5. On the Wild Side (1)

Question 1

Habitat

Answer 1

Where an organism lives

Question 2

Population

Answer 2

All the individuals of one species living in a habitat

Question 3

Size of population = …?

Answer 3

abundance of a species in a habitat

Question 4

Exact location of a population =…?

Answer 4

Species distribution

Question 5

Ecosystem

Answer 5

a community and its interactions with the non-living parts of its habitat

Question 6

Community

Answer 6

multiple populations living and interacting in the same area

Question 7

Biotic factors

Answer 7

Predation

Food availability

Intraspecific competition

Interspecific competition

Cooperation between organisms

Parasitism

Disease

Question 8

intraspecific competition

Answer 8

arising when individuals of the same species compete for resources

Question 9

Interspecific competition

Answer 9

arising when individuals of different species compete for resources

Question 10

Availability of food effects?

Answer 10

• organisms have a higher chance of surviving and reproducing
• their populations can increase

Question 11

New predators effects?

Answer 11

balanced ecosystems - predators catch enough prey to survive, but not so many they wipe out the prey population.

New predators introduced to the ecosystem, ecosystem becomes unbalanced

Question 12

New pathogens effects

Answer 12

New pathogens entering = populations will have no immunity or resistance to it and the population may decline.

Question 13

Competition effects

Answer 13

Better adapted species will outcompete ither species until there are too few members of the lesser adapted species to breed successfully

Question 14

Abiotic factors

Answer 14

Light intensity and wavelength

Temperature

Turbidity, or cloudiness, of water

Humidity

Soil or water pH

Soil or water salinity

Soil composition

Oxygen or Carbon dioxide concentration

Question 15

Light intensity

Answer 15

Light needed by plants for photosynthesis - more light = increased plant growth rate

Question 16

Temperature

Answer 16

affects rate of photosynthesis in plants

Question 17

Wind intensity and direction

Answer 17

• wind speed affects transpiration rate in plants
  Transpiration affects the rate of photosynthesis

Question 18

soil ph/ mineral conc/ water levels

Answer 18

certain animals adapted to certain conditions

Question 19

Niche

Answer 19

Role of a species within its habitat

Question 20

Two species in one niche? =

Answer 20

competition

Question 21

Hoe does the niche filled by a species determine its abundance within a habitat

Answer 21

abundance = number of individuals of a particular species living in a habitat

2 species in one niche = competition = populations are smaller and therefore abundance will be lower

Question 22

How do niches influence distribution

Answer 22

Species can only survive in habitats where they are well adapted -
not being well adapted = they move to a more suitable habitat and distribution changes

Question 23

Fist stage of succession

Answer 23

Primary succession - seeds and spores that are carried by wind land on rock and begin to grow

These are known as pioneer species - i.e. mosses and lichens.
Lichens slowly break apart the top surface of bare rock - forming a basic soil

Pioneer species germinate easily and withstand harsh conditions

Question 24

Second stage of succession

Answer 24

pioneer species die and decompose - dead organic matter forms thin soil - humus.
Plants are adapted to survive in the shallow nutrient poor soils.

Roots of these small plants stabilise the soil. These small plants die and decompose and the soil becomes deeper and more nutrient rich

Larger plants, shrubs, and small trees begin to grow - these require more water which can be stored in deeper soils

Question 25

Third stage of succession

Answer 25

soil becomes sufficiently deep, supports large trees. Final species colonise the newly formed land and outcompete previous species (including the pioneer species) Stable, final community form which is known as the climax community

Question 26

How can newly exposed land form?

Answer 26

Landslide exposing bare rock, or a glacier retreating

Question 27

Secondary succession

Answer 27

Previous communities destroyed (i.e. by a wildfire or deforestation.) succession occurs against but the difference is that the soil is already present so the process begins at a later stage.

Question 28

Pagioclimax

Answer 28

Human activities preventing/ interrupting the process of succession - preventing a climax community from developing

Question 29

some causes of pagioclimax

Answer 29

Regular mowing and grazing activity

Question 30

Producers

Answer 30

plants that convert light energy into chemical energy

Question 31

primary productivity

Answer 31

rate at which producers convert light energy into chemical energy

Question 32

Gross primary productivity (GPP)

Answer 32

rate at which chemical energy is converted into carbohydrates during photosynthesis

Question 33

Net Primary Productivity (NPP)

Answer 33

NPP = GPP - R (respiration losses which isn't stored as new plant biomass and won't be passed onto herbivores aka primary consumers.)

Question 34

NPP Definition

Answer 34

rate at which energy is stored in plant biomass

Question 35

what does NPP show?

Answer 35

The energy available to organisms at higher trophic levels in the ecosystems - primary consumers and decomposers

Question 36

NPP units - energy and area

Answer 36

Using area: J m–2 yr-1 (joules per square metre per year)

Question 37

NPP units - volume and time

Answer 37

Using volume: J m–3 yr-1 (joules per cubic metre per year) used when calculating NPP in aquatic habitats

Question 38

Primary Consumers

Answer 38

Animals that eat plant material- herbivores/ omnivores

Question 39

What is chemical energy used for

Answer 39

Chemical energy is used to fuel respiration but also builds up biomass in the tissues when ingested

Question 40

What happens when an organism dies?

Answer 40

Chemical energy stored in its tissues passes to decomposers

Question 41

Trophic level 1

Answer 41

Producer

Question 42

Trophic level 2

Answer 42

Primary Consumer

Question 43

Trophic Level 3

Answer 43

Secondary Consumer

Question 44

Trophic level 4

Answer 44

Tertiary Consumer

Question 45

Trophic level 5

Answer 45

Quaternary Consumer

Question 46

Arrows in a food chain represent what?

Answer 46

Transfer of energy between trophic levels

Question 47

Why are food chains never 100% efficient?

Answer 47

Energy is lost to the environment at every trophic level

Question 48

How is light not available to producers for building biomass

Answer 48

- light passes through the leaves or is reflected away - light hits the non-photosynthetic part of the plant - only certain wavelengths are absorbed in photosynthesis and light is a mixture of wavelengths -Energy released during photosynthesis, some is lost to the environment in the form of heat

Question 49

Why is 90% of energy lost to the environment

Answer 49

- Not every part of the food organism is eaten - consumers are unable to digest all the food they ingest like cellulose or fur so it gets egested as poop - respiration causes energy loss - heat is lost to the environment - excretion - urea in urine, sweat etc.

Question 50

net productivity

Answer 50

rate at which energy is converted into biomass in the body of a consumer

Question 51

Percentage of energy available to organism at next level vs wasted

Answer 51

10 available/ 90 wasted

Question 52

Energy efficiency equation

Answer 52

Energy efficiency = (net productivity/ energy received) x 100 * can also be calculated by subtracting energy losses from energy received *

Question 53

How is biomass calculated

Answer 53

Dry biomass - drying a sample of the organism in an oven at low heat and weighing the sample at regular intervals until the mass becomes constant The organism must be dead for this process to be carried out

Question 54

Why is dry biomass used

Answer 54

the amount of water stored in tissues can vary

Question 55

efficiency of biomass transfer percentage equation

Answer 55

EoB = (biomass transferred/ biomass intake) x100 biomass transferred - biomass passed onto higher trophic level biomass intake - biomass of the lower trophic level that has been consumed