Biodiversity Flashcards
What’s biodiversity?
Variety of organsims
What’s species diversity?
Number of different species and the abundance of each species in an area
What’s genetic diversity?
Variation of alleles within a species
What’s endemism?
Species is unique to a single place
What’s natural selection?
Leading to adaptation and evolution that has increase biodiversity over time
What’s conservation?
Needed to help maintain biodiversity
What’s a habitat?
Place where an organism lives
How can you measure species diversity?
Count number of different species in area
Higher species greater sources richness
Count number of different species and number of individuals in each species
Use index of diversity to calculate species diversity
How to calculate species diversity ?
Choose small area to sample
Count number of individuals of each species in sample area
Plants - quadrant
Flying insects - sweepnet
Insects - pitfall trap
Aquatic animals - net
Repeat process
Use results to estimate Tortola Humber of individuals in habitat being studied
What’s genetic diversity?
Variety of alleles in the gene pool of a species or population
What’s a gene pool?
Complete set of alleles in a species or population
What 2 things do you look at to measure genetic diversity?
Phenotype and genotype
What’s a phenotype?
Observational characteristics of an organism
What’s a genotype?
What does heterozygosity index measure and what’s the equation?
Genetic diversity
Number of heterozygotes / number of individuals in the population
How can biodiversity be measured and what’s the equation?
Index of diversity
D = N(N-1) / ßn(n-1)
N is the total number of organisms of all species
n is the total number of organisms of one species
ß is sum of
What’s a niche?
Role of a species within its habitat
What happened if 2 species type to occupy the same niche?
They’ll compete with each other
How many species can occupy a niche?
Only 1
What are the 3 ways that organisms can be adapted to their niche?
Behavioural adaptations
Physiological adaptations
Anatomical adaptations
What’s a behavioural adaptation?
Ways an organism acts that increase its chance of survival
e.g. some organisms dance to attract mates
What’s a physiological adaptations?
Processes inside an organisms body that increase its chance of survival
e.g. hibernations to lower rate of metabolism
What’s an anatomical adaptation?
Structural features of an organisms body that increase its chance of survival
e.g. whales have a thicker layer of fat to keep them warm
How do adaptations become more common?
By evolution
What is selection pressure and give an example?
Anything that affects an organisms chance of survival e.g. predation, disease and competition
What does an advantageous allele do?
Ensures the organism can survive for longer
Name the process how adaptations become more common by evolution…
Mutations introduce new alleles into a population so individuals in that population show variation in their phenotypes
Some alleles determine characteristics that can make the individual more likely to survive
Selection pressures create struggle for survival
Individuals without advantageous allele done survive
Individuals with advantageous allele are more likely to survive and reproduce
Advantageous allele is passed on to offspring
Over time number of individuals with advantageous allele increases
Over generations this leads to evolution as frequency of advantageous allele becomes more common
Who can up with the theory of evolution by natural selection?
Charles Darwin
What’s the peppered moth theory?
They show variation in colour due to a mutation in gene
There were more light than dark moths
Pollution had blackened many trees
Dark moths were no better adapted to environment due to having the advantageous allele meaning they could camouflage
Light coloured moths were more susceptible to predation therefore dark moths had less competition
Dark moths could survive longer and reproduce and pass on allele to offspring
Over time frequency of alleles increased and dark moths became more common
What is speciation?
Development of a new species
What is a species
Organisms capable of interbreeding and can produce fertile offspring
When does speciation occur?
Populations of the same species become reproductively isolated
What are the changes that can cause speciation?
Seasonal - individuals from same population develop different mating seasons
Mechanical - changes in genitalia prevent successful mating
Behavioural - group of individuals develop courtship rituals that aren’t attractive in main population
What can geographical isolation lead to?
Speciation
When does geographical isolation occur?
- Physical barrier divides a population of a species
- Conditions on either side of barrier will be different
- As environment is different on each side different characteristics will become more common due to natural selection
- eventually different populations will become genetically distinct (they’ll have become reproductively isolated)
- 2 groups will have become separate species
What is evolution?
A change in allele frequency
How are new alleles usually generated?
By mutations
How can allele frequencies be calculated?
Using the hardy-Weinberg equation
What is the hardy-Weinberg equation?
P2+2PQ+Q2=1/100%
What does P2 stand for?
Frequency of homozygous dominant genotype
What does 2PQ stand for?
Frequency of heterozygous genotype
What does Q2 stand for?
Frequency of homozygous recessive genotype
What does P stand for?
Frequency of dominant allele
What does Q stand for?
Frequency of recessive allele
What do allele frequencies show?
If a population is changing overtime
What is classification?
Placing organisms into groups on the shared characteristics
What is the groups in the classification system?
Domain
Kingdom
Phylum
Class
Order
Family
Genus
Species
What happens when you go down the hierarchy of the classification system?
There are more groups but fewer organisms in each group
What is the name of the naming system and who invented it?
Binomial
Carl Linnaeus
What is the classification system based on?
Phenotypes genotypes and how related they are
What new technologies have been used to enable organisms genotypes?
looking at DNA sequences
What are the 5 kingdoms that organisms can be placed in?
Animal
Plant
Prokaryote
Fungi
Protist
What is an example of animal kingdom and some features?
Heterotroph
Cannot produce its own food
What’s an example of plant kingdom and some features?
A type of plant
It has a cellulose cell wall
What’s an example of a prokaryote kingdom and some features?
Peptidoglycan cell wall
What’s an example of fungi kingdom and some features?
Chitin cell wall and digests outside of it
What’s an example of protist kingdom and some features?
It has no cell wall
(Also known as protoctista)
What are 2 example of phylum?
Vertebrates and invertebrates
(Part of the animal kingdom)
What are the 5 examples of class?
Birds
Fish
Mammals
Amphibians
Reptiles
What’s a feature that makes birds distinctive?
Feathers
What’s a feature that makes fish distinctive?
Wet scales (produce slime that helps reduce friction)
What’s a feature that makes mammals distinctive?
Fur/hair
Give birth to live young
Produce milk
What’s a feature that makes amphibians distinctive?
Lay eggs in water
Have moist permeable skin
What’s a feature that makes reptiles distinctive?
Dry scales
Lay eggs on land
What are the classification systems names?
Domain
Kingdom
Phylum
Class
Order
Family
Genus
Species
What happens as you move down the hierarchy of the system?
More groups but fewer organism
What are the classifications of organisms based on?
Genotype
Phenotype
How related they are
What’s the 2 word naming system called and who created it?
Binomial
Carl Linnaeus
What is convergent evolution?
Unrelated organisms that have evolved to look more similar
Why is convergent evolution problematic for classification and what technology do we have to overcome this?
They could be incorrectly classified as the same family/genus because they look similar
DNA technology and check sequence of amino acids for level of similarity
What did Carl Woese discover?
Made a discovery in a lake which was a brand new organism but organisms didn’t fit into any of car Linnaeus kingdoms
He looked at the DNA of the organisms and it wasn’t the same as other prokaryotes DNA
He added the Domain above kingdoms and it was split into 3: bacteria, archae, eukarya
Kingdoms then change depending on the domain
What is an example of Archae?
Extremophiles
What do zoos and seed banks do?
Help conserve endangered species
What does extinction or loss of genetic diversity cause?
Reduction in global diversity
What do seedbanks store?
Seeds from plants that are endangered
What does the work of seedbanks involve?
Creating cool dry conditions needed for storage (seeds can be stored for a long time)
Testing seeds is needed for viability (ability to grow into a plant)
What are some advantages of a seedbank?
Cheaper to store seeds than fully grown plants
Less labour required to look after seeds than plants
Seeds are less likely to be damaged by disease or vandalism than plants
What are some disadvantages of seedbanks?
Testing viability can be expensive and time consuming
Too expensive to store all types of seeds and regularly test their viability
Difficult to collect seeds as they may grow in remote locations
What programmes do zoos have to help endangered species?
Captive breeding programmes
What can species do in the zoo to help increase their numbers?
Be bred together
What are some problems with captive breeding programmes?
Animals can have problems breeding outside their natural habitat
Some people think it’s cruel to keep animals in captive even if it’s done to prevent them coming extinct
Why and how can organisms from zoos and seedbanks be reintroduced to the wild?
Reintroduction of plants/animals from seedbanks and zoos can increase their number sun the Wild
Bring them back from brink of extinction
Restoring loss habitats
What are some problems caused by reintroduction of animals and seeds into the wild?
Could bring new diseases into habitats harming other organisms
May not behave as the would if they had been raised in the wild
How do seedbanks contribute to scientific research?
How plant species have been successfully grown from seeds
Used to grow endangered species for use in medical research
How can zoos contribute to scientific research?
Increases knowledge about behaviour physiology and nutritional needs of animals
Carry out research that’s not possible in the wild
What are the assumptions of the hardy Weinberg principle?
Population size is infinite
There are no mutations migration or emigration
There is no selective pressure
Why is the index of diversity a better measurement than species richness?
It takes into account both the number of species and their relative abundance
What’s the definition of species richness?
Number of species in a habitat or community
