Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biology > Ecology and the Environment > Flashcards

Ecology and the Environment Flashcards

1
Q

population

A

all individuals of one species at one place at one time. E.g. all magpies in my garden at one time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

community

A

all populations at one place at one time. E.g. every living organism (animals, plants) in my garden at one time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

habitat

A

the places where a specific organism lives (whales - the ocean)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

ecosystem

A

as all the biotic factors and all the abiotic factors that interact within an area at one time (eg a garden pond)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

species

A

one type of creature (eg hoeosapions)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

4.2 - practical investigate the population size of an organism in 2 different areas using quadrats

A
  1. use 2 tape measures to lay out a survey area (eg 10m x 10m)
  2. use a random number generator to create a set of coordinates to place the quadrat
  3. count the number of chosen species within the quadrat
  4. repeat steps 2-3 10x
  5. estimate the number of species in entire area with the formula:
    find mean species per quadrat x total area of survey area

repeat entire process in a different area

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

whats a quadrat

A

Quadrats are square frames made of wood or wire
They can be a variety of sizes eg. 0.25m2 or 1m2
They are placed on the ground and the organisms within them are recorded

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what can quadrats measure

A

The number of an individual species: the total number of individuals of a single species (eg. buttercups) is recorded

Species richness: the total number of different species (but not the number of individuals of each species) is recorded

Percentage cover: the approximate percentage of the quadrat area in which an individual species is found is recorded (this method is used when it is difficult to count individuals of the plant species being recorded eg. grass or moss

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

biotic factors

A

living

Competition
Predator-prey relationships
Interactions with other organisms within the food chain or food web

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

abiotic factors

A

non-living

Light intensity
Mineral availability
Water availability
pH
Temperature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what does biodiversity mean

A

the range and variety of different species of organisms on Earth, or within an ecosystem

It considers not only the species richness but the variation within each species, its distribution and population size

E.g. a high biodiversity would be found in an environment with lots of different species which show a lot of variation and are living in, all evenly distributed across the study area

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

4.4B practical - investigate the distribution of organisms in their habitats and measure biodiversity using quadrats

A
  1. Use 2 tape measures to lay out your first survey area (e.g. 10m X 10m)
  2. Use a random number generator to create a set of coordinates to place your first quadrat
  3. Count the number of different species and the number of each species found within that quadrat
  4. Repeat this process until you have collected the data for 10 quadrats
  5. Repeat these steps for the second survey area

the area with the greatest number of different species and the number of each species

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

species evenness

A

total number of organisms of each species in a place

for example if there was 2 oak trees, 2 spruce trees and 2 birch trees in one place and
4 oak trees, 1 spruce tree and 1 birch tree in another place

the first place would have the good evenness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

species richness

A

the number of different species present in a place

eg. oak, spruce, birch, jungle = 4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

how does light intensity affect communities

A

abiotic

light is needed to photosynthesis. more light leads to an increase in photosynthesis rate and an increase in plant growth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

how does temperature affect communities

A

abiotic

affects photosynthesis rate in plants and therefore growth in plants

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

how does moisture levels affect communities

A

abiotic

plants and animals require water to survive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

how does soil pH and mineral content affect communities

A

abiotic

less mineral ions will negatively affect plants as they won’t be able to osmosis as well

changing pH affects plants as they are adapted for certain conditions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

how does CO2 levels affect communities

A

abiotic

CO2 is required for photosynthesis so CO2 conc affects photosynthesis rate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

how does O2 levels affect aquatic animals

A

abiotic

affects aquatic animals as they can only survive in water with high O2 conc

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

availability of food

A

biotic

more food means organisms have a higher chance of survival and reproducing. this means the population will increase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

new predators

A

biotic

in balanced ecosystems predators catch enough prey to survive but not enough to wipe out the population. if a new predator is introduced then it could unbalance the ecosystem

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

new pathogens

A

biotic

if a new pathogen enters an ecosystem the populations living their will no longer have immunity which will put the populations in decline

24
Q

competition

A

biotic

if 2 species compete for the same resources and one is better equipped to to take advantage of the food, the better equipped one will get the resources meaning the other species will decline

25
Q

producer

A

they produce their own energy

eg plants photosynthesing

26
Q

primary consumer

A

the organisms which eat the producer

eg sheep who eat the grass

27
Q

tertiary consumer

A

feed on the secondary consumer

28
Q

secondary consumer

A

feed on the primary consumer

29
Q

what is a trophic level

A

a different stage of a food chain

eg one trophic level might be the primary consumers

30
Q

decomposer

A

organisms (bacteria and fungi) which secrete digestive enzymes to decay dead organic matter to obtain their food, these help recycle nutrients

31
Q

what does a food chain show

A

a simple way to show the feeding interactions between organisms in a community

the arrows show the direction that the energy is travelling in

32
Q

what does a food web show

A

shows a more complex version and accurate version of the feeding interactions between the organisms in a community
can also show interdependence (how the change in one population can affect others)

33
Q

what does a pyramid of number show

A

A pyramid of numbers shows how many organisms at each level of a food chain.

