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What is the most frequently occuring chemical elements in living things?
- Carbon
- Hydrogen
- Oxygen
- Nitrogen
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What variety of other elements are needed by living organisms?
- sulfur
- calcium
- phosphorus
- iron
- sodium
- PICSS
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Role of calcium?
- humans: needed to strengthen bone/teeth
- influences membrane permeability
- activator for several enzymes
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role sulphur?
needed for synthesis of 2/20 amino acids
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role of phosphorus
part of phosphate groups in DNA, RNA, ATP and coenzyme molecules, (cell membrane) phospholipids too
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role o iron
animal cells: iron needed structure of heme groups in hemoglobin
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role o sodium
- influences ionic balance cells for osmosis
- pumped in to cytoplasm to raise solute concentration and cause water to enter
- animal: sodium used by neurons to transmit nerve impulses
- plants: helps maintain turgor pressure
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Draw and label diagram showing structure water molecule to show ppolarity and hydrogen bond formation and covalent bonds
- draw second diagram w/ hydrogen bonds

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What 3 properties of water make it significant to living organisms?
- cohesion, solvent properties, thermal properties
- result of hydrogen bonds
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Outline the thermal (3), cohesive, and solvent properties of water
- cohesion: water molecules stick due to hydrogen bonding
- solvent properties: universal solvent, polar nature allows many substances to dissolve in water "like dissolves like" (ions, polar molecules like glucose)
- thermal prop; heat capacity: has large heat capacity, lots of energy needed to raise water temperature, stored heat energy given out when water cooled
- thermal prop; boiling/freezing point: relatively high boiling point, hydrogen bonds must be broken to change state from liquid to gas; high freezing point, density decreases as it freezes, ice forms at surface first
- therm prop; cooling effect o evaporation: can evaporate at temp below boiling, hydrogen bonds must be broken, heat enrgy taken fr liquid water = cool down
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What are the three uses for water in terms of living organisms?
- coolant
- medium for metabolic reactions
- transport medium
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Explain water's significance to living organisms as a transport medium
- transport medium: cohesion, solvent properties, heat capacity
- xylem of plants to allow transport columns of water to tops of trees, cohesion and hydrogen bonds
- solvent=universal solvent b/c polarity dissolving inorganic particles w/ charges, organic substances w/ polar molecules and enzymes
- allows substances to be dissolved in blood o animals and sap of plants to provide transportation throughout organism
- large heat capacity allows water to transport heat fr warmer parts of body to cooler
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Explain water's significance to living organisms as a coolant
- evaporation water from leaves (transpiration) and from human sweat =cooling effect
- water can evaporate at temp below boiling
- as bonds break, require energy and takes heat fr liquid water cooling down person
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Explain water's significance to living organisms as a medium for metabolic reactions
- solvent property, specific heat capacity
- most chemical reactions take place between all of the subtances dissolved in water
- high boiling point/freezing allows it to stay above freezing and below boiling in most places on eath = liquid acts as medium for metabolic reactions
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Distinguish between organic and inorganic compounds
- Organic compound – compounds found in living organisms and contain carbon
- (except hydrogen carbonates, carbonates, oxides carbon in humans but inorganic CO3 COx HCO3)
- Inorganic compound – compounds that do not contain carbon
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glucose
- hydroxyl groups from left to right
- down, up, down, down
- hexagon, 6 carbons
- C6H12O6

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ribose
- pentagon
- two hydroxyls down at bottom
- C6H12O6

