Unit 2 - Module 3 - Biodiversity And Evolution Flashcards
(109 cards)
0
Q
Define habitat
A
The place where an organism lives
1
Q
Define species
A
A group of individual organisms very similar in appearance, anatomy, physiology, biochemistry and genetics, whose members are able to interbreed freely to produce fertile offspring
2
Q
Define biodiversity
A
The variety of life.
It include all the different plant, animal, fungus and microorganism species worldwild, the genes they contain and the ecosystems of which they are a part.
3
Q
Why can biodiversity be considered on a level of habitats?
A
In an area there are many different habitats, for example in woods, there are trees, rivers, the ground etc.
4
Q
How can biodiversity. Be considered in a species level?
A
All species are different from each other.
Could be obvious structural difference or functional difference.
5
Q
How can biodiversity be considered on a genetic level?
A
Variation between individuals belonging to same species.
6
Q
Why cannot we be sure how accurate estimates on global biodiversity are?
A
Cannot be sure we have found all the species
New species are being found all the time
Evolution and speciation are continuing
Many species are endangered and some are becoming extinct
7
Q
How many species is it estimated there are?
A
1800 000
8
Q
How can you randomly choose the position of you sample sites inside a habitat?
A
Take sample at regular distances across the habitat
Use random numbers, generated by a computer to plot coordinates within the habitat
Select coordinates from a map of the area and use a portable Global Positioning System to find exact position inside the habitat
9
Q
What is a quadrat and what is it used for?
A
A square frame used to determine the size of the sample area.
10
Q
How do you use a quadrat?
A
Place it at random in the habitat.
Identify the plants found within the frame
Measure the abundance of the plants
11
Q
How can you measure abundance of plants?
A
An abundance scale. Estimates abundance most common is ACFOR scale. Observe contents and apply scale to each species
Estimate percentage cover.
12
Q
How can you estimate percentage abundance with a point frame?
A
Lower frame into quadrant record any plant touching the needles.
If it has 10 needle and is used 10 times. Each plant touching the needle will have 1% cover.
13
Q
Why can you have a percentage cover of more than 100%?
A
One needs may touch several plants
14
Q
What is a transect?
A
A line taken across the habitat.
Stretch a long rope or tape measure across the habitat and take sample along it.
15
Q
What is an interrupted belt transect?
A
Use transect. Record plants touching the line at set interval along it.
Use quadrat at set intervals along the line.
16
Q
What is a continuous belt transect?
A
Place a quadrat beside the line, and move it along the belt so you can study a band or belt in detail
17
Q
How can you catch animals?
A
Sweep netting Collecting from trees A pitfall trap A Tullgren funnel A light trap
18
Q
What is sweep netting?
A
It involves waking through a habitat with a stout net.
Sweep the net through the vegetation in wide arcs.
Any small animals will be caught in the net
Can empty the net into a white sheet to identify them
19
Q
What is a pooter?
A
A device that is used to collect animals before they fly away
20
Q
How can you collect from trees?
A
Spread a white sheet under a branch and knock it with a stout stick.
Vibrations caused dislodge and small animals, which then drop onto the sheet.
21
Q
What is a pitfall trap?
A
A trap set in soil to catch small animals.
Consists of a small container buried in the soil so that it’s rim is just below the surface.
22
Q
What is a Tullgren funnel?
A
A device for collecting small animals from leaf litter.
Place leaf litter in a funnel, the light above drives the animals downwards.
Fall through mesh to be collected in jar underneath the funnel
23
Q
What is a light trap?
A
Consists of an ultraviolet light that attracts insects. Under the light there is a collecting vessel containing alcohol.
24
Why do we need to study a habitat?
Human activities affect the environment in a number of ways
Unless we study how our activities affect our environment, we cannot asses the effect we have.
EIA is used to estimate the effect of planned development
Sp we do not lose habitats or biodiversity.
25
How can we estimate species richness?
A qualitative survey
| Take samples
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How can we estimate the frequency of plants?
Use sampling techniques
| Count number of plan te of each species per unit area, or measu percentage cover
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How can you measure density of large animals?
