Mod 3 + 4 (Term 1 Exam)

Question 1

Ecosystem

Answer 1

An ecosystem is made up of organisms (biotic) living in an area that interact with each other
and with the non-living (abiotic) environment in which they live.

the combination of all the organisms (biotic factors) living in a community (a group of different populations in an area or habitat) and all the non-living features (abiotic factors) with which they interact.

community + env: environment containing organisms interacting with each other and the non-living parts of the env

Question 2

MOD 3 -> investigate and determine relationships between biotic and abiotic factors in an ecosystem,
including:
-> the impact of biotic factors

Biotic Factors

Answer 2

any living factor that affects another organism, or shapes the ecosystem in some way

Living components of the ecosystem that affect organisms (organisms -> plants, animals, bacteria - disease)

Question 3

MOD 3 -> investigate and determine relationships between biotic and abiotic factors in an ecosystem,
including:
-> the impact of abiotic factors

Abiotic Factors

Answer 3

Non-living features of the environment that can affect organisms (physical and chemical) + survival

Question 4

Environment

Answer 4

Within an ecosystem, the environment is made up of all the non-living (abiotic) factors.

Question 5

ephemeral

Answer 5

lasting for a very short time - e.g. ephemeral plants -> a plant with a very short life cycle or very short period of active growth, often one that grows only during brief periods when conditions are favorable (Plants growing in desert complete their life cycle within the rainy period that lasts for few weeks)

Question 6

MOD 3 -> investigate and determine relationships between biotic and abiotic factors in an ecosystem,
including:
-> the impact of abiotic factors

Abiotic factors examples

Answer 6

-> chemical (e.g. pH mineral content of soil) or physical (e.g. temp of air) part of the environment
-> light intensity, co2 concentration, oxygen concentration, temperature, wind intensity and direction, moisture level
-> increase in temp could increase rate of photosynthesis - enzymes can work faster - increase plant growth rate
-> animals spend less energy staying warm - energy for growth (less time searching for food)

physical + chemical

temperature, light intensity, water,

sunlight, air, humidity, pH, temperature, salinity, precipitation, altitude, type of soil, minerals, wind (direction and intensity), dissolved oxygen, mineral nutrients present in the soil, co2 concentration, oxygen concentration, moisture level, etc

Question 7

MOD 3 -> investigate and determine relationships between biotic and abiotic factors in an ecosystem,
including:
-> the impact of biotic factors

Biotic factors examples

Answer 7

(e.g. predation - a living process that influences the population of another species) (e.g. competition for resources or habitat) (e.g. amount of disease) (e.g. availability of food)
-> just think of all the ways living organisms (animals, plants, bacteria, viruses) can affect one another

predation, habitat, amount of disease, availability of food, plants, animals, producers, consumers, herbivores, carnivores, and omnivores, competition, parasitism

availability and abundance of foods
number of competitors
number of mates
number of predators
number and variety of disease-causing organisms.

Question 8

Community

Answer 8

group of different populations in an area of habitat

Question 9

Population

Answer 9

group of organisms of the same species living in the same area at a particular time

Question 10

Abiotic factors in aquatic environments (types)

Answer 10

SALT CONCENTRATIONS, light availability, pressure

salt water/marine, fresh water or estuarine (exposed to both fresh water and salt water)

The main types of organisms found in aquatic environments are influenced by the level of water salinity.

Question 11

biotic and abiotic factors relationship

Answer 11

Biotic features of ecosystems vary widely in response to the abiotic features of the environment.

Question 12

factors effect on organisms

Answer 12

Abiotic and biotic factors act on the characteristics of the organisms and affect the ability of an
organism to survive and reproduce in a particular environment.

a change will lead to migration or extinction

Question 13

Abiotic factors create selection
pressures affecting biotic factors

Answer 13

Abiotic factors select for different types of organisms and hence affect biotic factors. The underlying
abiotic factors of an ecosystem therefore must be studied in order to determine the possible effect that
they may have on the biotic components of that ecosystem.

An organism’s ecosystem provides it with nutrients, water, shelter and opportunities to mate. Other
living things compete with it for these resources. This competition results in some organisms being able
to survive and reproduce, while others are unable to compete successfully for resources. As a result,
individuals in the successful species will have a range of favourable characteristics (adaptations) uniquely
suited to the specific set of environmental factors in their habitat. The population is said to be adapted
to this habitat. Unless the environment changes, the species will continue to survive, reproduce and pass
on these characteristics to their offspring.

Question 14

selection pressures.

