Topic 4 Biodiversity Flashcards
Give three ways human activity is impacting biodiversity (with examples)
Pollution, causes certain species of plant and animal to die which reduces biodiversity.
Overhunting, causes certain animals to be removed from the food chain which reduces biodiversity.
Urbanisation / destruction of habitats. Causes entire ecosystems to be wiped out which has a massive effect on biodiversity in the area.
Give three reasons why humans should preserve biodiversity (with explanations)
For food, killing certain animals or plants would affect the entire food chain, and could damage our food sources.
For ethics, We damage biodiversity often, we should strive to not leave a negative effect on every aspect of the earth.
For aesthetics, Increased biodiversity creates a more vibrant and lush environment, which is much more pleasant to inhabit.
Define the term species
A species is a group of organisms that have similar morphology, physiology and can interbreed to produce fertile offspring.
Explain why understanding a species’ niche enables more successful conservation of that species.
Because it allows you to focus your efforts on preserving the species’ access to said niche, e.g. preserving honeybees by planting more flowers and not damaging beehives.
Definition of a species niche
The role a species plays in an environment, and the way a species exploits its environment.
Definition of a behavioural adaptation
An adaptation to a species’ actions to increase species survival, e.g a robin being territorial to prevent competition for food.
Definition of an anatomical adaptation
An adaptation to an organisms anatomy to increase species survival, e.g. a fly has many eyes to allow for hypersensitive 360degree vision.
Definition of a physiological adaptation
An adaptation to a species’ cell biology to increase species survival, e.g. zona pelucida hardening after a sperm cell breaches the cell membrane to prevent polyspermy.
State the 3 domains of classification
Prokaryote, Eukaryote, Archaea.
Explain what is meant by molecular phylogeny
Comparison of species’ DNA, mRNA and Proteins to determine how closely related they are to one another
Explain how molecular phylogeny enables organisms to be classified and evolutionary relationships to be identified.
It enables organisms to be classified by how similar they are physiologically, as their Proteins can be compared, also allows evolutionary relationships such as Converging, parallel or diverging evolution to be identified as species’ DNA can be compared with their behaviour and morphology.
What is meant by the term peer review
The process by which a panel of your scientific peers (People with similar qualifications in the same field) assess your work to make sure your scientific methodology is correct.
Explain how peer review enables the validity of findings to be established
Peer review allows for other people’s experience and findings to help verify the validity of your own results, as others may already have experience with similar research.
List how scientists can communicate their findings to the general public and to the scientific community.
To the general public: Speeches, news reports, advertisements.
To the scientific community:
Scientific journals, conferences.
Give the 5 conditions the Hardy-Weinburg formula is dependent upon
- Large population
- no immigration or migration
- no mutations
- mating is random
- no natural selection
Explain why the H-W formula cannot be used for sex-linked conditions (hint: consider the XY chromosomes)
Because males carry xy combination of chromosomes, they only have one allele
Give the two formulas needed for Hardy-Weinburg calculations and provide a key
p^2 + 2pq + q^2 = 1.0
p + q = 1.0
p = frequency of dominant allele
q = frequency of the recessive allele
Explain how reproductive isolation can result in speciation (the formation of new species)
Because the different isolated populations will have different mutations and be exposed to different selection pressures, and therefore will evolve in different ways.
Define biodiversity
Biodiversity is the number and distribution of different organisms inside a community of organisms.
Define the term endemic
An endemic species is a species which is only found in one habitat.
Give the formula for heterozygosity index
2pq
Explain how heterozygosity index gives a measure of biodiversity
It shows how varied a species’ gene pool is, which gives an indication of how diverse the species is.
Define the term species richness
The number of different species in a habitat
Define the term species evenness
The distribution of organisms within different species ( Higher species evenness = more evenly spread distribution of organisms)
List the four roles of a zoo
Scientific research about ecology/breeding behaviour
Captive breeding programmes
Reintroduce animals into the wild
Educate the general public
Define the term genetic drift
Occurs in a small, closed population.
Some alleles are not passed on through chance which leads to a reduction in the gene pool (fewer alleles in the population) which makes the population at greater risk of extinction if environment changes
Define the term inbreeding depression
Occurs in small, closed populations.
In small populations there are a limited number of sexually mature adults, therefore increasing the likelihood of closely related individuals breeding, which causes homozygous recessive genotypes to be passed down, which is often harmful in offspring as this genotype often carries disease.
Explain how studbooks avoid genetic drift and inbreeding depression in captive bred populations
Keeps track of who is related to who, stops them from breeding together, Keeps track of where animals came from, If animals are closely related or have similar genotypes to their current captive population they are transported to other captive bred populations to increase genetic diversity.
Explain the conditions needed in order to store seeds in seedbanks
Cold: reduces enzyme activity to prevent germination, prevents decat
Dry: to prevent damage via ice crystal formation (freezing effect)
These factors protect viability and longevity.
Explain why seeds need to be tested for viability
to deduce the quality of seeds, to determine the efficacy of seed storage and to help plant the proper amount of seeds
Give reasons why storage of seeds is useful from a conservation standpoint
Allows for reintroduction of endangered populations into the wild,
preserves genetic diversity to prevent genetic drift in small populations,
Compare and contrast the structure of starch with cellulose
Starch: made of 2 polymers,
Made of alpha glucose,
1,4,6 glycosidic bonds
Cellulose:
Made of one polymer,
H bonds between chains,
Beta glucose,
1,4 glycosidic bonds
Both:
Polymer chains made via condensation reaction
State the stages involved in a clinical trial and give a reason for each stage
Stage 1: Animal trial to test safety / toxicity of drug
Stage 2: Test on small group of healthy volunteers to test for side effects
Stage 3: Test on small group of diseased individuals to confirm efficacy of drug and to find correct doseage,
Stage 4: Double blind trial on large group of diseased individuals to test efficacy without placebo or bias.
Stage 5: Post clinical trials to find long term side effects of drug
Compare and contrast the modern clinical trial procedure with the William Withering procedure
Both involve treating diseased patients with the drug to establish if it is effective at fighting the disease. Modern trial involves testing on animals first to confirm safety, william withering trial does not. Modern trial tests for placebo effect, william withering trial does not. Both involve slowly increasing dosage until side effects are seen to find correct dosage.
Explain what is meant by a double blind trial and why it is necessary
A double blind trial is where both the drug takers and administers do not know which is a placebo drug and which is a real drug, and it is used to establish how much of a role the placebo effect plays in the treatment of the disease.
Explain what is meant by placebo and why it is necessary
Placebo effect is a psychological reaction where the brain thinks it is receiving treatment which causes the body to stop reacting to the disease in the same way, essentially treating the disease.
