Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

BIOLOGY A LEVEL > CHAPTER 24 - POPULATIONS AND SUSTAINABILITY > Flashcards

CHAPTER 24 - POPULATIONS AND SUSTAINABILITY Flashcards

1
Q

What are the 3 main phases of a population growth curve

A

Slow growth

Rapid growth

Stable state

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

What is immigration

A

The movement of individual organisms into a particular area, increasing population size

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

What is emigration

A

The movement of individual organisms away from a particular area, decreases population size

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

What is an environments carrying capactiy

A

The maximum population size that an environment can support

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

State 3 factors that would cause an increase in population size

A

increase in quantity or quality of food supply

availability of (clean)
water

lack of predators

favourable environmental conditions

availability of light

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

Describe what happens during a period of exponential population growth

A

The population doubles in size / increases by a fixed proportion

each time a fixed interval of
time elapses

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

What is interspecific competition

A

Competition between different species

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

What is intraspecific competition

A

Competition between members of the same species
(pg 636)

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

What does competition fight for

A

Interspecific - habitats, food, territory,

Intraspecifc - above + mating

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

What is the competitive exclusion principle

A

Where two species are competing for limited resources

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

What is an example of interspecific competition

A

Red and grey squirrels

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

What is an example of intraspecific competition

A

Robins competing for breeding territory, food etc…

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

State the difference between interspecific and intraspecific competition

A

Interspecific competition is when members of different species compete for the same resource
whereas intraspecific competition is when members of the same species compete for a resource

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

Describe the cycle of population size changes that occur as a result

A

Initially resources plentiful so population increases in size

resources now limited as more
organisms compete for resource, resulting in population decrease

reduced population results in
less competition so organisms survive and reproduce, resulting in increased population

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

Oak tree saplings compete with each other for light, water and minerals.

State the type of competition that exists between oak tree saplings

Suggest how the population of oak trees will vary over time

A

intraspecific competition

The individuals which grow fastest / are better adapted will survive

as saplings grow taller
they will reduce light / other named resource for other saplings

this will result in death of other
saplings / only few dominant oak trees will survive

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

What is predation

A

Where an organism kills and eats another

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

What adaptions do predators have

A

Sudden bursts of speed, stealth and fast reactions

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

What adaptions to prey have

A

Mimicry, camouflage, defence mechanisms (eg. spines)

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

What are the stages of predator-prey relationships

A

Increase in prey provides more food and the predators, allowing more to survive and reproduce, increasing predator population

Increased predator population eats more prey organisms, causing a decline in prey population

Reduced prey means it cannot support a large predator population, so competition for food increases, decreasing size of predator population

Reduced predator numbers means less prey are being killed, so they can reproduce increasing population
(pg 637)

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

Describe what would happen to the numbers of a predator population if a fatal disease spread amongst its only prey

A

Predator population would also fall as it has no food

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

Suggest two reasons why the populations of an interlinked predator and prey don’t produce an identical graph to expected

A

The prey is not only food source -
therefore can get energy by eating another animal, so a decrease in this particular prey will not necessarily cause a decrease in the predator population

predators contract a fatal disease -
prey population can increase dramatically

natural disaster - destroys both populations

seasonal fluctuations e.g., larger plant growth in
summer - increases prey food source so numbers climb

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

What is conservation

A

Maintaining of biodiversity through human action or management, including maintaining diversity between species, maintaining habitats and genetic diversity within a species

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

What is reclamation

A

process of restoring ecosystems that have been damaged or destroyed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What is preservation

A

The protection of an area by restricting or banning human interference, so the ecosystem remains in its original state

