B16 - Adaptations, interdependence and competition

Question 1

What are the 4 size levels in an ecosystem?

Answer 1

-organism
-population
-community
-ecosystem

Question 2

Define population:

Answer 2

all the organisms of a particular species in a habitat

Question 3

Define community:

Answer 3

all the populations of the different species in a habitat

Question 4

Define ecosystem:

Answer 4

interaction of a community of living organisms (biotic) with the non-living (abiotic) parts of the environment

Question 5

What do organisms need to survive and reproduce?

Answer 5

a supply of materials from their habitat and from other living organisms there

Question 6

What 3 things do animals compete for?

Answer 6

-food
-territory
-mates

Question 7

What 4 things do plants compete for?

Answer 7

-light (PS)
-water (PS + rigid tissues)
-space (to grow into)
-nutrients and minerals (growth)

Question 8

What is competition?

Answer 8

process of which living organisms (of the same/different species) interact with each other to gain limited resources such as food

Question 9

Why is competition important in a community?

Answer 9

drives the process of natural selection, so that the more successful organisms are able to reproduce more, increasing their population

Question 10

2 different species of birds live on Isabela island - suggest why:

Answer 10

-Isabela island is a very big island which would have more food/seeds available for the birds to eat
-less competition for food/seeds, as there is enough for both species to eat

Question 11

What is interdependence?

Answer 11

the network of relationships between different organisms in a community, showing how all species rely on others

Question 12

How can interdependence affect a community? Provide some examples of what it is important for:

Answer 12

-if one species is removed/decreases in numbers, the whole community will be affected in some way due to interdependence

-important for food, shelter, seed dispersal and pollination

Question 13

What is a stable community? Give 2 examples:

Answer 13

a community (define community) where all the species and environmental factors are in balance so population sizes remain fairly constant

-ancient oak wood
-coral reef

Question 14

What is an abiotic factor?

Answer 14

any non living aspect of an environment that can affect another organism or shape the ecosystem in some way

Question 15

Give 7 examples of abiotic factors:

Answer 15

-wind intensity/direction
-light intensity
-moisture
-temperature
-soil pH and mineral content
-oxygen levels (aquatic animals)
-carbon dioxide levels (plants)

(W, LMT, SOC)

win limited sock

Question 16

Define biotic factor:

Answer 16

any living aspect of an environment that can affect another organism or shape the ecosystem in some way

Question 17

Give 3 examples of biotic factors:

Answer 17

-food availability
-one species outcompeting another so the numbers are no longer sufficient to breed
-new predators/pathogens

Question 18

What is an adaptation?

Answer 18

a feature that enables an organism to survive in the conditions present in their habitat

Question 19

Describe the 3 types of adaptations and provide examples:

Answer 19

-structural (physical features, eg colour)
-behavioural (how they behave in response to a stimulus, eg migration)
-functional (chemical processes in the organism, eg producing less sweat/urine)

Question 20

Name 3 plant adaptations:

Answer 20

-deep/wide root system
-water-storing tissue (eg cacti)
-thick waxy cuticle

Question 21

How does this show that beak depth is an inherited characteristic?

Look at this graph.

Answer 21

offspring have a similar beak depth to their parents

ignore positive correlation/description of it

Question 22

What are extremophiles? Give an example:

Answer 22

-organisms with adaptations that allow them to live in environments of extreme conditions (high salt, temperature, pressure)

-bacteria living in deep sea vents

Or tardigrades (an animal)

Question 23

What is an advantage that extremophiles have?

Answer 23

very little competition in their extreme habitat (eg deep sea vents)

Question 24

RP9 - What are the 2 methods of sampling?

Answer 24

-quadrats (abundance of organisms within a certain area)
-transects (distribution of organisms with respect to changing abiotic factors along a straight line)

These methods will only work with plants or slow moving animals

Question 25

RP9a - How would you randomly select areas within a habitat to sample a species?

Answer 25

-set up 15x15m area split into 1x1 squares
-use random number generator to get at least 20 pairs of coordinates (>10% of sample size to ensure the sample is representative)

Always mention using coordinates in this method to achieve randomness

Question 26

RP9a - How could you use a quadrat to sample the plant’s population size within your predetermined 15x15m area?

Answer 26

-set down 1x1m quadrat at coordinate
-count number of organisms in quadrat
-repeat with all the other samples (>10% of sample size)
-calculate total population size using ratios

sampled area : organisms counted
total area : x

Question 27

RP9a - Why might using a mean value for the number of organisms per quadrat be less accurate?

Answer 27

-might have a small sample size
-might not be representative of the entire area

Question 28

RP9b - How and where would you set up a transect to investigate the effect of changing an abiotic factor?

Answer 28

-lay down a tape measure from a start point to an end point

-use an area with an environmental gradient (ie a change in abiotic factors)

Question 29

RP9b - How would you use continuous/systematic sampling along your predetermined transect line?

Answer 29

-put down a quadrat at regular intervals at least 10 times
-count number of organisms within each one
-record how many are at the specified distance along the transect
-record the abiotic factor at each sampling site

Remember to note what abiotic factor you are investigating (eg light intensity)

Question 30

How does camouflage help as an adaptation?

Answer 30

-blends in with surroundings
-so predators can’t see the organism

Question 31

Why would being brightly coloured help as an adaptation?

Answer 31

(remember to mention what colour it is in the question)
-warns predator that it might be dangerous/poisonous

Question 32

Why do flowers that grow underneath trees always have enough mineral ions?

Do not refer to shade

Answer 32

-leaves from tree fall to ground and are decayed by decomposers
-mineral ions/nutrients released into soil
-taken up by flower roots later

Question 33

Wasps have stings but hoverflies don’t - why does having stripes on the hoverfly help it avoid being eaten by predators?

Answer 33

-mimics a wasp
-predators think it has a sting