Answer 14

natural selection - affects the behaviour, survival, and reproduction of an Organism

a change in environment often results in some resources becoming limited, and individuals have
to compete for these limited resources

Question 15

abiotic factors - selection pressures

Answer 15

temperature, light intensity, soil type, water
availability and gas concentration in water,

Question 16

biotic factors - selection pressures

Answer 16

competition between members
of a species for the same limited resources, predators and availability of prey

Question 17

Distribution

Answer 17

where a species is found

affected by ab + b factors

Question 18

Abundance

Answer 18

how many individuals of that species live throughout the ecosystem

affected by ab + b factors

Question 19

Ecology

Answer 19

the study of interrelationships between different types of organisms and between organisms
and their environment. -> determines the distribution and abundance of flora and
fauna

Question 20

questions ecologists need to answer when studying biodiversity:

Answer 20

1. Why is a species only present in particular places?
2. What determines the number of individuals (size) of a population in one particular place?

-> This information enables them to
determine whether a population is increasing or decreasing in size and what particular aspects of the
habitat are favoured over others.

i.e. what factors influence the distribution and abundance of populations in particular
environments? If the distribution and abundance of flora and fauna in a particular ecosystem changed
due to climate or development, what would be the associated biodiversity risks?

Question 21

biotic + abiotic + selection

Answer 21

Biotic and abiotic factors exert selection pressures that influence the survival and reproduction
of an individual, population or species.

Question 22

b + ab selection pressures effect

Answer 22

Biotic and abiotic selection pressures affect the distribution and abundance of organisms in an
ecosystem.

Question 23

main influences on abund + dist in australia

Answer 23

Rainfall, temperature and landform patterns significantly affect the abundance and distribution
of organisms in ecosystems in Australia

Question 24

what do ecologists study?

Answer 24

Ecologists study the distribution and abundance of organisms and how these properties are
affected by interactions between the organisms and their environment.

Question 25

Sampling techniques

Answer 25

used to calculate the abundance of organisms. These techniques include the use of quadrats to estimate percentage cover for plant species and the mark–
release–recapture technique for animal species.

Question 26

MOD 3 -> predict the effects of selection pressures on organisms in ecosystems, including: – biotic factors

Biotic factors???

Answer 26

When a variety of species is present in the ecosystem, the actions of these species can affect the lives of other species in the area; these factors are biotic factors. Biotic factors are the livign factors that affect an organism

Question 27

MOD 3 -> predict the effects of selection pressures on organisms in ecosystems, including: – abiotic factors

Abiotic factors???

Answer 27

Organisms that live in an environment rely on favourable conditions in the area to allow them to successfully live and reproduce. These enviromeentla conditions are called abiotic factors.Abitioci factors are the non-living factors that affect an organism.

Question 28

MOD 4 -> * investigate and determine relationships between biotic and abiotic factors in an ecosystem, including: – measuring populations of organisms using sampling techniques

What is distribution? What is abundance?

Answer 28

The DISTRIBUTION of a species describes where it is found and the ABUNDANCE of a species determines how many members of that species live throughout the ecosystem.

Question 29

MOD 4 -> * investigate and determine relationships between biotic and abiotic factors in an ecosystem, including: – measuring populations of organisms using sampling techniques

Why do population ecologists collect info on distribution and abundance?

Answer 29

In order to understand and record environmental changes in plant and animal populations over time

Question 30

MOD 4 -> * investigate and determine relationships between biotic and abiotic factors in an ecosystem, including: – measuring populations of organisms using sampling techniques

What affects distribution and abundance?

Answer 30

Abiotic and biotic factors affect the distribution and abundance of organisms in an ecosystem.

Question 31

MOD 4 -> * investigate and determine relationships between biotic and abiotic factors in an ecosystem, including: – measuring populations of organisms using sampling techniques

EXAMPLES OF Abiotic and biotic factors affect the distribution and abundance of organisms in an ecosystem.

Answer 31

E.g. barnacles on ROCKS (where would we find them)
Are there enough trees for nests, do i have to fight for a tree to make my nest, is tehreenough food in that area
MANGROVES: particular carb that loves living near the water - as it moves away from water number becomes less and less -> relies on water as food source

Question 32

MOD 4 -> * investigate and determine relationships between biotic and abiotic factors in an ecosystem, including: – measuring populations of organisms using sampling techniques

Abiotic features in terrestrial environments

Answer 32

In terrestrial enviornments, abiotic factors such as temperature range, light and water availability most commonly affect a species’ abundance and distribution

-> Distribution changes - seasons (whales - too cold to have babies here so move up to queensland) -> animals behaviours change

Question 33

MOD 4 -> * investigate and determine relationships between biotic and abiotic factors in an ecosystem, including: – measuring populations of organisms using sampling techniques

Abiotic features in aquatic environments + difference between _____

Answer 33

In aquatic environments, the importance of each abiotic gactor differs between the two main types of environments: 1. Freshwater, 2. Saltwater. Of course, an estuarine environment (one exposed to both freshwater and saltwater) must deal with constant changes in the environment.

-> Deal with constant changes every few hours - water goes in and out - if you live in estuarine env like mangroves- must be super adaptable - mangrove is estuarine env

Question 34

MOD 4 -> * investigate and determine relationships between biotic and abiotic factors in an ecosystem, including: – measuring populations of organisms using sampling techniques

Examples of biotic factors that may determine the distribution and abundance of a species:

Answer 34

Availability and abundance of foods
Number of competitors
Number of mates
Number of predators
Number and variety of disease- causing organisms

Question 35

MOD 4 -> * investigate and determine relationships between biotic and abiotic factors in an ecosystem, including: – measuring populations of organisms using sampling techniques

Why ecologists also need to determine the distribution of organisms

Answer 35

Ecologists also need to determine the distribution of organism in order to look at any patterns that are formed and the possible reasons for this. This information enables us to determine whether a population is increasing or decreasing in size and what particular aspects of the habitat are favoured over others

-> mangroves area to die - water flow change slightly - even small change caused whole area to die

Question 36

MOD 4 -> * investigate and determine relationships between biotic and abiotic factors in an ecosystem, including: – measuring populations of organisms using sampling techniques

Measuring Abundance of Plants (methods)

Answer 36

There are a few different techniques used to estimate abundance in plants. The one that is simple and easy to use in the field is the percentage cover method. This method uses quadrats (1m x 1m squares) to cover randomly-selected representative areas for estimating the percentage cover of an area. This method is beneficial when plant speices are too high in number to count individually.

Question 37

MOD 4 -> * investigate and determine relationships between biotic and abiotic factors in an ecosystem, including: – measuring populations of organisms using sampling techniques

Measuring Abundance of Plants - percentage cover method

Answer 37

Percentage cover calculations require:
Randomly plotting a number of quadrats (e.g. ten)
Estimating the percentage cover for each one
Finding an average percentage cover
If the area of the ecosystem is known or estimated, then the percentage cover can then be converted to area.
-> works for moss, seaweed, grasses, anything that covers
-> literally a random throw
Obviously, it is a little more difficult to calculate the abundance of animals than plants…

-> quadrat method mainly used for organisms that stay still (plants) or cannot move fast enough to change data (snails)

Question 38

MOD 4 -> * investigate and determine relationships between biotic and abiotic factors in an ecosystem, including: – measuring populations of organisms using sampling techniques

Measuring Abundance of Plants - percentage cover method - when to use quadrats

Answer 38

quadrat method mainly used for organisms that stay still (plants) or cannot move fast enough to change data (snails)

Question 39

MOD 4 -> * investigate and determine relationships between biotic and abiotic factors in an ecosystem, including: – measuring populations of organisms using sampling techniques

Measuring Abundance of Animals (methods)

Answer 39

Mark - release - recapture TECHNIQUE

Estimating abundance is a much easier way of finding out roughly how many animal species exist in an area. Ecologists use a sampling technique called the mark-release-recapture technique:
Animals are captured
The sample animals are tagged then released,
These animals are given time to mix again, recaptured and the number tagged in the sample are counted

Question 40

MOD 4 -> * investigate and determine relationships between biotic and abiotic factors in an ecosystem, including: – measuring populations of organisms using sampling techniques

mark-release-recapture technique formula for calculating abundance

Answer 40

Abundance = number captured x number recaptured/number marked in recapture

Question 41

MOD 4 -> * investigate and determine relationships between biotic and abiotic factors in an ecosystem, including: – measuring populations of organisms using sampling techniques

example of mark-release-recapture technique

Answer 41

1. Capture a random sample of animals from the population is selected
   -> EXAMPLE: Twenty small birds (superb blue wren) were captured, using bird nets - bites scratches, dealing w wild animals - wear gloves, put something over to calm down
2. Mark and release marked animals from the first capture are released back into the natural population and left for a period of time to mix with unmarked individuals
   -> EXAMPLE: the twenty birds are tagged with leg bands and released back into their area and left for three weeks to mix with the population
3. Recapture a sample is captured again to look at the proportion of animals marked from the previous sample
   -> EXAMPLE: after three weeks a second sample of ten birds is captured to find 4 marked birds from the first capture

We now insert the following values into the formula:
Number captured: 20
Number recaptured: 10
Number marked in recapture: 4

Abundance = 20x10/4 = 50
Therefore, we have estimated the total Superb Blue Wren population size in that area as being 50

Question 42

MOD 4 -> * investigate and determine relationships between biotic and abiotic factors in an ecosystem, including: – measuring populations of organisms using sampling techniques

mark-release-recapture technique considerations

Answer 42

This method of assessing the number of organisms in an area (abundance) is quick, inexpensive and provides us with a very accurate number of organisms within the study area.

The number of times that this is performed will affect the accuracy and reliability of results.

Question 43

MOD 4 -> * investigate and determine relationships between biotic and abiotic factors in an ecosystem, including: – measuring populations of organisms using sampling techniques

mark-release-recapture technique assumptions/limitations

Answer 43

ONLY AN ESTIMATE

The mark-release-recapture technique is based on a number of assumptions for accurate estimates of the total population to be calculated:
1. There is no population change through migration, births or deaths between the sampling periods
2. All animals are equally able to be caught (individuals are not ‘trap happy’ or ‘trap shy’ -> time of day they’re active)
-> TRAP HAPPY: The animal may like the bait that is being used to capture it and the same animal may return to the trap on many occasions to get the bait. If food rewards are used, animals may perceive the food reward as worth the discomfort and novelty of entering a hair snare trap -> become trap happy (e.g. antechinus, peanut butter balls)
-> TRAP SHY: occurs when the animal that was captured is unlikely to return to the trap again.
3. Marked animals are not hampered in their ability to move and mix freely with the rest of the population

Limitation - simplistic view - doesn’t take into account migration and organisms moving in and out of an ecosystem

Bird - big net across forest - birds get captured - look at how to capture - ethics - don’t want to injure

Quite labour intensive - disadvantage, but not expensive, anyone can do

Question 44

MOD 4 -> * investigate and determine relationships between biotic and abiotic factors in an ecosystem, including: – measuring populations of organisms using sampling techniques

Measuring distribution -> TRANSECTS

Answer 44

Transects are commonly used in large areas to measure the distribution of a species which gives scientists an idea of the variation thst may occur in an area. A transect is a narrow strip that crosses the entire area being studied from one side to the other.

Question 45

MOD 4 -> * investigate and determine relationships between biotic and abiotic factors in an ecosystem, including: – measuring populations of organisms using sampling techniques

Measuring distribution -> Two examples of transects

Answer 45

Transects provide an accurate and easy method of representing an area simply. Two examples of transects are:
A plan sketch is an aerial or surface view of a representative area within an ecosystem. It shows to scale the distribution of organisms in a measured and plotted view
A profile sketch is a side-on view of an area showing to scale the distribution of organisms along a line.

Question 46

MOD 4 -> * investigate and determine relationships between biotic and abiotic factors in an ecosystem, including: – measuring populations of organisms using sampling techniques

Measuring distribution -> Animals + Evidence

Answer 46

It is more difficult to assess the distribution of animals due to their daily and seasonal movements. When assessing the animals in an ecosystem we can only observe evidence of their existence in the area

E.g. crab hole not all holes are crab holes - estimate and assume

For example, personal sightings, hearing their call, observing their tracks or burrows, and traces such as SCATS (animal faeces) or footprints. Transects can only be used to determine animal distribution for those that hardly move such as barnacle or snails.

Question 47

Quadrats

Answer 47

Square-shaped sampling area, used to estimate abundance over large areas -> Appropriate for sampling plants or slow-moving (sessile) animals

FORMULA:
estimated number of species in an area = total number of individuals counted/area of each quadrat x number of quadrats
THEN x total area

e.g. abundance of weed privet in galston gorge

Question 48

Transects

Answer 48

Involves sampling along a line; used to determine the distribution of organisms (e.g. in relation to changes in abiotic factors) -> Appropriate for sampling plants or slow-moving (sessile) animals -> Can be used to study both mobile + immobile organisms -> useful for along a gradient

FORMULA: depends on measurements taken

e.g. does the abundance of mosses increase closer to rivers?

Question 49

estimating the population size of an organism:

Answer 49

Population size = mean no. organisms in sample area x total area

Question 50

Mark-release-recapture

Answer 50

Used to estimate population abundance -> Appropriate for larger mobile animals

FORMULA:
population size (n) = number captured x number recaptured/number marked in recapture

e.g. population of grey kangaroos

Question 51

MOD 3 -> *conduct practical investigations individually or in teams, or use secondary sources to examine the adaptations of organisms that increase their ability to survive in their environment, including:
– structural adaptations
– physiological adaptations
– behavioural adaptations

Types of adaptations (3)

Answer 51

– structural adaptations
– physiological adaptations
– behavioural adaptations

Question 52

MOD 3 -> *conduct practical investigations individually or in teams, or use secondary sources to examine the adaptations of organisms that increase their ability to survive in their environment, including:
– structural adaptations
– physiological adaptations
– behavioural adaptations

What are adaptations?