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Why is conservation important
Economic benefit - to provide resources to survive and provide an income Social - many people enjoy the beauty of a wild ecosystem, which are beneficial to health by relaxing and exercise Ethical - all organisms have a right to exist
26
State the difference between conservation and preservation
Conservation active management of an ecosystem Preservation protection of an ecosystem from interference so that it remains in its original state
27
What are some methods of conservation/reclamation
Controlled burning, halting succession
28
What is a sustainable resource
A renewable resource that is being economically exploited in such a way that it will not diminish or run out
29
What are the aims of sustainability
Preserve the environment Ensure resources are available for future generations Allow humans in all societies to live comfortably Enable LEDCs to develop through exploiting their natural resources Create more even balance in the consumption of these resources between MEDCs and LEDCs
30
What is coppicing
A tree trunk is cut close to the ground, new shoots from from the cut surface and mature Shoots have many uses, including fencing (pg 642)
31
What do large scale timber companies do to ensure production is sustainable
Practise selective cutting, only removing largest trees Replacing trees through replanting Planting trees optimal distance apart to reduce competition Manage pests and pathogens to maximise yields Ensure that areas of forest remain for indigenous people
32
What techniques are used to reduce overfishing
Use of different mesh sizes - making mesh larger so immature fish can escape and breed Allow commercial and recreational fishing only at certain times of the year Introduction of fish farming to prevent loss of wild species
33
Suggest two reasons why producing resources in a sustainable way is important
To preserve the environment (1); to conserve / make available resources for future generations to maintain biodiversity in an area to allow LEDCs to develop by exploiting their natural resources to create a more even balance in the consumption of resources between LEDCs and MEDC
34
Explain how coppicing is used to produce a sustainable supply of timber
In one area trees cut close to ground timber is used for fuel / fencing / building / other appropriate use new shoots appear which are allowed to grow another area of land is then coppiced when initial trees reach a certain height they are then coppiced and cycle begins again
35
What is the Masai Mara ecosystem
Savannah, and the mara river
36
What are the key principles of ecotourism
Ensure tourism doesnt exploit the natural environment or local communities Consult and engage with local communities on planned developments Ensure that infrastructure improvements benefit local people as well as visitors
37
What are the current studies in the masai mara
Behaviour and physiology of the predator spotted hyena Flow assessment of the river basin Mara predator project, cataloguing and monitoring lion populations Mara-Meru cheetah project, monitoring cheetah populations
38
State two ways in which humans use the lands of the masai mara
Tourism / ecotourism and farming / grazing
39
How is the human and animal population balance maintained in the masai mara
Elephants threaten crop cultivation, so crops have to be fenced off (eating and trampling) Legal hunting to cull excess animals Diseasing migratory animals Human populations expands more homes than are required
40
Explain how and why the local masai tribes have changed their style of farming in recent years
Tribes of region were traditionally semi-nomadic / equivalent tribes of Masai have been restricted to using certain defined areas / use areas around the game reserve larger population density in these regions land farmed more widely / more land used for agriculture land farmed more intensively / greater reliance on fertilisers
41
The masai mara region receives 300000 visitors each year. State and explain the positive and negative impacts of this influx of people in the region
People bring economic input into region (1); which creates jobs / enables region to invest in infrastructure / technology / transport links / other relevant example (1); visitors see local tribes (1); allows for continuation of traditional culture pastimes / educates visitors about their traditional way of life (1); research is carried out in the Masai Mara (1); providing employment / improved facilities / better conservation approaches / ensuring maintenance of biodiversity in the region (1); large visitor numbers requires infrastructure (1); can damage environment / uses natural resources / affects local habitat (1); visitors / safaris require transportation (1); leads to soil erosion / scares anima
42
What is the ecosystem of the Terai region in Nepal
Forest and floodplains
43
What are some of the successes in the Terai region in community forestry groups
Significant improvements in conservation of forest regions Improved soil and water management across the region Increase in the retail price of forestry products Employment and income generation through forest protection Sustainable wood fuel sources Securing the biodiversity of the forested area
44
How have management strategies for sustainable land use in the Terai region prevented degradation of terai forests
Promoting the production of fruits and vegetables in the hills and mountain regions to avoid further intensification of the Terai Improving irrigation facilities to enhance crop production Multiple cropping, more than one crop is grown on a piece of land each season Growth of nitrogen fixing crops Growing crop varieties resistant to various soil challenges, through biotech and genetic engineering Improving fertilisation techniques
