Download energy, chemical reactions and organic compounds list the four

ENERGY, CHEMICAL REACTIONS AND ORGANIC COMPOUNDS LIST THE FOUR PRIMARY CATEGORIES OF ORGANIC COMPOUNDS 1.
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Carbohydrates Lipids Proteins Nucleotides and Nucleic Acids DISCUSS WHY CARBON IS USEFUL FOR FORMING BIOLOGICAL MOLECULES 
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It has four valence electrons, so it bonds with other atoms which need four to complete its shell. They readily bond with each other and can form long chained carbon backbones. Carbon commonly forms covalent bonds with hydrogen, oxygen, nitrogen and sulphur. Carbon backbones carry a variety of functional groups (clusters of atoms that determine many of the properties of an organic molecule) examples include carboxyl, hydroxyl, methyl, amino and phosphate groups. DESCRIBE THE STRUCTURE OF THE MAIN TYPES OF MONOSACCHARIDES, DISACCHARIDES AND POLYSACCHARIDES Carbohydrates are hydrophilic (dissolve in water) organic molecules with a general formula of (CH2O)n, where n=number of carbon atoms. Glucose, which has 6 carbon atoms, has a formula of C6H12O6. Carbohydrates generally have a root (begins with) sacchar‐ or a suffix (ends with) ‐ose. Monosaccharides are simple sugars with a general formula of C6H12O6. Examples include glucose (blood sugar), galactose and fructose. They are produced by the digestion of complex carbohydrates. Disaccarides are sugar molecules composed of two monosaccharides. Examples include sucrose (glucose+fructose), lactose (glucose+galactose) and maltose (glucose+glucose). Polysaccharides are long chains of glucose. 
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Glycogen is the energy storage polysaccharide in animals; it is made in the cells of the liver, muscles, brain, uterus and vagina. o The liver produces glycogen after a meal then breaks it down to maintain a steady blood glucose level. o Muscles store glycogen for its energy requirements. o Uterus uses glycogen to nourish embryos. Starch is the energy storage polysaccharide in plants. Cellulose is the structural molecule of plant call walls; it is indigestible but needed as it is dietary fibre. 7 LIST FOUR FUNCTIONS OF CARBOHYDRATES 
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Carbohydrates are a source of energy that can be quickly mobilised. They are converted to glucose and oxidised to make ATP. Glucose forms blood sugar, an energy source for cells. Provide energy storage in the muscles and liver in the form of glycogen. Provides dietary fibre (cellulose) They are often conjugated (covalently bound) to proteins and lipids. o Glycolipids form part of the external surface of the cell membrane. o Glycoproteins form part of the external surface of the cell membrane and mucus of respiratory and digestive tracts. o Proteoglycans are gels that hold cells and tissues together, provide joint lubrication and give cartilage a rubbery texture. LIST AND DEFINE THE 5 DIFFERENT TYPES OF LIPIDS Lipids are hydrophobic (not dissolvable in water) organic molecules which are composed of carbon, hydrogen and oxygen. Lipids are less oxidised than carbohydrates, therefore have more calories/gram. 1.
