Mrs. Ragsdale Bio SL

All living things have the same basic chemical elements: Carbon - C Oxygen - O Hydrogen - H Nitrogen - N

Sulphur - Necessary for amino acids Calcium – Building bones, teeth, heart health Iron – Found in hemoglobin (in animals) Sodium – Used in nerve impulses Phosphorus – Needed for cell membrane and structures

Polar Molecules – an unequal pulling in covalent bonds Creates positive and negative “poles” Nonpolar Molecules – equal pulling 100% neutral charge all the way around

Covalent bonds are between nonmetals Oxygen is bigger and stingier than Hydrogen The electron pair is closer to oxygen than hydrogen Creates a slightly negative oxygen dipole and a slightly positive hydrogen dipole

The small positive charge is highly attracted to the small negative charge One molecule becomes bonded to another molecule because of this slight attraction We call this Hydrogen Bonding

Hydrogen bonding does NOT change the chemical properties of the individual water molecules However!!! It explains why water has such unique and amazing physical properties

Cohesion – water’s ability for its molecules to “stick together” Allows for just enough structural strength to allow certain insects to glide Makes it possible for plants to transport water through their tissues (transpiration)

Solvent Properties – Water has the ability to dissolve countless substances because of its polarity. Water is the medium for almost all metabolic reactions Because so many things can be dissolved in water, it acts as a transport medium for almost all living organisms.

Thermal Properties Heat Capacity – it requires a large amount of energy to raise its temperature because the hydrogen bonds must be broken Boiling Point – 100⁰C (again really high because of the hydrogen bonds) Coolant – When water evaporates, it pulls heat from its surroundings to go from liquid to gas.

Oceans, lakes and ponds have fairly stable temperature (since it can absorb a lot of heat without a temperature change) which means that poikilothermic organisms need not waste energy on thermoregulation. Surrounding air temperatures may show marked changes but water in the same vicinity will remain relatively stable.

Mrs. Ragsdale Biology SL

Organic Compounds Inorganic Compounds Carbon based Found in all living things Exceptions: hydrogen carbonate (HCO3- ), carbon dioxide (CO2 )and carbon monoxide (CO) Inorganic Compounds By default, anything that is not organic

Macromolecules – macro “big” molecules Monomers – the building blocks Polymers – the completed structure Polymerization – when you have a large structure that is made up of small building blocks Proteins are made up of chains of amino acids

Monosaccharide Sugars Amino Acids Fatty Acids

Glucose: C6H12O6 (6 Carbon Sugar) Product of photosynthesis

Ribose – 5 carbon sugar Modified version of ribose is deoxyribose

Type of Saccharide Names: Monosaccharide Glucose, galactose, fructose Disaccharide Maltose, lactose, sucrose Polysaccharide Starch, glycogen, cellulose

Name (Animal – A, Plant – P) Type of Saccharide Function Glucose (A) Mono Respiratory substrate (cellular respiration) Fructose (P) Common sugar found in fruit Lactose (A) Di Common sugar found in milk Sucrose (P) Highly soluble, Metabolically inactive Glycogen (A) Poly Energy storage, polymer of glucose Cellulose (P) Insoluble structural fibers in plants

Monomers of Proteins Consist of nitrogen, carboxylic acid and an “R” group R group is what makes each of the 20 amino acids unique

Made up of saturated and unsaturated fatty acids Saturated – every possible place where a C molecule can bond is filled with a Hydrogen All single bonds Straight chains Unsaturated – there are places where C=C double bonds form Bent chains

More easily digested so quicker form of energy storage Carbohydrates Lipids 4cal / g 9cal / g More easily digested so quicker form of energy storage Lighter energy source for the same amount of energy Soluble in water so easy to store and transport Insoluble in water – do not cause problems with osmosis in water Require more oxygen / molecule metabolized Can only be used at lower levels of energy demand (In other words you tend to burn carbs and protein before fats)

Polymerization – putting together individual monomers to make polymers Condensation – Two molecules are joined together to form a larger molecule by removing water Two proteins ->dipeptide. Three proteins -> polypeptide. Monosaccharides -> Disaccharides -> Polysaccharides Two lipids -> glyceride. Three lipids -> triglyceride.

Lysis – to break Breaking down large molecules by adding water

http://www.youtube.com/watch?v=6lITtMESI8I &feature=related http://www.youtube.com/watch?v=UyDnnD3fM aU http://www.youtube.com/watch?v=b7TdWLNh MtM&NR=1