45
Describe the ecosystem of the terai region of Nepal
Mixture of fertile agricultural land, with densely forested regions region is hot and humid in the summer months / subjected to monsoons (in rainy season
46
State two ways humans use the Terai region of Nepal
growing crops / agriculture forestry / felling timber for building products / burning as fuel tourism
47
Explain how sustainable forestry and agricultural practices are being used in the Terai region to maintain biodiversity, while also meeting the needs of the local population
Local community forestry groups have been established to set harvesting rules / set agreed prices for timber products / reinvest profits for the benefit of the local population / enable small businesses to gain FSC certification Sustainable forestry practice has: Increased forested area / forested density therefore larger region available to support biodiverse ecosystem / improved water management / provided improved economic income to the region Sustainable agriculture has: Prevented further intensive agriculture in region therefore retained biodiversity of less cultivated regions / improved irrigation of land / encouraged multiple cropping / planting of leguminous crops / encouraged planting of disease / climatic / biotic-factor resistant crops / improved fertilisation of land
48
State what is meant by a peat bog
A region of spongy, waterlogged land containing decomposing vegetation
49
What are some conservation measures taken to conserve areas of lowland bogs
Ensuring the peat and vegetation of the bog so it is undisturbed and as wet as possible Removal of seedling trees in the area Using controlled grazing to maintain the biodiversity
50
State and explain why the UK has lost such a large proportion of its peatlands over the past century
Peat is used for fuel / as a gardeners’ soil additive therefore peat has been removed from the land to supply human demands intensive farming / irrigation / drainage of land / afforestation / other relevant effect has removed water from the wetlands drying out peatland regions thus leading to degradation or destruction of the peatlands
51
What are some management techniques used to manage environmentally sensitive areas
Limiting the areas a tourism can visit Controlling the movement of livestock Introducing anti-poaching measures Replanting of forests and native plants Limiting hunting through quotas and seasonal bans
52
What are three distinct regions in the galapagos which support particular plant species
Coastal zone, containing salt-tolerant species eg. mangrove and saltbush Arid zone, containing drought-tolerant species eg. cacti, carob tree Humid zone, containing dense cloud forest eg. supporting mosses and liverworts
53
What are some of the protective measures of the Galapagos national park
Introduction of park rangers across the islands Limiting human access to particular islands Controlling migration to and from the islands Strict controls over movement of introduced animals
54
What are the human impacts on Antarctica
Planet-wide impacts eg. global warming Hunting of whales, seals and fishing have depleted stocks of these organisms Soil contamination Discharge of waste into the sea
55
What does the Antarctic treaty 1961 state in its provisions
Scientific cooperation between nations Protection of plants and animals Designation and management of protected areas Management of tourism
56
What are the key purposes of the National park authority in Snowdonia
Conserve and enhance national beauty, wildlife and cultural heritage Promote opportunities for understanding and enjoyment Enhance economic and social wellbeing of communities within the park
57
State 3 reasons why people might want to visit environmentally sensitive areas
to view rare or endangered species, to experience the landscape, for recreational opportunities
58
State one unique feature of the Galápagos Islands and of Antarctica
G: Islands have never been connected to mainland / no large natural predators exist / almost complete absence of mammals A: Extremely cold / dry / extended periods of sunlight or darkness / almost entirely covered by ice sheet / other relevant feature
59
Using a named region, state and explain how a human activity is controlled to limit its effect on the populations of flora or fauna
e.g., Antarctica e.g., whaling e.g., reduction in population of fin whales e.g., worldwide ban on whaling
60
Environmentally sensitive regions often receive many visitors each year. State and explain the social and environmental impacts on the region of this influx of people
eg. Snowdonia national park Social: Visitors bring money (1); which creates jobs (1); enhances local population (1); reduces rural depopulation allows rural regions to be economically viable enable rural areas to invest in infrastructure (1); technology (1); supports local businesses (1); transport links (1); (leisure) facilities created for visitors (1); also benefit local people (out of season) / other relevant example (1); many visitors (1); can cause congestion / overcrowding / disturbs tranquillity / can bring invasive species / transmit disease / other relevant example (1). Environmental (max 4): Visitors bring money (1); which can be reinvested in conservation projects / other relevant example (1); visitors raise profile of a region (1); to enable environmental campaigns to gain publicity / other relevant example (1); many visitors (1); cause erosion of paths / trampling of flora / poaching / removing species from habitat

BIOLOGY A LEVEL (24 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions