Biochem: Protein and Amino Acids Essay examples

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Biochemistry
Chemical elements and water
ESSENTIAL ELEMENTS: State that the most frequently occurring chemical elements in living things are carbon, hydrogen, oxygen and nitrogen (HONC)
State that a variety of other elements are needed by living organisms, including sulfur, calcium, phosphorus, iron and sodium. * Sulfur: * found in some amino acids * some bacteria use it to make food * calcium: * bone strength * helps enzymes work * phosphorus: * helps supply and release energy from ATP * also part of DNA * iron: * needed for production of hemoglobin * sodium: * important in cell membrane * sending never impulses
Outline the thermal, cohesive and solvent properties of water: * thermal properties: * Heat of vaporization * The amount of energy needed to turn a liquid into a gas * solvent properties: * What is the difference between solvent and solute? * Water is a good solvent because it is a polar molecule * It will dissolve polar solutes easily * Polar attractions cause water molecules to surround and isolate the solute molecules * All these hydrogen bonds between water molecules need to break for the liquid to change to gas * Water becomes less dense as it gets closer to the freezing point and so ice always forms on the surface first * The solvent properties of water mean that many different substances can dissolve in it because of its polarity
Carbs, lipids and proteins
Identify amino acids, glucose, ribose, and fatty acids from diagrams showing their structures: * Ribose:

List three examples each of monosaccharaides, disaccharides and polysaccharides:
Also, state one function of glucose, lactose, and glycogen in animals, and of fructose, sucrose and cellulose in plants: * Monosaccharaides: * Glucose: can be used to generate ATP * Fructose: sugar in fruit * Galactose * Ribose * Disaccharides: * Maltose: glucose and glucose * Sucrose: glucose and fructose = table sugar * Lactose: glucose and galactose = sugar in milk * Polysaccharides: * Cellulose: structural support for cell walls * Starch: storage of carbs for plants (usually in bulbs) * Glycogen: temporary storage for excess glucose for animals (usually in liver)
Outline the role of condensation and hydrolysis in the relationships between monosaccharaides, disaccharides and polysaccharides; between fatty acids, glycerol and triglycerides; between amino acids and polypeptides. * Polymer: consisting of large molecules made up of a linked series of repeated simple molecules called monomers * Monomers: simple molecular units * Condensation: * makes bonds * builds molecules

* with two amino acids water is removed * peptide bond is formed

* two glucose

* glycocidic bond ^^ * Hydrolysis: * Water is split to break bonds apart * Reverse of condensation
State the three function of lipids: 1. Lipids can be used for energy storage in the form of fat in humans and oil in plants. 2. Lipids can be used as heat insulation as fat under the skin reduces heat loss. 3. Lipids allow buoyancy as they are less dense than water and so animals can float in water.
Compare the use of carbs, and lipids in energy storage Carbs | Lipids | Short term storage | Long term storage | Soluble in water | Not soluble | Easy to transport around the body | Not so easy | Easier and more rapidly digested | 9 | 4 | |

Proteins * What is a protein? * Polymers of amino acids * Each has an unique 3-D shape * They vary in their structure of amino acids * Serve many purposes biologically
Explain the four levels of protein structure, indicating the significance of each level: 1. Primary: * Amino acid sequence: determined by the base sequence of the gene which codes for the protein, DNA * Sequence of amino acids are held