A2 AQA Biology Topic 5 Already Passed

A2 AQA Biology Topic 5 Already Passed Glucose C6H12O6 - a single sugar which is produced in photosynthesis. ATP An activated nucleotide found in all living organisms, which is produced during respiration and acts as an energy carrier. ATP is produced during the light-dependent reaction of photosynthesis. metabolism the chemical processes that occur within a living organism in order to maintain life. Photosynthesis A complex metabolic pathway involving many intermediate reactions. Some energy in light is conserved in the form of chemical bonds. There are three main stages: capturing the light energy, the light-dependent reaction and light-independent reaction. Photolysis Light energy splits 2 water molecules into 4 electrons, 4 hydrogen ions (protons) and an oxygen molecule (light-dependent reaction). These electrons replace the electrons lost from a chlorophyll molecule when light strikes it. Oxidation Loss of electrons or loss of hydrogen or gain of oxygen with a substance Reduction Gain of electrons or gain of hydrogen or loss of oxygen from a substance Co-enzyme A non-protein compound that is necessary for the functioning of an enzyme. (NOT AN ENZYME!) Play a huge role in photosynthesis and respiration where they carry hydrogen atoms from one molecule to another. E.g. NAD, FAD and NADP. NADP An electron carrier that is important in photosynthesis. When it takes up protons the NADP becomes reduced. NADPH Reduced NADP - it is the main produced of the light-dependent stage and it enters the light-independent reaction taking with it the electrons from the chlorophyll molecules. Chloroplast The cellular organelles where photosynthesis takes place. Typically 2-10μm long and 1μm in diameter and are surrounded by a double membrane which inside it contains two distinct regions: the grana and stroma. Thylakoid Disc like structures which make up the grana in stacks of up to 100. Where the light-dependent stage of photosynthesis takes place. They contain the photosynthesis pigment chlorophyll. Some may have tubular extensions (intergranal lamellae) which join up with thylakoids in adjacent grana. Stroma Fluid-filled matrix where the light-independent stage of photosynthesis takes place. Chlorophyll Photosynthetic pigment inside thylakoids which absorbs light energy. Can become ionisied. Light-dependent reaction Stage of photosynthesis in which light energy is required to produce ATP and reduced NADP Photoionisation Process by which a chlorophyll molecule becomes ionised. Caused by the chlorophyll molecule absorbing light energy and boosting the energy of a pair of electrons within a chlorophyll molecule, raising them to a higher energy level and they become so energetic they leave the chlorophyll molecule altogether and are taken up