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amino acids
 - amine group on one end, carboxyl on other
- each 20 amino acids has a different r group
- butterfly
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fatty acids
 - carboxy group one end
- C and three H on other end
- fishbone
- forms limited bonds b/c only one functional group
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List three examples of each monosaccharides, disaccharides, and polysaccharides
- Monosaccharides: glucose, galactose,fructose
- Disaccharides: maltose, lactose, sucrose
- Polysaccharides: starch, glycogen, cellulose
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State a function of glucose, lactose, and glycogen in animals and fructose, sucrose and cellulose in plants
- animals
- Glucose: used as energy source for thebody
- Lactose: sugar in milk, provides energy to new born until they are weaned
- Glycogen: used as short term energy source stored in muscle and liver
- plants
- Fructose: makes fruits sweet, attracts animals to eat fruit and disperse seeds
- Sucrose: used as energy source for the plant
- Cellulose: cellulose fibres makes plant wall strong
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Outline the role of condensation and hydrolysis in the relationships between monosaccharides, disaccharides and polysaccharides
- monosaccharides undergo condensation (remove water) to become disaccharides/polysaccharides
- glucose + glucose -> maltose + water

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between amino acids and polypeptides
- condensation joins 2 amino acids to form a dipeptide
- polypeptide formed when more amino acids added
- amino acid + amino acid -> dipeptide + water
- multiple amino acids -> polypeptide + many water molecules

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between fatty acids, glycerol and triglycerides
- 3 fatty acids joined to glycerol by ester bonds
- three water molec produced
- no chain formed
- diglycerid: 2 fatty acid + glycerol
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Condensation
- A reaction in which two molecules combine to form a larger molecule through removal of water
- one molecule of water produced for each time another subunit is attached
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hydrolysis
- The chemical breakdown of a compound due to addition of water.
- reverse of condensation
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state three functions of lipids
- Energy storage in the form of fat in humans, and oil in plants
- Used as heat insulation as fat under skin, reducing heat loss
- Allow buoyancy (b/c less dense than water) so animals can float in water
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Compare use of carbohydrates and lipids in energy storage
- both can be used as energy storage in living organisms
- carb for short term storage, lipids for long term
- lipids contain more energy/g than carbs
- stores of lipids = lighter than stores o carbs tt contain same amnt energy
- carbs more easily digested; energy stored released more rapidly
- due to water solubility, carbs easier to transfer from store
- carbs polar soluble in water, lipids nonpolar not
- lipids dont cause problems osmosis in cells due to water solubility
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primary structure
- number and sequence amino acids in polypeptide
- most polypeptides are 50-1000 amino acids long
- primary structure determined by nuceotide sequence in a gene in DNA
- -N-C-C-N-C-C-N-C-C- backbone
- has r group
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significance of primary structure
- correct sequence of amino acids decides the final conformation and function of the protein
- changing one could alter final conformation = useless
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secondary structure
- Regular repeating structure
- α-helices (myosin) and β-pleated sheets (silk protein)
- stabilized by hydrogen bonds tt form b/twn nearby amino acids in main chain of polypeptide
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significance secondary structure
- Proteins that contain secondary structures will have regions that are cylindrical (α-helices) and/or regions that are planar (β-pleated sheets).
- coiling and folding o polypeptide chain can form fibrous proteins and contribute to globular protein structure
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tertiary structure
- three-dimensional conformation o polypeptide
- Occurs as a result of the protein folding
- stabilized by side chain (R-group)
- interactions include ionic bonds, hydrogen bonds, hydrophobic interactions, disulfide bridges, strong covalent bonds
- strongest
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significance tertiary structure
- final shape of polypeptide
- may make it a functional protein
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quaternary structure
- linking 2 or more polypeptides to form single protein
- In some cases, some proteins can have a non-polypeptide structure called a prosthetic group.
- These proteins are called conjugated proteins.
- haem group in haemoglobin is a prosthetic group.
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significance quaternary structure
makes functional proteins
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Examples of quaternary structures
- insulin
- collagen
- hemoglobin: 4 polypeptides + heme group (conjugated protein)
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Outline the difference between fibrous and globular proteins w/ reference to two examples o each protein type
- fibrous and globular = both quaternary structure
- fibrous: long and narrow in shape; mostly insoluble e.g. collagen, myosin
- globular: rounded shape, mostly soluble e.g. hemoglobin, insulin
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