Module 4: Ecosystem Dynamics

Question 1

Abiotic definition

Answer 1

physical rather than biological; not derived from living organisms.

Question 2

biotic definition

Answer 2

relating to or resulting from living organisms

Question 3

abiotic examples

Answer 3

• Light
• Temperature
• Water
• Shelter
• Topography
• Chemical components

Question 4

biotic examples

Answer 4

plants, animals, algae, funghi

Question 5

How do abiotic factors affect species?

Answer 5

Biotic factors in environment that affect a species. Influence behaviour, survival and reproduction. Organisms have certain characteristics suited for different environments -survival benefits.
Organisms less suitable for specific conditions are less likely to reproduce.

Question 6

abiotic complex example:

Answer 6

Coral bleaching
Selection pressures: rise in sea temperature
Effect: bleached coral will die, reducing size of reef for marine.

Question 7

Selection pressure

Answer 7

Selection pressure means factors that contribute to selection which variations will provide the individual with an increase chance of surviving over others.

Question 8

effect of selection pressure:

Answer 8

Because of selective pressures, organisms with certain phenotypes have an advantage when it comes to survival and reproduction.

Question 9

Keystone selection pressure:

Answer 9

when keystone spec is removed, ecosystem becomes less stable and structure changes.

Question 10

Keystone selection pressure effect:

Answer 10

Consequences on diversity and abundance.

Question 11

Acidification:

Answer 11

Selection pressure: Water pH
Individual effect: Affects the deposition of calcium carbonate
Possible consequence: Reduces the habitat for the algae and therefore less food for the polys

Question 12

Crown of Thorns Starfish

Answer 12

Selection pressure: Predators
Individual effect: Affects the population of the coral Possible consequence:Reduces the amount of habitat left for the marine life as more coral is dying.

Question 13

Climate change

Answer 13

Selection pressure: Water temperature
Individual effect: Not ideal temperatures for breeding Possible consequence: Extinction of certain animals that cannot live in warmer temperatures

Question 14

Tourism

Answer 14

Selection pressure: Stress on the environment Individual effect: Broken coral, fuel in the water and disruption to the usual functioning of the ecosystem Possible consequence:Damage to the natural habitat

Question 15

Symbiosis

Answer 15

living together

Question 16

What are the two types of relationships between different species?

Answer 16

Beneficial and detrimential

Question 17

mutualism example

Answer 17

1. Mutualism - sea anemone (provides shelter and protection) and clown fish (provides nutrients)

Question 18

commensalism example

Answer 18

2. Commensalism - shark (no benefit), and remora (small fish feed on scraps of prey of sharks)

Question 19

parasitism example

Answer 19

3. Parasitism - head lice (feed on blood) and human (host)

Question 20

mutualism

Answer 20

both organisms benefit

Question 21

commensalism

Answer 21

one benefits, the other unharmed

Question 22

predation

Answer 22

one organism eats another

Question 23

predation example

Answer 23

dingo eats wallaby

Question 24

parasitism

Answer 24

one organism lives on another obtaining food from it

Question 25

competition

Answer 25

organism compete for limited resources

Question 26

example of competition

Answer 26

insects for nectar

Question 27

inhibition

Answer 27

one organism directly prevents the development of a competing organism

Question 28

Consequences of predation:

Answer 28

• Predator numbers copy those of prey

Question 29

Consequences of competition:

Answer 29

• If one species is more successful, then the less successful species may be driven to very low numbers or die out completely

Question 30

Effects of symbiosis:

Answer 30

* Increased evolutionary diversification e.g. biodiversity * Development of new species e.g. integration of genetic material and development of eukaryotic cells * Sources of new capabilities e.g. enhancement in evolutionary fitness

Question 31

Consequence of predation

Answer 31

Animal species kills and feeds on another, predator eats prey. high prey compared to lower predators means that predators increase and prey decreases (because they are all eaten), causes shortage of food as the prey has all been eaten meaning that predators decrease too.