Observe carefully and count the individual present
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How can you measur the density of smaller animals?
Take samples
| Mark and recapture technique
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What is the mark and recapture technique?
Capture and mark a sample of animals. The number captured will be C1 .
Release them and leave the traps
Number captured second time will be C2
Number if already marks animals will be C3.
Total population = (C1 X C2) / C3
30
What does a high value of Simpson's index indicate?
A diverse habitat.
| Habitat tends to be stages and withstand change
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What does a low value for diversity indicate?
A habitat dominated by a few species.
| A small change could damage or destroy the whole habitat
32
Define biological classification?
The process of sorting living things into groups.
Natural classification does this by grouping things according to how closely related they are
It reflects evolutionary relationships
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Define taxonomy
The study if the principles behind classification
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Define phylogeny
The study of the evolutionary relationships between organisms
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What are the five kingdoms?
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Prokaryota
Protocista
Fungi
Plantae
Animalia
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Prokaryotes
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No nucleus
A loop of naked DNA
No membrane bound organelles
Smaller ribosomes
Carry out respiration not in mitochondria but on mesons ones
Smaller than eukaryote cells
May be free living or parasitic
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Protocists
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Eukaryotes
Mostly single cells
Wide variety of forms
Plant like or animal like features
Mostly free living
Autotrophic or heterotrophic nutrition
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Fungi
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Eukaryotes
Have a mycelium which consists of hyphae
Walls of chitin
Multinucleate
Mostly free living and saprophytic
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Plants
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Eukaryotes
Multicellular
Cellulose cell wall
Produce multicellular embryos from fertilised eggs
Autotrophic nutrition
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Animals
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Eukaryotes
Multicellular
Heterotrophic nutrition
Fertilised eggs that develop into a blastula
Usually able to move around
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Why do we classify things?
Convenience
To make study more manageable
Easier to identify organisms
Help use see relationship between species
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What are the eight taxa in order?
```
Domain
Kingdom
Phylum
Class
Order
Family
Genus
Species
```
43
What are the three domains?
Bacteria (Eubacteria)
Archaea (Archaeabacteria)
Eukaryotes
44
Why does using a common name not work?
Same organism may have completely different common name in different parts of one country
Different common names are used in different countries
Same common name may be used for different species in other parts of the world.
45
Define binomial system
It uses two name to identify each species
The genus name (capital first letter)
Species name
UNDERLINE IT
46
Define dichotomous key
A series of question with two alternative answers to help identify a species
47
Briefly describe a EIA
An environment impact assessment
What species are present in the area
If there are any very rare species, then losing that habitat would have a major impact
48
How did Aristotle classify living things?
```
If they were animal or plant
He divided the animals into three group:
Live and move in water
Live and move on land
Move through the air
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49
What structural differences do bacteria and archaea have?
Bacteria:
Different cell membrane structure
Flagella with different internet structures
Different enzymes for building RNA
No proteins bound to their genetic material
Different mechanisms for DNA replication and for building RNA
50
How are archaea similar to eukaryotes?
Similar enzymes for building RNA
Similar mechanisms for DNA replication and building RNA
Production of some proteins that bind to their DNA
51
How does cytochrome c show how closely related species are?
If the amino acid sequences are the same, the two species must be closely resulted
If they are different, two species are not closely related
The more difference between sequence ps the less closely related the two species.
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What is cytochrome c?
A proteins that is used in respiration.
All living organism Exocet chemosynthetic prokaryotes have it
Not identical in all species
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Define variation
The presence of variety of differences between individuals
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Define genetic variation
Caused by difference between the genes and combinations of genes or alleles
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Define continuous variation.
Variation in which the is a full range of intermediate phenotypes between to a extremes
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What are some examples of continuous variation?
Height in humans
Length of an oak leaf
Length of a stalk of a toadstool
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Define discontinuous variation?
Variation in which there are discrete groups of phenotypes with no or or very few individual in between
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What are some examples of discontinuous variation?
Sex - mammals are either male or female; plants are either male, femal or hermaphrodite
Some bacteria have flagella others do not
Human blood group - you are blood group A, B, AB or O
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What are the causes of variation?