Answer 52

Long term evolutionary responses to abiotic factors/selection pressures. Adaptations are characteristics that make organisms specifically suited to the environment in which they live and breed.

Question 53

MOD 3 -> *conduct practical investigations individually or in teams, or use secondary sources to examine the adaptations of organisms that increase their ability to survive in their environment, including:
– structural adaptations
– physiological adaptations
– behavioural adaptations

Structural adaptations??

Answer 53

Structural (physical) adaptations are the characteristics which you can see (outside and in)

actual structures you can SEE - either point to or cut it up and point to it - e.g.
-> fish can change depth in ocean bc internally what they have is a swim bladder - like a balloon - blow up to float up - deflate to sink - only know because of dissection
-> male lions have long manes so that they can puff out their chest as appear large and intimidating to opponents (e.g. in a fight)
-> other e.gs - webbed feet allow to swim, big ears (organisms that live in hot areas) to listen out for predators (hear well) and lose heat, plants also have some

Question 54

MOD 3 -> *conduct practical investigations individually or in teams, or use secondary sources to examine the adaptations of organisms that increase their ability to survive in their environment, including:
– structural adaptations
– physiological adaptations
– behavioural adaptations

Physiological adaptations??

Answer 54

They can not be seen as they are an adjustment in the cell or tissue that gives improved ability to cope with the changing environment

Physiological (functional) adaptations «- hard(er to pin down) apparently
-> keeping cool?
-> Blood sugar levels regulation - adjustments within body organs/cells themselves to improve body to survive
-> homeostasis (phys process - sweat - sweat gets evaporated when fan hits - feel cool) - cant actually see - its how body of organisms works on a cellular level

E.G.
-> camels produce very concentrated urine compared to other mammals IOT (in order to) minimise water loss
-> dont have water in hump -> they have fat - fat gets metabolised which gives them water - regurgitate to redigest - get as much nutrients as possible
-> penguins: never stuck on ice because they have a phys process where they limit amount of blood flow going to feet, feet cold, dont melt, dont stick on ice -> countercurrent heat exchange systems in blood vessels of feet and bill
-> urine concentrated (heavily conc = very yellow, even orange)
-> P for physiological and P for Process - process body undergoing to survive best how structures work and operate on cellular level

Question 55

MOD 3 -> *conduct practical investigations individually or in teams, or use secondary sources to examine the adaptations of organisms that increase their ability to survive in their environment, including:
– structural adaptations
– physiological adaptations
– behavioural adaptations

Behavioural adaptations??

Answer 55

Behavioural adaptations:
Behavioural adaptations are changes in the way an animal acts. These can be taught and developed over a lifetime
-> squirrels collect and store food so they can eat when food is scarce (winter) - collect from good seasons so they have something to eat (something they DO - a BEHAVIOUR that makes them adapted to the env in which they live)
-> burrowing: ground is quite cool
-> nocturnal
-> if good mother stitch young behaviours to survive - if observed not to be good mother adopt and put in zoos
-> passed from gen to another or learnt from other organisms

Question 56

MOD 3 -> *conduct practical investigations individually or in teams, or use secondary sources to examine the adaptations of organisms that increase their ability to survive in their environment, including:
– structural adaptations
– physiological adaptations
– behavioural adaptations

Assumptions about adaptations (riskyyy)

Answer 56

Interfering adaptations - Confounding variables
You have to be very careful with assuming characteristics of an organism are adapted to the environment. The adaptation may be from a past habitat of ancestors
-> doens’t have to be adapt for specific env, could just be passed down from ancestors and happens to be there still

Destiguate structure -> e.g. human appendix

It is also hard to pin down the advantage of adaptations
-> Girrafe have long necks - thought to exist so they can eat leaves others cant get to - not true - most times giraffes will eat off the ground

Question 57

MOD 3 -> *conduct practical investigations individually or in teams, or use secondary sources to examine the adaptations of organisms that increase their ability to survive in their environment, including:
– structural adaptations
– physiological adaptations
– behavioural adaptations

Adaptations for survival in Australian Ecosystems

Answer 57

Australian organisms have adapted to survive harsh conditions such as lack of water, high temperatures and high exposure to sunlight.

Question 58

MOD 3 -> *conduct practical investigations individually or in teams, or use secondary sources to examine the adaptations of organisms that increase their ability to survive in their environment, including:
– structural adaptations
– physiological adaptations
– behavioural adaptations

Plant Adaptations

Answer 58

Xerophytes are plants that have adapted structurally to dry environments by reducing the surface area of leaves in order to minimise water loss.
For example:
- Cactus plants like the mexican lime cactus have small spiky leaves to reduce the loss of water and shallow, widespread roots to catch surface moisture
- The PIGFACE, found on sand dunes, has fleshy stems which store water -> succulent leaves -> near beach - very well adapted on sand dunes - fleshy stems - short (does not grow tall) - FOUND AT BEACH - tastes like salty celery
-> adaptation, stores water in fleshy stems (allows them to survive dry conditions)

-> All spinfex species have tough, pointed and narrow leaves for reducing water loss
-> Sclerophyllous (hard) leaves minimise water loss with a waxy or hairy surface, sunken stomata (reduced to sunlight, closer to ground -hairs on stomate trap humidity around it to not lose water - info in textbook pg 231) or greatly reduced leaves (e.g. desert oak)
-> Succulentl leaves and stems or fleshy underground tubers store water (e.g. parakeelva)

Xerophytic plants in australia - xero meaning dry - spines instead of leaves - native plants in aus have smaller leaves - reducing sunlight on you - reducing water loss

Question 59

MOD 3 -> *conduct practical investigations individually or in teams, or use secondary sources to examine the adaptations of organisms that increase their ability to survive in their environment, including:
– structural adaptations
– physiological adaptations
– behavioural adaptations

Plant Adaptations Examples

Answer 59

Other examples:
- Eucalyptus have a waxy cuticle on their leaves which reflects heat and light to minimise water loss from evaporation (shiny surfaces reflect light)
- Cyprus pines have tiny leaves reducing water loss through transpiration
- Porcupine grasses roll their leaves during the hottest part of the day to allow fewer stomata (leaf pores) to be exposed to the dry atmosphere, therefore less water is lost through (…) - keep humid env in here - roll their leaves

Marrin grass, spinifex similar so put that info in table for that

• Deep-root systems -> australian plants generally -> access deep-water supplies or shallow root systems to enable the rapid uptake of moisture when it suddenly becomes available after rainfall
• Desert acacias (wattles) have leaflets that are vertically flattened and oritned towards the ground, reducing the amount of light) -> PHOTOTAXIS - Wattle reduced in size - less reduced to sun - keeping cool - oriented to the ground

Question 60

MOD 3 -> *conduct practical investigations individually or in teams, or use secondary sources to examine the adaptations of organisms that increase their ability to survive in their environment, including:
– structural adaptations
– physiological adaptations
– behavioural adaptations

Animal Adaptations

Answer 60

For example:
- Kangaroos do not sweat, so they avoid losing water through sweating (physiological)
- The bilby hides in burrows to reduce water loss by evaporation; most desert mammals are nocturnal to reduce exposure to daytime temperatures
- Most aussie animals nocturnal - cooler - kangaroo not losing valuable water to environment - kangaroos licking themselves - evaporative cooling - losing a lil water but not as much as if they were sweating 0 physioligcial (a lil behaviori - overlao)

Kangaroos lick their forelimbs -> behavioural adaptation -> This allows for evaporative cooling

BEHAVIOUR: lots of desert animals in australia are nocturnal

Question 61

MOD 3 -> *conduct practical investigations individually or in teams, or use secondary sources to examine the adaptations of organisms that increase their ability to survive in their environment, including:
– structural adaptations
– physiological adaptations
– behavioural adaptations

Animal Adaptations Examples

Answer 61

Other examples:
- The desert mouse does not need to drink as it gains moisture from food (it is currently on the presumed extinct list) -> metabolises food for water -> nocturnal -> they do burrow
- The spinifex hopping mouse and some desert mammals reduce water loss from excretion by producing highly concentrated urine -> process in body = physiological
- The bilby hides in burrows to reduce the temperature of the environment and lives nocturnally (it forages for food at night when it is cooler)
The bilby has large vascular ears for extra surface area for heat loss

Question 62

MOD 3 -> *conduct practical investigations individually or in teams, or use secondary sources to examine the adaptations of organisms that increase their ability to survive in their environment, including:
– structural adaptations
– physiological adaptations
– behavioural adaptations

Three types of adaptations

Answer 62

Three types of adaptations:
As you can see from the above adaptation examples, there is a large variety in adaptations for just one type of environment (arid), and of that variety of adaptations there are just three types
- Structural - plants that have long, narrow leaf structure in order to reduce water in a desert environment
- Physiological - animal that dilate or swell their blood vessels, bringing them close to the surface of the skin to lose heat more rapidly in a high-temperature environment (vasodilation)
- Behavioural - animals that burrow under the ground to avoid the sun in a desert environment

Reason why you look red when you’re hot - vasodilation - blood vessels are dilating and moving to surface of skin - cheeks getting red - body getting red - blood vessels moving closer to skin to release heat

Question 63

Clownfish + sea anemone

Answer 63

Idneitfying various factors and explaining what would happen if they changed? Clownfish near sea anemone (biotic: predation - bigger fish or eels, competition for sea anemone habitat, comp for plankton and algae they eat, burden of disease) (abiotic: temp of water - change throughout day or year, ox conc of water, levels of acidity and salt in water) -> e.g. of how to relate organism to biotic and abiotic factors -> doesnt have to be direct - can affect species around eg sea anemone (light intens) which in turn affects clownfish

Question 64

MOD 4

Compare the abiotic characteristics of aquatic and
terrestrial environments

Answer 64

Biotic and abiotic factors differ significantly between
aquatic and terrestrial environments. Abiotic factors
create various conditions which suit different types of
organisms and hence affect biotic factors.

Question 65

Predation

Answer 65

An interaction in which one organism, the predator, eats all or part of the body of another organism, the prey

A predator-prey relationship is a type of feeding relationship where the predator obtains its food by killing and eating another animal (the prey).

Question 66

Symbiosis

Answer 66

A close, prolonged association between two or more different biological species that benefits at least one party. There are three types of symbiotic interactions:
mutualism – both species in the relationship benefit
from the association (1/1), commensalism, parasitism.

unusually close and special relationships with members of completely different species

Symbiosis usually involves providing protection, food, cleaning or transportation

Question 67

Commensalism (symbotic relationship type)

Answer 67

Refers to a situation where one species benefits and the other is unaffected (neither harmed nor helped) (1/0)

Question 68

Parasitism (symbotic relationship type)

Answer 68

A relationship in which one species benefits and the other is harmed or suffers (usually) non-lethal damage

A parasite obtains food and shelter from the host organism. They feed upon the tissues or fluids of the host organism, but do not usually kill it, as this would destroy the parasite’s food supply.

The parasite is often smaller than their host and they may live on the surface of their host (OUTER -> ectoparasites, e.g. ticks, fleas and tinea) or internally (INSIDE -> endoparasites, e.g. tapeworms)

Question 69

Allelopathy

Answer 69

The production of specific biomolecules by one plant that can be beneficial or detrimental
to another plant.

There are several different types of allelopathy.

In one type, the plant that is protecting its space releases growth compounds from its roots into the ground. New plants trying to grow near the allelopathic plant absorb those chemicals from the soil, inhibiting root/shoot growth or seed germination.

Another type of allelopathy involves the release of chemicals that slow or stop the process of respiration or photosynthesis, and some chemicals may inhibit nutrient uptake. Plants may also release chemicals that can change the amount of chlorophyll (absorb light) in another plant. The plant cannot then make enough food with the changed chlorophyll levels and dies.

Allelopathic chemicals can be present in any part of the plant

Question 70

Mutualism

Answer 70

a relationship between 2 species from which both partners get some benefit. None harmed. They may be unable to live separately

-> EXAMPLE: LICHEN -> plants that can grow on bare rocks and other hostile places -> composed of alga and fungi living together. the (GREEN) algae provides food for itself and the fungus by photosynthesising and the fungus stores necessary water for both organisms (provides moisture - top fungal layer holds in water + anchorage - through fungal hyphae)

-> EXAMPLE: root nodules are lumps which appear on the roots of leguminous plants like peas, beans, clover and lupins. they contain bacteria called rhizobium which can take nitrogen gas from the air and change it into a form (nitrates) the plant can use to help it grow. in return it gets food from the plant.

-> EXAMPLE: The relationship between the CLOWNFISH (or anemone fish) and the SEA ANEMONE. The anemone fish is neither stung nor eaten by the anemone. The anemone fish repeatedly brushes against the anemone’s tentacles until its own mucous coating inhibits the anemone’s sting. The anemone fish is therefore protected from predators by hiding in the anemone’s tentacles unharmed. It feeds on the anemone’s food scraps. The anemone benefits as the anemone fish cleans its host and lures other animals into the anemone’s tentaclesde

Question 71

Commensalism

Answer 71

relationship between 2 species in which one partner (the commensal) or both, gets some benefit, while the other (the host), neither gains nor loses. neither harmed

-> EXAMPLE: hermit crabs (host) + sea anemone (commensal) -> crabs occupy empty shells of dead animals, such as whelks, in order to get protection for their soft, vulnerable bodies. Sea anemones and other animals attach themselves to this shell so they can get transport and scraps of food from the crab. IN return, the crab usually gets very little of value

-> EXAMPLE: shark (host) + remora fish (commensal) -> remora attaches itself to a shark by using a sucker on the top of its head, gets carried around by the shark with its mouth free to catch bits of food the shark may drop. shark appears to be completely unaffected.