Question 32

individual relationship

Answer 32

single organisms

Question 33

population relationship

Answer 33

group of organisms, same species

Question 34

communities relationship

Answer 34

ecological grouping of different species living and interacting together.

Question 35

ecosystems relationship

Answer 35

formed by communities interacting with one another and physical surroundings.

Question 36

biomes relationship

Answer 36

group of communities with similar structures and habitats extended over a large area.

Question 37

biospheres relationships

Answer 37

sum of all ecosystems on earth.

Question 38

habitats

Answer 38

where an organism lives.

Question 39

microhabitats

Answer 39

smaller area within habitat (tree canopy) where organisms experiences different environments compared to overall habitat (temp, humidity, sunlight)

Question 40

Niches

Answer 40

the specific way in which an organism fits into its community or ecosystem, including its actual habitat, use of resources and its abiotic and biotic interactions.

Question 41

Intraspecific competition

Answer 41

between species

Question 42

interspecific competition

Answer 42

within a species

Question 43

How do you measure population through sampling techniques?

Answer 43

quadrants, transects, tagging and capture-recapture

Question 44

quadrants

Answer 44

throw quadrat randomly into an area and count the population of a certain species. Used for counting small plants or slow moving, small animals.

Question 45

transects

Answer 45

to determine variation within the population. Used to count larger plants.

Question 46

Tagging/capture-recapture:

Answer 46

to recognise the animals that have already been counted. Use to count animals that move and are hard to identify.

Question 47

What are adaptations?

Answer 47

characteristics that increase the survival and reproductive chances of an organism in its environment. They are not a change that an organism makes in response to the environment but usually begin as variations.

Question 48

structural adaptations

Answer 48

things you can see, body shape, anatomical features that assists an organism to adapt to abiotic or biotic environment e.g. large ears, sunken stomata, flying fish body shape

Question 49

behavioural adaptation

Answer 49

actions that an organism takes to improve survival e.g. seeking shade or shelter, migration

Question 50

Physiological adaptation:

Answer 50

inner body functions e.g. production of concentrated urine, venom, shivering to maintain body temperature, antifreeze in arctic plants

Question 51

Paleontology -

Answer 51

the scientific study of fossils and all aspects of extinct life

Question 52

geology

Answer 52

the scientific study of the origin, history and structure of the Earth as recorded in rocks

Question 53

Fossils:

Answer 53

* Law of superposition, fossils in different layers relate to age * Darwin’s Theory of Evolution by natural selection

Question 54

Aboriginal rock art:

Answer 54

* Depicts flora and fauna of the past | * e.g. thylacine, droughts

Question 55

Geological evidence:

Answer 55

* Changes from anaerobic to aerobic atmosphere | * Shown in banded iron

Question 56

Microfossils

Answer 56

* Earlier fossils | * e.g. single celled, filamentous anaerobic prokaryotes (didn’t have a nucleus, and didn’t require oxygen)

Question 57

Why do scientists continue to make theories?

Answer 57

Scientists continue to develop theories about how life has changed on Earth. Changes in abiotic and biotic factors have left traces of evidence behind. Scientists study this evidence, make inferences and reconstruct past ecosystems.

Question 58

What is a niche comprised of?

Answer 58

 The habitat in which an organism lives  The activity patterns of the organism (e.g. periods of time during which it is active)  The resources it obtains from the environment (e.g. food sources, territorial boundaries, etc.)  The interactions that occur with other species in the community (e.g. predator prey relationships, competition, etc.)

Question 59

Understanding: Niches and species

Answer 59

Two species cannot survive indefinitely in the same habitat if their niches are identical If two distinct species share an identical niche, there will be interspecific competition for available space and resources

Question 60

competitive exclusion

Answer 60

one species uses resources more efficiently and drives out another species to extinction

Question 61

resource partitioning

Answer 61

species alter their use of niche and divide resources