You cannot change the trophic level of the organisms - they must stay in the same order as in the food chain with producers on the bottom, followed by primary consumers, then secondary consumers, then tertiary consumers
this is why the pyramid of number is slightly flawed

the pyramids always has the first thing on the food chain at the bottom and then the second and etc

34
Q

what does a pyramid of biomass show

A

shows the total mass of the organisms in each trophic level (i.e. the mass of an individual x the number of individuals).

These are a more accurate way of looking at the relative amounts of organisms

these are always more like a normal pyramid
This is because the mass of organisms has to decrease as you go up a food chain – if we take our first food chain as an example, it’s impossible to have 10kg of grass-feeding 50kg of voles feeding 100kg of barn owls

35
Q

what does a pyramid of energy transfer show

A

Pyramids of energy illustrate the amount of energy contained within the biomass of individuals within different trophic levels

The area of each box represents the quantity of energy present

These pyramids always have a wide base (due to the large amount of energy contained within the biomass of producers)

As you move up the pyramid to higher trophic levels the quantity of energy decreases as not all energy is transferred to the biomass of the next trophic level (roughly only 10 % of the energy is passed on)

36
Q

how does the transfer of energy and substances work in a food chain

A

Energy flows from the sun to the first trophic level (producers) in the form of light
Producers convert light energy into chemical energy
This occurs during photosynthesis, when producers convert carbon dioxide and water into glucose and oxygen
Producers use this glucose (during respiration) to produce their own biomass
When primary consumers consume (eat) producers, they break down the biomass of the producer (digestion) and use the chemical energy to increase or sustain their own biomass
When secondary consumers consume (eat) primary consumers, they break down the biomass of the primary consumer (digestion) and use the chemical energy to increase or sustain their own biomass, and so on
In this way, as chemical energy is transferred from one trophic level to the next, biomass is also transferred

37
Q

what is biomass

A

Biomass is a store of chemical energy

38
Q

how much energy is lost between each trophic level

A

ruffly 90% is lost between each trophic level

39
Q

why do food chains rarely contain more than 6 trophic levels

A

the total amount of energy available eventually becomes too small to support another trophic level as 90% is lost between each level

40
Q

how is energy lost at each trophic level

A

Organisms rarely eat every part of the organism they are consuming – some of the biological material of plants and animals may be inedible

Not all the ingested material is digested and absorbed, some is egested as faeces

Energy is used for movement

Energy is used to generate heat

Energy is used for metabolic processes

Some absorbed material is lost as waste:
Carbon dioxide and water are waste products of respiration
Water and urea are the waste products in the urine, which is produced when proteins are broken down

41
Q

what is the role of the nitrogen fixing bacteria

A

takes N2 gas and change it into nitrates in the soil

42
Q

what is the role of decomposers

A

When the animals and plants die, they decay and all the proteins inside them are broken down into ammonium compounds and put back into the soil

43
Q

what is the role of nitrifying bacteria

A

convert the ammonium compounds (from the decomposers) to nitrites and then to nitrates

44
Q

what is the role of denitrifying bacteria

A

take the nitrates out of the soil and convert them back into N2 gas

45
Q

why can’t animals and plants absorb nitrogen out of the air

A

N2 gas is very stable and the bonds holding the nitrogen atoms together would need massive amounts of energy to break (the two nitrogen atoms in a nitrogen molecule are held together by a triple covalent bond)

46
Q

why do we need nitrogen

A

Nitrogen as an element is required to make proteins

47
Q

what is nitrogen fixing

A

nitrogen taken out of the air and converted into something easier to absorb such as nitrates

48
Q

what nitrogen fixes

A

lightning

nitrogen fixing bacteria

49
Q

how does lighting nitrogen fix

A

splitting the bond between the two atoms and turning them into nitrous oxides like N2O and NO2 that dissolve in rainwater and ‘leach’ into the soil

50
Q

how does the fixed nitrogen get removed from the soil

A

denitrification (bad denitrifying bacteria)

plants actively transport N ions into their roots

51
Q

how does nitrogen get put into the soil

A

nitrogen fixing (lighting or nitrogen fixing bacteria)

nitrification (nitrifying bacteria)

52
Q

how do animals get nitrogen

A

eat the plants (or other animals) which contain amino acids and proteins

53
Q

how do plants get nitrogen

A

plants actively transport N ions into their roots

54
Q

how do animals get rid of the nitrogen

A

waste (urine and faeces) which puts the nitrogen back into the soil as ammonium compounds

55
Q

how does denitrifying bacteria work

A

they are found in poorly aerated soil which mean they respire anaerobically which puts the nitrogen straight out of the soil and into the air again

56
Q

how to prevent denitrifying bacteria

A

by ploughing and turning over soil (aerating)

Biology (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions