Unit 5 Test

Question 1

Biodiversity

Answer 1

a broad concept encompassing total diversity which includes diversity of species, genetic diversity and habitat diversity

Question 2

Species diversity

Answer 2

is a product of two variables, the number of species (richness) and their relative proportions (evenness).

The variation in diversity varies from habitat to habitat

Question 3

Genetic diversity

Answer 3

is the range of genetic material present in a gene pool or population of a species.

Not all species have the same amount of genetic diversity

Humans can alter genetic diversity by artificially breeding or genetically engineering populations with reduced variation in their genotypes or even identical genotypes - clones.

Question 4

Habitat diversity

Answer 4

is the range of different habitats per unit area in a particular system or biome

Question 5

biodiversity hotspot

Answer 5

is a region with a high level of biodiversity that is under threat from human activities.

Question 6

natural selection

Answer 6

those more adapted to their environment have an advantage and flourish and reproduce but those less adapted do not survive long enough to reproduce.
“Survival of the Fittest”

Question 7

Summary of the theory of evolution

Answer 7

Each individual is different due to their particular set of inherited genes and to mutations

Each will be slightly differently adapted to its environment

Resources are limited for any population and there will be competition for these resources (eg for food, light, space, water)

Over time these changes show and the whole population gradually changes

Question 8

Speciation

Answer 8

the formation of new species when populations of a species become isolated and evolve differently.

Question 9

Isolation of Populations

Answer 9

can be caused by environmental changes forming barriers such as mountain building, changes in rivers, sea level change, climatic change or plate movements.

Question 10

Mass extinctions

Answer 10

have been caused by a combination of factors such as tectonic movements, super-volcanic eruption, climatic changes, and meteor impact all of which resulted in new directions in evolution and therefore increased biodiversity.

Question 11

Physical Barriers

Answer 11

When the same species, develops into two new species because of a physical barrier (e.g. mountain range or ocean)

Question 12

Land Bridges

Answer 12

Allow species to invade new areas

Result from lowering sea levels

Destroyed by continental drift

Question 13

Continental Drift

Answer 13

When continents move to different climatic zones

Food supply forces species to adapt to the new environment - increasing biodiversity

Question 14

Lithosphere

Answer 14

7 main plate boundaries that move 50-100 mm per year

Question 15

Where plates meet, they may…

Answer 15

Slide past each other

Diverge (this could cause the physical separation of populations)

Converge (Collide and both be forced upwards as mountains. This creates physical barriers // Collide and one sinks underneath lighter continental plate)

Question 16

Geological Timescale

Answer 16

4.6 billion years ago = Earth formed

4 billion years ago = Bacteria cells (thought to be first life forms)

65 million years ago = Dinosaur extinction

200,000 years ago = Humans

Question 17

Natural Extinction

Answer 17

1 species per 1 million species per year

Question 18

Causes of Extinction

Answer 18

Climate Change
Natural Disaster
Human Activities

Question 19

Adaptive Radiation

Answer 19

Species adapt to fill a niche but in turn leave one open

Question 20

Weedy Species

Answer 20

species that have adapted to survive in the newly created environments by humans

Question 21

Anthropogenic Extinction Causes

Answer 21

Transforming the environment

Overexploitation

Alien species introduction

Pollution

Question 22

Current extinction rate

Answer 22

100 species per million species per year

Question 23

Factors used to determine the conservation status of a species include:

Answer 23

• Population size
• Degree of specialization
• Distribution
• Reproductive potential and behaviour
• Geographic range and degree of fragmentation
• Quality of habitat
• Trophic level and the probability of extinction

Question 24

Complexity of the Ecosystem

Answer 24

The more complex a food web, the more resilient it is to the loss of one species or reduction in its population size.
If one type of prey or food source or predator is lost, the others will fill the gaps left.

Question 25

Inertia

Answer 25

the property of an ecosystem to resist change when subjected to a disruptive force.

Question 26

Natural Hazards

Answer 26

are naturally occurring events that may have a negative impact on the environment (and humans). Above a certain level the impact is so bad they are considered as natural disasters.

Question 27

Loss of Habitat

Answer 27

Major cause of loss of diversity. Humans have destroyed or changed most of the original natural habitat.

Question 28

Fragmentation of Habitat

Answer 28

the process whereby a large area is divided up into a patchwork of fragments, separated from each other by roads, factories, fences, power lines, pipelines or fields.

Question 29

Pollution

Answer 29

caused by human activities can degrade or destroy habitats and make them unsuitable to support the range of species that a pristine ecosystem can support.

Question 30

Introducing non-native (exotic/alien) species

Answer 30

can drastically upset a natural ecosystem. Humans have done this through colonization of different countries, bringing their own crops or livestock.

Question 31

Modern agricultural practices

Answer 31

reduce diversity with monocultures, genetic engineering and pesticides. Fewer and fewer species and varieties of species are grown commercially and more pest species are removed.

Question 32

Tropical Biomes

Answer 32

contain some of the most globally biodiverse areas and their unsustainable exploitation results in massive losses in biodiversity and their ability to perform globally important ecological services.

Question 33

Minimum viable population size

Answer 33

depends on so many factors such as genetic diversity in the individuals left, rate of reproduction, mortality rate, growth rate, threats to habitat and so on.

Question 34

Conservation Biology

Answer 34

the sustainable use and management of natural resources

Question 35

Preservation Biology

Answer 35

attempts to exclude human activity in areas where humans have not yet encroached

Question 36

Sustainable Development

Answer 36

meeting the needs of the present without negatively impacting the needs of future generations and biodiversity

Question 37

Intergovernmental Organizations (IGOs)

Answer 37

Composed of and answering to a group of member states (countries)

Also called international organizations

Question 38

Governmental Organizations (GOs)

Answer 38

Part of and funded by a national government

Highly bureaucratic

Research , regulation, monitoring and control activities

Question 39

Non-Governmental Organizations (NGOs)

Answer 39

Not part of a government

Not for profit

May be international or local and funded by altruists and subscriptions

Some run by volunteers

Very diverse