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Infection and response
Organisation
Cell biology
Biological molecules
Homeostasis and response
Responding to change (a2 only)
Energy transfers (a2 only)
The control of gene expression (a-level only)
Substance exchange
Bioenergetics
Genetic information & variation
Inheritance, variation and evolution
Genetics & ecosystems (a2 only)
Ecology
Cells
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1f industrialisation and the people: britain, c1783-1885
1c the tudors: england, 1485-1603
Britain & the wider world: 1745 -1901
Inter-war germany
World war one
2n revolution and dictatorship: russia, 1917-1953
World war two & the holocaust
1l the quest for political stability: germany, 1871-1991
The cold war
2j america: a nation divided, c1845-1877
Medieval period: 1066 -1509
The fight for female suffrage
2m wars and welfare: britain in transition, 1906-1957
2d religious conflict and the church in england, c1529-c1570
Britain: 1509 -1745
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26/03/2023
1953
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BIODIVERSITY BIODIVERSITY is the variety of living organisms. Human impacts are now threatening the biodiversity of some of our most delicate ecosystems. Biodiversity can be measured in many ways, including: species richness, species evenness, genetic diversity and the index of diversity where a particular pattern is followed (e.g. sample every 5 meters) Systematic Sampling ✓ eg transect squares SAMPLING METHODS Data/sample taken when a source (organism) is encountered. Opportunistic- Sampling Based off of ease of access Random Sampling D = N(N-1) [n(n-1) This obtains a representitive sample. of the area under investigation The Index of Diversity N= Total no. of organisms total no. of norganisms per species Random samples of Strata taken in Stratified i comparison to size of species populations Sampling Method of sampling where. populations are devided into smaller groups (strata) based off of common characteristics Why Is Biodiversity important? Maintaining and protecting biodiversity is important for ecological, economic and aesthetic reasons. Ecological maintains equillibrium in ecosystems and food chains/webs. Economic~ ecotourism industry + new discoveries of medicinal plants Aesthetic Protecting landscapes + views of wild life. COBIOSFERSITING • Insitu methods such as wildlife reserves + marine conservation zones which aim to protect the wildlife within that area/habitat. •EX situ conservation includes zoos, seed banks and botanical gardens, these protect the Wildlife by removing them from their natural, wild nabitat. • Zoos use various methools to conserve endangered species and their genetic diversity ↳ Scientific Research ~e.g. studying behaviour, working on breeding success to increase population size, and controlling/erradicating diseases. Captive breeding programmes ~ endangered species carefully bred to increase geretic diversity and population size Reintroduction programmes which aim to release individuals that were bored...
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in captivity into their natural habitat as well as to restore loss of habitat. > Education Programmes ~ aim to educate people about the importance of maintaining biodiversity, captive breeding programmes, and the illegal trade of animals and animal products. . • Seed banks store a large number of seeds in order to conserve genetic diversity and prevent plant species from going extinct. Storing seeds instead of plants means that a larger variety of species can be conserved - it's also cheaper than storing plants as it's much more space effective. The seeds are stored in cool, dry conditions as this maximises the length of time that they can be stored for." • Biodiversity conservation requires international coorperation. These are historic and current agreements, including the conservation of International Trade in Endangered species (CITES), the Rio Convention on Biological Diversity (RBD) and the Countryside Stewardship Scheme (css) CLASSIFICATION Kingdom e.g. Animal Phylum Chordates. Class & Mammals ↓ Order Primates Family Hominids Genus Homo ✓ ↓ Species Homo Sapians > Classification is the process of naming and organising organisms into similar characteristics. There are 5 kingdoms (animalio, plante, fungi, prokaryotes + protoktists). They are then grouped further. Each species is named due to the binomial system (first-genus, second-species) > Analysis of molecular differences in different organisms to determine the extent of relation is known as molecular phyloney. This gave rise to taxonomic groupings (bacteria, eukaryotes and Archaea). Exam Tip ~ When remembering the order of Classification it might help to create an anogram. Whe: King Phillip Came Over For Good Soup. EVOLUTION. > Organisms are adapted to their environment. in 3 main ways: Anatomical adaptions ~ physical adaptions (e.g. change in loop of henie dependanton water availability. Behavioural adaptions ~ changes in behaviour (e-g mating calls). ↳ Physiological adaptions ~ changes to processes inside an organism's body that increase the chance of survival (eg blood flow regulation). NATURAL SELECTION H Natural selection is the process of which fitter individuals who are better adapted survive and so pass on their advantageous genes to their offspring. This increases the frequency of the best genes in the population. Evolution via natural selection: 1.A variety of phenotypes within a population. 2. Environmental change causes selection pressures to change 3. Individuals who posess advantageous genes live on. 4. Advantageous alleles are passed to offspring 5. Frequency of these alleles in a population increases If two populations become reproductively isolated, new species will be formed due to accumulation of different genetic information in populations over time due to different environments + selection pressures. >observations - Charles Darwin many other scientists have provided evidence for evolution. Darwin observed finches on the Is Galapagus. EVIDENCE FOR EVOLUTION >Fossils remains of extinct organisms and comparing them to those in the present. 2 >Molecular Biology-looking at similarities + differences between ONA sequences of different organisms >Comparative Anatomy-comparing the anatomy of organisms. ·Variation. • Each population shows natural variation in continuous or discontinuous ways Discontinuous- no intermediates. These are represented as barcharts $mostly controlled by one gene (e-geye colour) Continuous - characteristics that can take any value. Represented by histograms. Usually show a normal distribution. Controlled by multiple genes B influenced by the environment (eg. neight or weight).