1. ATP
1.1. Immediate source of energy in a cell
1.2. Energy in ATP is stored in high energy bonds between the phosphate groups - released via hydrolysis reaction
1.3. When energy is needed by a cell, ATP is broken down into ADP and inorganic phosphate
1.3.1. Is a hydrolysis reaction; a phosphate bond is broken and energy is released - reaction catalysed by the enzyme ATP hydrolase
1.3.2. ATP can be re-synthesised in a condensation between ADP and Pi; happens during respiration and photosynthesis
2. The Importance of Water
2.1. Important in metabolic reactions
2.1.1. Condensation and Hydrolysis
2.2. Polar Molecule - partial negative on one side, partial positive on other side
2.3. Has a High Latent Heat of Vaporization
2.4. Takes alot of energy needed to break the hydrogen bonds between the water molecules
2.5. Can Buffer (Resist) changes in temperature
2.5.1. Hydrogen bonds absorb energy, so has a high specific heat capacity
2.5.2. Helps animals contain constant internal body temperature
2.6. Good Solvent
2.6.1. Water's polarity makes it a useful solvent
2.7. Strong Cohesion between Water molecules
2.7.1. Cohesion is the attraction between molecules of the same type - water is cohesion due to being polar
2.7.2. Strong cohesion helps water to flow, making it great for transporting substances
2.7.3. Has a high surface tension when it comes into contact with air
3. The Importance of Inorganic Ions
3.1. Ions have electric charge
3.1.1. Positive Charge is Cation
3.1.2. Negative Charge is Anion
3.2. Iron Ions
3.2.1. Part of Haemoglobin
3.2.2. Haemoglobin is a large protein that carries oxygen around the body, the red blood cells
3.2.3. Made up of four different polypeptide chains
3.2.4. Fe2+ binds to oxygen in Haemoglobin
3.3. Hydrogen Ions
3.3.1. Determine pH
3.3.2. Calculated based on the concentration of hydrogen ions
3.4. Sodium Ions
3.4.1. Helps transport Glucose and Amino Acids across membranes
3.4.2. Known as co-transport
3.5. Phosphate Ions
3.5.1. Are essential component of ATP and DNA
3.5.2. DNA, RNA and ATP all contain phosphate groups
3.5.3. Phosphate group is attached to phosphate ion
3.5.4. Bonds between phosphate groups that store energy in ATP
4. DNA
4.1. Two strands of polynucleotide chain
4.1.1. Double Helix
4.2. Made up of organic bases - adenine, guanine, cytosine and thyamine
4.3. Hydrogen bonds between bases
4.4. Carries hereditary information in many organisms
4.5. Necessary for production of protein
4.6. Pentose sugar in DNA nucleotide is called an deoxyribose
5. RNA
5.1. Contains nucleotides with a ribose sugar
5.2. Made up of organic bases - adenine, guanine, cytosine and uracil
5.3. Transfers genetic information from the DNA to the ribosomes
5.3.1. Ribosomes read the RNA to make polypeptides in a process called translation