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Fatty Acids – a chain of 4 – 24 carbon atoms with a carboxyl group on one end and a methyl group on the other and hydrogen bonded along the sides. Can be saturated (as much hydrogen as it can carry) or unsaturated (have carbon atoms joined by double bonded covalent bonds with no hydrogen). Triglycerides – are made up of three fatty acids covalently bonded to a glycerol molecule by dehydration synthesis. If a triglyceride is liquid at room temperature it is an oil (polyunsaturated from plants, if it is solid it is a fat (saturated fat from animals). Its primary function is energy storage, but also acts as thermal insulation and shock absorbing cushion for organs. Phospholipids – are essentially a triglyceride with one fatty acid replaced by a phosphate group. They are amphiphilic, the fatty acid tail is hydrophobic and the phosphate head is hydrophilic. Eicosanoids – are derived from a fatty acid called arachidonic acid. They primarily function as hormone‐like chemical signals between cells. Prostaglandin is a cell which is produced in all tissues and plays a role in inflammation, blood clotting, hormone action, labour contractions and the diameter of blood vessels. Steroids – a lipid with its carbon atoms arranged in four rings. Cholesterol is the parent steroid from which other steroids are synthesised (cortisol, progesterone, estrogens, testosterone and bile acids. Cholesterol is an important component of cell membranes and is naturally produced in our body (in the liver of all animals). 8 DISTINGUISH BETWEEN THE DIFFERENT FUNCTIONS OF THESE LIPIDS 
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Fatty acids ‐ building of triglycerides and source of energy. Triglycerides ‐ energy storage, thermal insulation, binding and cushioning organs. Phospholipids ‐ major component of cell membranes. Eicosanoids ‐ chemical messengers between cells, role in inflammation and blood clotting. Steroids ‐ helps to form steroid hormones such as cortisol, progesterone, estrogen and testosterone. DISTINGUISH BETWEEN AMINO ACIDS & THE DIFFERENT TYPES OF PEPTIDES A protein is a polymer of amino acids; the combination determines is structure and function. An amino acid is a carbon with three attachments, an amino, a carboxyl and a side chain known as an R‐Group. There are 20 unique amino acids, their R Groups all differ this determines the properties of the amino acid. Polar amino acids means it is charged and has a positive and negative end, nonpolar has no charge, effects shapes and structure. A peptide is two or more amino acids. 
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Dipeptides – have 2 amino acids Tripeptides – have 3 amino acids Oligopeptides – have fewer than 10‐15 amino acids Polypeptides – have more than 15 amino acids Proteins – have more than 100 amino acids LIST & DESCRIBE THE 4 LEVELS OF STRUCTURAL ORGANISATION IN PROTEINS 1.
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Primary structure – ring of amino acids in a sequence Secondary structure – how it is packaged, coiled (alpha helix) or folded (beta sheet). Joined together with hydrogen bonds. Tertiary structure – more folding and bending due to interactions of R‐groups to create a 3D structure. Quaternary structure – more than one subunit or polypeptide joined together. LIST AT LEAST 5 FUNCTIONS OF PROTEINS 1.
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Structure ‐ collagen, keratin Communication ‐ some hormones, cell receptors Membrane Transport ‐ proteins make up channels, carriers to carry chemicals across the membrane Catalysis ‐ enzymes allow chemical reactions to happen Recognition and protection ‐ antigens, antibodies and clotting proteins Movement ‐ muscles contract because proteins slide across each other Cell adhesion ‐ proteins bind cells together 9 DEFINE ENZYMES & OUTLINE THE 3 STEPS OF AN ENZYMATIC REACTION INVOLVING THE BREAKDOWN OF SUCROSE Enzymes are specific proteins that function as biological catalysts (they allow reactions to occur rapidly at normal body temperature) The substrate is the substance the enzyme acts upon. Enzymes are named by adding –ase to the substrate, ie the enzyme amylase digests starch (the substrate) otherwise known as amylose Enzymes assist molecular interaction by lowering activation energy (the energy needed to start a reaction) Steps in breakdown of sucrose 1.
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Substrate approaches active site on enzyme molecule Substrate binds to active site forming an enzyme‐substrate complex (highly specific, only one substrate works with the one enzyme, this is known as enzyme‐substrate specificity) Enzyme breaks covalent bonds between monomers in substrate by hydrolysis (adding water) and two products are released, glucose and fructose. Enzyme remains unchanged and can be used over and over again DEFINE AND GIVE EXAMPLES OF NUCLEOTIDES AND NUCLEIC ACIDS Nucleotides have 3 principal components 1.
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a single/ double carbon‐nitrogen ring (nitrogenous base) a sugar (monosaccharide) one or more phosphate groups Examples include adenosine triphosphate (ATP), cyclic adenosine monophosphate (cAMP) and adenosine diphosphate (ADP) Nucleic acids are polymers (long chains of nucleotides joined together) of nucleotides 
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Deoxyribonucleic acid (DNA) ‐ largest nucleic acid consisting of billions of nucleotides and which carries our genetic code Ribonucleic acid (RNA) ‐ smaller nucleic acid (70‐10,000 nucleotides long) which assists in protein synthesis 10