Oxygen is the final electron acceptor. It oxidises the final carrier in the ETC on the inner mitochondrial membrane and is reduced to water.
Hydrogen ions flow from the inter membrane space into the matrix via ATP synthase, this electrochemical gradient phosphorylates ADP.
Hydrogen ions are pumped from the matrix into the inter membrane space, using the energy from the electrons flowing along the ETC. The electrons come from the oxidation of food, transferred by coenzymes NAD and FAD.
Glycolysis occurs in the cytoplasm. Link and Krebs in the matrix. Link and Krebs produce carbon dioxide by the removal of a carboxyl group.
Fermentation is just glycolysis with a different way of regenerating NAD (from NADH) by the reduction of pyruvate (or ethanal).
Substrate level phosphorylation is the direct addition of phosphate to ADP, occurs in glycolysis (4 ATP) and Krebs (once per turn), chemiosmosis is H ions flowing through ATP synthase.
Cristae give a larger surface area for oxidative phosphorylation
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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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Cell membranes, osmosis, diffusion , active transport, - lots of experimental and application questions
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Protein Synthesis - exam questions a quiz and powerpoints, videos and animations, please like and share
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AS OCR Breadth in biology H020/01 June 2017 Multiple Choice Questions as an auto-marking online quiz
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Oegenesis, Gametogenesis, Fertilization in Humans
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Excellent immunity resources
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Plant transport guide - videos, powerpoints, questions
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OCR released the OCR A June 2017 H420 papers. I combined the Biological DIversity 420/02 paper with the markscheme to make it easier to follow and interpret.
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AQA released the June 2017 Biology papers - they are all available at
http://www.aqa.org.uk/subjects/science/as-and-a-level/biology-7401-7402/assessment-resources
I combined the 7402/01 paper with the markscheme to make it easier to follow and interpret. If you find it useful then please like and share.
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AQA released the June 2017 Biology papers - they are all available at
http://www.aqa.org.uk/subjects/science/as-and-a-level/biology-7401-7402/assessment-resources
I combined the 7402/02 paper with the markscheme to make it easier to follow and interpret. If you find it useful then please like and share.
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AQA released the June 2017 Biology papers
I combined the 7402/03 paper with the markscheme to make it easier to follow and interpret. If you find it useful then please like and share.
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OCR released the OCR A June 2017 H420 papers. I combined the Unified Biology 420/03 paper with the markscheme to make it easier to follow and interpret.
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OCR released the OCR A June 2017 H420 papers. I combined the Biological Processes 420/01 paper with the markscheme to make it easier to follow and interpret.
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Plant reproduction - videos questions and resources
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Tips on how to answer the AQA A-level Biology Extended Essay.
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Stunning video and images from Royal Microscopical Society
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Homeostasis - Glucose and Temperature - for AQA and OCR
Question Pack, Videos, Powerpoints
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Question pack, powerpoint and videos on the liver
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OCR A Level Biology A H420/01 Biological processes Sample Question Paper - as an online quiz
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