Inherited or genetic
| Environmental
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What is inherited or genetic variation?
Combination of alleles that we inherit is not the same as that of any other living thing.
Combination is unique
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What we environment causes of variation?
Nutrition
Sunlight
Wind
Etc
62
Define adaption
A feature that enhances survival and long term reproduction success
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What will a well adapted organism be able to do?
Find enough food or photosynthesis well
Find enough water
Gather enough nutrients
Defend its self from predator and diseases
Survive physical conditions of its environment
Respond to changes in its environment
Still have energy left over to reproduce successfully
64
What are behavioural adaptations?
An aspect of the behaviour of an organism that helps it to survive the condition it lives in.
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What is an example of a behavioural adaptation?
When you tough an earthworm it quickly contracts and withdraw into its burrow
Adaptation to avoid being eaten
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What I pare physiological/biochemical adaptations?
One that ensures the correct functioning if cells processes
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What is an example of physiological/biochemical adaptation?
Yeast can respir anaerobic sky or aerobic all to obtain energy, depending in how much oxygen there is in its environment.
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What are anatomical adaptions?
Structural
| Any structure that enhance the survival of the organism
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What is an example of an anatomical adaption?
Many bacteria have flagella that enable them to move independently.
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What are the behavioural adaptations of xerophytic plants?
Close their stomata when little water is available
Only open their stomata at night
Fold or roll their leaves
Open their stomata when they are short of water. They wilt and expose less surface area
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What are physiological/biochemical adaptations of xerophytic plants?
The mechanism by which a plant can open or close its stomata, fold its leaves or store water.
72
What are the anatomical adaptions of xerophytic plants?
Shallow roots but spread over a wide area
Very long roots
Sten or leaves may be fleshy
Leaves may be reduced in size
The leaves may be waxy
Th leaves may be curled, folded or hairy or have stomata sunken in pits.
73
What observations did Darwin make?
Offspring generally appear similar to their parents
No two individuals are identical
Organism have the ability to produce large numbers of offspring
Populations in nature tend to remain fairly stable in size.
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What are Darwin's conclusions?
There is a struggle to survive
Better adapted individual ps survive and pass on their characteristic
Over time, a number of changes may give rise to a new species.
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What are example of factor that act as selective forces?
Availability of chose food
Predators
Diseases
Physical and chemical factors
76
Define natural selection
The selection by the environment of particular individuals that show certain variations. These individuals will survive to reproduce and pass on their variations to the next generation
77
Define speciation
Th formation of a new species
78
How long does speciation take?
It is a long slow accumulation of changes.
| Takes many generations
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How does speciation occur?
There must be a reproductive barrier. This means that some organisms are unable to breed with others in the group.
A collection of small changes that cannot pass to the whole groups means that some members become different from the others.
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What is allopatric speciation?
It is where a geographical separation prevents effective interbreeding between individuals of two populations. Over time the populations become so different that they cannot interbreed and are considered to be two different species.
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What is sympatric speciation?
Speciation that occurs within one area some factor other than geographical separation has prevented free interbreeding between members if the species.
May be a behavioural change - courtship dance not recognised
Physical change - sexual organs no longer compatible cannot mate
82
In Darwin's time what dis fossils show?
In the past the world has been inhabited by species that were different from those present today
Old species have died out
New species have arisen
New species are similar to older ones
83
Brachiopods ans Darwin
Their fossils appeared in rocks formed over a long period of
They changed slowly over time
The rocks from different eras contained their own characteristic species of brachiopod,
Could be used to determine relative age of rocks
84
Armadillos and Glyptodonts
Very similar apart from older were much larger
85
What recent fossil evidence is there?
Evolution if modern horse is well documented in fossil record
Evolution of humans can be seen in series of fossils lo dating back 3-4 million years, but the are many gaps
Links between mayor groups. E,g, fossil of one of the earliest birds shows many features typical of reptiles.
86
What is the problem with fossil evidence?
It is incomplete
Only hard parts become fossil
Only form under certain condition
Once formed can still be damaged or destroyed
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What evidence is there from biological molecules?
Certain molecules are found throughout the living world. Suggests all species rose from a common ancestor
Two closely related species will have evolved recently as separate species. Molecules likely to be identical or very similar
Different evolutionary paths, molecules likely to differ
Cytochrome c and other proteins show pattern change
88
How does evolution work?
Variation must occur
Once variety exists, environment can select. Select advantageous.
Individual with an advantage will survive and reproduce
Pass on advantageous characterises
Next generation will be better adapted.
89
Why do new species occur?
A population migrates to a new environment
An environmental change affect only some population it the species
There is a reproductive barrier preventing interbreeding
90
How has human society developed?
```
Learned to use environments to our advantage
Our numbers have risen dramatically
Using more and more of Earth's resources
Activities harm other species
Loss of biodiversity
Extinction
```
91
Statistics on extinction
784 recorded extinction since 1500
Up to 20% of species alive today could be extinct by 2030
A third if the worlds primates face extinction
Some believe up to half of species alive could be extinct by 2100
Current rate is 100-1000 times faster than normal background rate
At least as fast as in any precious extinction event
92
What human activities reduce biodiversity?
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Hunting for food
Killing for protection
Killing to remove competitors for food
Pollution
Habitat destruction
Inadvertent introduction of new predators and competitors
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93
What economic and ecological reasons are there to conserve species?
Provide answers to problems, we may lose this ability
| Lose the ability to find new medicines
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What ethical and aesthetic reasons are ther to conserve species!
All living organisms have a right it survive and to live in a way for which that have become adapted
Joy/well being
Patients recover more quickly when exposed to pleasing natural environment conditions
95
What threats to species with low genetic diversity are there?
Change in climate
Increase in levels of pollution
Emergence of new disease
Arrival of new pests
96
What must species do if they have lost their genetic variation as climat changes?
They will have to migrate
| Towards the poles
97
What obstructions are there to migration?
Major human developments
Agricultural lands
Large bodies of water
Humans
98
How will climate change affect agriculture?
High carbon dioxide levels altering photosynthesis
High temperatures increasing growth rates
Longer growing seasons
Greater evaporation of water and therefore greater precipitation
A change in the distribution of precipitation
Loss of land due to rise in sea level and increases salinity of the soil
99
Why are domesticated plants and animals particularly at risk?
We have selectively bred them so they have little variation
They will be unable to devolve and adapt to changing environment.
Also they will encounter new diseases and pests will not have resistance.
100
How will climate change affect disease in humans?
They will migrate.
Tropical diseases may become a problem in Europe
Anopheles mosquito may live in new areas
101
Define conservation in situ?
Conserving a species in it normal environment.
| Attempting to minimise human impact and protecting the natural environment.
102
What are the advantages of conservation in situ?
Conserved in natural environment
Permanently protects biodiversity and representative ecosystems
Permanently protects elements if natural and cultural heritage
Allows management to ensure ecological integrity is maintained
Provides opportunities for ecologically sustainable land uses
Facilitates scientific research
Possible to restore the ecological integrity of the area
103
What must the principles of choosing a reserve or park include?
Comprehensiveness - how many species
Adequacy- is it large enough
Representativeness - full range of diversity
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What conflicts arise from in situ conservation?
Protected animals coming out of the reserve to raid crops
People continuing to hunt protect animals
Illegal harvesting if timber and other plant products
Tourists feeding protected animals or leaving littere
105
Define conservation ex situ
Conserving an endangered species baby activities that take place outside its normal environment
106
What advantage are there of conserving animal species ex situ?
Can increase numbers if individuals
| Can enable repopulation by introducing deprive bred animals to the wild
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What are the disadvantages of conserving animals species ex situ
Not in natural environment and may fail to breed properly
Space is limited and this limits numbers, which restricts genetic diversity - lack of variation
Species less able to adapt to changing conditions
Have to survive reintroduction, need to find food and survive predation
Also difficulties with acceptance by wild animals
108
What modern techniques make it possible to preserve large
Sperm freezing, artificial insemination, in vitro fertilisation and embryo transfer techniques can bed used
Reproductive physiology research is needed to make sure techniques are used effectively
