove threat of predators

Question 36

What 2 things are the most common decomposers?

Answer 36

Microscopic fungi and bacteria

Question 37

What methods are used to measure distribution of species?

Answer 37

Line or belt transect

Question 38

What type of sampling are line and belt transects?

Answer 38

Systematic

Question 39

How do organisms tend to be distributed within a habitat?

Answer 39

Where biotic and abiotic factors favour them

Question 40

Given that transects cannot be used on animals, what method tends to be used to measure their abundance?

Answer 40

Capture-mark-capture-release

Question 41

What method is used to numerically measure biodiversity?

Answer 41

Simpson's Index of Diversity

Question 42

What are the 6 steps of capture-mark-capture-release?

Answer 42

1. Capture as many individuals as possible in a sample area 2. Mark or tag each individual 3. Release marked animals and give them time to reintegrate into the environment 4. Recapture as many as possible in sample area 5. Record number of marked and unmarked animals in sample 6. Use Lincoln index to measure population size