HL 1 Biology

5.5b Classification

<<Animal Classification>> Animals/plants: male + female gametes fuse together and zygote is formed = develops into embryo Animals: the embryo develops into a solid ball of cells and then into a hollow ball of cells (blastula) mouth, gut and anus + body systems (nervous/blood/skeletal systems) may develop then divided into over 30 phyla based on … Continue reading

HL 1 Biology

5.5a Classification

<<Classification>> Binomial nomenclature: naming organisms first name is the genus; a group of species that share certain characteristics second name is the species/specific name  Rules: genus name begins with a CAPITAL letter and species name with a lower-case letter in typed/printed text binomial is in italics after binomial is used once in the text , it can be abbreviated … Continue reading

HL 1 Biology

5.4c Examples of Evolution

<<Evolution in Action- Galápagos finches>> Darwin observed 14 different species of finches noticed they vary in sizes, shapes of beaks (as well as diet) Darwin’s hypothesis: “one might really fancy that from an original paucity of birds in this archipelago, one species had been taken and modified for different ends.” Darwin’s finches – relationship between … Continue reading

HL 1 Biology

5.3 Populations

182-184 <Population Growth> S-shaped, growth curve: represents what happens when a population colonizes a new habitat as pop. density increases, various density-dependent factors begin to limit pop. growth *limiting factors: competition for resources, toxic by-products of metabolism, increase in predation, increase in disease Transition phase: natality slows in relation to morality max size of  population … Continue reading

HL 1 Biology

5.4b Natural Selection

• AA-CC: 197-9 <<Natural Selection>> Charles Darwin: developed theory of natural selection took voyage around the world on HMS Beagle The Origin of Species: book he wrote explaining theory + evidence of natural selection OBSERVATION -> DEDUCTION overpopulation -> struggle for some individuals to survive, some go extinct  Adaption (variation) -> better adapted wil tend to survive … Continue reading

HL 1 Biology

5.4a Evidence of Evolution

AA-CC: 193-6 <<Evolution>> Evolution: the cumulative change in the heritable characteristics of a population Charles Darwin: proposed theory of natural selection Main types of evidence for evolution: breeding domesticated animals/ crop plants fossils homologous structures geographical distribution of animals/plants <<Evidence for Evolution>> Domesticated Animals humans breed particular animal species = more variation artificial selection: selecting … Continue reading

HL 1 Biology

5.2b Greenhouse Effect

AA-CC: 188-92   ================DBQ========================== Uncertainty in temperature rise projections (p.190) 1) AIFI 2) The minimum is 1.1 degrees Celsius,  Maximum 5.9 degrees Celsius 3) 1.8 degrees Celsius ( 4 – 2.2 = 1.8) 4) Comparing the forecasts for arctic temperature with those for global average temperatures, the temperature in the Arctic is higher than the global … Continue reading

HL 1 Biology

5.2a Carbon Cycle

Nutrients are recycled within an ecosystem are chemical elements: e.g. carbon, nitrogen, phosphorus Basic pattern of nutrient cycles: inorganic reserve of each element in the ecosystem consumers obtain the element in organic form by feeding on autotrophs/other consumers dead organic matter containing the element is released when organisms excrete waste material or they die Carbon … Continue reading

HL 1 Biology

5.1b Energy in Ecosystems

<<Energy Flow in Food Chains>> initial source of energy for most communities: light captured by plants through photosynthesis light converted to chemical energy in plants some used in cellular respiration, released as waste heat to the environment Energy stored in plant tissue passed on to next trophic level by primary consumers     ============DBQ========= A … Continue reading