-> epiphytic ferns, which attach themselves to the trunks of large rainforest trees as a means of support. They appear to benefit from living on the trunk of the host tree by catching rainwater to dissolve nutrients and by being closer to sunlight

-> EXAMPLE: BARNACLES + WHALES
The barnacle is a crustacean that normally adheres to a fixed surface; however, some barnacles adhere to the surface of whales and turtles. This does not affect the whales or turtles, but benefits the barnacles as they are transported to diverse areas rich in food (plankton)

Question 72

Parasitism

Answer 72

a relationship between two species in which one (parasite), gets food and shelter from the other (host), while causing some degree of harm to it, perhaps eventually killing it (parasitoid)

-> EXAMPLE: tapeworms live in intestines (hooks + suckers to hold to walls) of humans + other animals which have eaten infected meat. their long (up to 6m) flat bodies absorb the person’s digested food, while special chemicals keep the worms from being digested themselves. segments full of ripe eggs are passed in the person’s faeces to spread the infection.

-> EXAMPLE: fungi are often parasites, causing disease and death to their hosts, mainly plants. spores land on the plant and germinate. the fungal hyphae spread through the plant tissues, feeding on the cells and killing them. the fungus then produces more spores to spread the disease to other plants

Question 73

allelopathy

Answer 73

a detrimental relationship in which one plant reduces the growth of another one in its vicinity by secreting inhibitory chemicals (or beneficial ones)

-> many eucalypt species produce toxic chemicals that inhibit the growth of seedlings of otehr species underneath their canopies

Not all plants have allelopathic tendencies, but most plants do use it to compete with other plants and therefore negatively influence the existence of neighbouring plants. Basically, it is mainly used by plants to keep plants out of its space (survival of the fittest) -> Space is crucial to the survival of plants. The fewer plants around, the more water to absorb from the soil, the more soil to support the roots for plants stability, and the more sunlight available to absorb

Question 74

predation

Answer 74

a detrimental relationship in which one organism kills and eats another one

Predator population is dependent on prey population (4 year cycle)

The population size of a predator always rises and falls after the prey population.

Predator population always lower than prey - predator rises and falls after prey population because the pred population is dependent on prey pop for change in size (prey is not dep)

The predator population will not change as soon as the prey population changes. If there is a sudden increase in the prey population, it will take time for more predators to be born, survive, and benefit from the additional food.

Question 75

competition

Answer 75

Competition occurs when two or more organisms use one or more resources in common such as food,
shelter and mates. The competition is usually for a resource in the environment that is limited in
supply but valuable to survival. Organisms may compete with members of their own species
(intraspecific competition) or members of another species (interspecific competition).

an interaction between organisms or species in which both require a resource that is in limited supply (such as food, water, or territory). it lowers the fitness of both organisms involved, since the presence of one of the organisms always reduces the amount of the resource available to the other

Question 76

decomposers

Answer 76

Decomposers in ecosystems
-> decomposer organisms use the energy of dead organisms for food and break them down into materials which can be recycled for use by other organisms. Bacteria and fungi in the soil are very important because they return nutrients to the soil when they decompose dead animals and plants.

(The highly important cycle operating in this process is the nitrogen cycle. Nitrogen is essential to all living things)

BALANCED ECOSYSTEM

Decomposers play a critical role in the flow of energy through an ecosystem. They break apart dead organisms into simpler inorganic materials, making nutrients available to primary producers

Question 77

three categories of food chain

Answer 77

producers, consumers, decomposers - all dependent on each other

Question 78

producers

Answer 78

get their food + energy from the sun (plants). make their food through photosynthesis
Producers use energy and inorganic molecules to make food.

Question 79

consumers (3 types)

Answer 79

need to eat their food to get energy (animals)

Consumers take in food by eating producers or other living things.

3 types: carnivore (meat only), herbivore (plants only), omnivore (both)

Question 80

decomposers

Answer 80

Decomposers break down dead organisms and other organic wastes and release inorganic molecules back to the environment (turn back into soil or dirt)

-> mushrooms, worms, bugs

Question 81

graphing (5)

Answer 81

title, start at 0, label axes (x - indp, y - dep), even scale
LABEL AXES W UNITS

Question 82

aim

Answer 82

to investigate…
mention indp + dep variable
include ‘effect’

Question 83

hypothesis

Answer 83

if…then…

Question 84

conclusion

Answer 84

address aim/hypothesis - proven true or not
state trend (refer to)

In this experiment, it was found that… as seen in .. (results)… and this proves hypothesis

(Based on this trend), I found the trend was that… my data showed this …. consistent with hypothesis. therefore hypothesis was true/proven

was found as evident in… represented in data, which showed that…