Photosynthesis Tips - Notes, videos, powerpoints and a pack of long questions and then a (difficult) Quiz to test your understanding

Powerpoints and notes, a pack of long data analysis exam questions and a test on photosynthesis

Tips for Photosynthesis

LDR - occurs on the thylakoid membranes. Limiting factor is light intensity

  • Phosphorylates ADP (through chemiosmosis) - creates the Hydrogen ion gradient by the flow of electrons along the ETC in the thylakoid membrane. The flow of electrons is driven by the capturing of light by a range of different pigments which channel the energy to a chl a molecule at the reaction centre of the photosystem - which then loses an electron.

  • Reduces NADP with an electron from splitting water (photolysis) at PSII.

Light Independent Reaction (reduction of carbon dioxide) - occurs in the stroma (the cytoplasm of the chloroplast).

  • Limited by speed and quantity of RUBISCO enzyme (kinetic energy - temperature) and substrate concentration (Carbon dioxide)

  • Needs the products of the LDR - ATP and NADPH

  • NADPH and ATP are used to regenerate RUBP

  • Each time the Calvin cycle turns, a single Carbon is reduced. 3 turns - one extra Triose Phosphate. 6 turns - 2 extra TP = 1 extra glucose.

  • TP is the source of all of the carbon in all plants (and hence in all heterotrophes) - Amino acids, DNA, RNA, phospholipids etc

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