SCIENCE

• Kepler's Laws of Planetary Motion


  The orbit of a planet is an ellipse with the Sun at one of the two foci<|>A line segment joining a planet and the Sun sweeps out equal areas during equal intervals of time<|>The square of the orbital period of a planet is proportional to the cube of the semi-major axis of its orbit
• Classification of Rocks


  • Igneous: forms from cooled magma or lava
  • Sedimentary: Erosion from water and weather carries deposits downstream which will form layers
  • Metamorphic: Form when other types of rocks undergo extreme heat, pressure and chemical processes deep in Earth's crust
• Igneous rocks


  • Intrusive igneous rock (ex. granite) - forms in underground pockets
  • Extrusive igneous rock (ex. obsidian) - forms above ground
• Sedimentary rocks


  • Clastic sedimentary rocks (ex. sandstone) - formed from inorganic debris
  • Organic sedimentary rocks (ex. limestone or coal) - formed from plant or animal remains
  • Chemical sedimentary rock (ex. rock salt) - formed when dissolved materials come out of solution
• Metamorphic rocks


  • Foliated metamorphic rocks (ex. slate) form with visible layers or banded striations from pressure
  • Non-foliated metamorphic rocks (ex. marble ) form more irregular striations
• Rock Cycle


  1. Igneous and sedimentary rock -> metamorphic rock: high pressure and heat

  2. Sedimentary and metamorphic rock -> igneous rock: melting back into magma

  3. Igneous and metamorphic rock -> sedimentary rock: erosion
• Elements on the Earth's Crust

  • Oxygen
  • Silicon
  • Aluminum
  • Iron
  • Calcium
  • Sodium
  • Potassium
  • Magnesium
  • All other elements
• Minerals


  Substances formed naturally in the Earth with definite chemical composition and structure
• Types of Weathering


  • Mechanical weathering: Fracturing, Abrasion
  • Chemical weathering
  • Biological weathering
• The most common product of chemical weathering is clay
• Layers of Soil
• Mohs' Scale of Hardness
• Crust


  • Continental crust – make up land masses, 32-70km thick
  • Oceanic crust – make up ocean floor, 8km thick
• Types of Stress


  • Compression
  • Tension
  • Shearing
• Types of Faults


  • Normal fault
  • Reverse fault
  • Thrust fault
  • Lateral Strike Slip fault
• Plate tectonics


  The Earth's surface is made up of a series of large plates (like pieces of a jigsaw puzzle) which are in constant motion travelling at a few cms per year, spreading from the centre and sinking at the edges, termed as convection currents sourced from radioactive decay of Earth
• Continental Drift


  • Theory that continents can drift from one another
  • Alfred Wegener said that "From supercontinent named Pangea continents moved, the leading edge of the continent would encounter resistance and thus compress and fold upwards forming mountains near the leading edges of the drifting continents"
• Types of Plate Boundaries

  • Transform boundaries
  • Divergent boundaries
  • Convergent boundaries
  • Plate boundary zones
• Half-life


  The amount of time required for a quantity to fall to half its value as measured at the beginning of the time period
• Steps of Scientific Method

  • Observation and description of a phenomenon
  • Formulation of an hypothesis to explain the phenomena
  • Use of the hypothesis to predict the existence of other phenomena, or to predict quantitatively the results of new observations
  • Performance of experimental tests by several independent experimenters and properly designed experiments
• Sources of Experimental Error

  • Random error
  • Non-random or systematic error
• Hypothesis


  A limited statement regarding cause and effect in specific situations; it also refers to our state of knowledge before experimental work has been performed and perhaps even before new phenomena have been predicted
• Models


  For situations when it is known that the hypothesis has at least limited validity
• Scientific theory or law


  Represents a hypothesis, or a group of related hypotheses, which has been confirmed through repeated experimental tests
• Variables in an Experiment

  • Independent variable
  • Dependent variable
  • Controlled variable
• Dehydration


  Creation of larger molecules
• Hydrolysis


  Breakdown of larger molecules
• Organic Macromolecules


  • Proteins
  • Carbohydrates
  • Lipids
• Proteins


  Monomers: Amino Acids (20)<|>Polypeptide chains<|>Broken down by proteinases<|>Found in enzymes, blood cells, receptors and muscle tissue<|>Created by RNA during DNA Transcription and Translation<|>Biuret Test (+) blue -> violet (clustering of amide ions)
• The protein consists of two polypeptide chains, a long one on the left of 346 amino acids — it is called the heavy chain — and a short one on the right of 99 amino acids
• Protein structure


  • Three extracellular domains, designated here as N (includes the N-terminal), C1, and C2
  • Transmembrane domain where the polypeptide chain passes through the plasma membrane of the cell
  • Cytoplasmic domain (with the C terminal) within the cytoplasm of the cell
  • Dark bars represent disulfide (S—S) bridges linking portions of each external domain (except the N domain)
• Carbohydrates


  Monomers: monosaccharide/simple sugar<|>Disaccharide (2 units)<|>Oligosaccharide (3-10 units)<|>Polysaccharide/complex sugar
• Carbohydrate tests


  • Benedict's Test (+): blue -> brown -> red
  • Starch Test (+): black-blue after addition of iodine
• Starch


  • Amylose: linear chains of several hundred glucose units linked by a 1-4 glycosidic bond
  • Amylopectin: highly branched several thousand glucose units. A short side chain is linked to C6 (the carbon above the ring)
  • Hydrolysis of starch is done by amylases
• Cellulose


  • Orientation of the glycosidic bonds: glucose rings arranged in a flip-flop manner -> long, straight, rigid molecule
  • No side chains in cellulose -> lie close together
  • Many -OH groups -> many hydrogen bonds to form
• Glycogen


  Animal storage form<|>Structure is similar to amylopectin, although the branches tend to be shorter and more frequent<|>Stored mostly in liver and muscles<|>Glycogen is broken back down into glucose when energy is needed via glycogenolysis
• Lipids


  Monomers: 3 F.A. chains + glycerol bound by ester linkage = triglyceride<|>Hydrophobic<|>Saturated - all single bonds; maximum possible amount of hydrogens, solid at room temperature<|>Mono/Polyunsaturated – one/multiple double/triple bond; not bonded to maximum hydrogens, liquid at room temperature<|>Cis – carbon chains on same side "good oils"<|>Trans – carbon chains on opposite side "trans fats = bad oils"
• Lipoproteins


  Clusters of proteins and lipids all tangled up together<|>Means of carrying lipids, including cholesterol, around in our blood<|>LDL or low density lipoprotein "bad guy," associated with deposition of cholesterol<|>HDL or high density lipoprotein "good guy," associated with carrying "cholesterol" out of the blood
• Phospholipids


  Glycerol + two fatty acids + phosphate group with some other molecule attached to its other end<|>Hydrocarbon tails of the fatty acids are still hydrophobic, but the phosphate group end of the molecule is hydrophilic because of the oxygens with all of their pairs of unshared electrons<|>Soluble in water and oil - "emulsifying agent"
• Steroids


  Consist of two six-membered and two five-membered rings