Zusammenfassung der Ressource
ATP and Respiration
- Anaerobic
- Animals and Prokaryotes
- In the cytoplasm, one glucose is phosphorylated
into glucose diphosphate using 2 ATP
- The glucose diphosphate splits into
two molecules of triose phosphate
- The two triose phosphate molecules are dehydrogenated by
dehydrogenase, oxidising them into two pyruvate
- Also, two NAD+ are reduced into NADH and four
ATP are formed by substrate-level phosphorylation
- The two pyruvate accept the hydrogen from the
NADH, converting it into NAD+, this froms two lactate
- Plants and Fungi
- In the cytoplasm, one glucose is phosphorylated
into glucose diphosphate using 2 ATP
- The glucose diphosphate splits into
two molecules of triose phosphate
- The two triose phosphate molecules are dehydrogenated
by dehydrogenase, oxidising them into two pyruvate
- Also, two NAD+ are reduced into NADH and four
ATP are formed by substrate-level phosphorylation
- The two pyruvate is decarboxylated, releasing
carbon dioxide, forming two ethanal
- The two ethanal accept the hydrogen from the NADH,
converting it into NAD+, this froms two ethanol
- Aerobic Respiration
- Glycolysis
- In the cytoplasm, one glucose is phosphorylated
into glucose diphosphate using 2 ATP
- The glucose diphosphate splits into
two molecules of triose phosphate
- The two triose phosphate molecules are dehydrogenated
by dehydrogenase, oxidising them into two pyruvate
- Also, two NAD+ are reduced into NADH and four
ATP are formed by substrate-level phosphorylation
- Link Reaction
- Pyruvate diffuses from the cytoplasm
into the mitochondrial matrix
- The pyruvate is dehydrogenated with dehydrogenase
and the hydrogen is accepted by NAD+ to from NADH
- The pyruvate is decarboxylated at the same
time by decarboxylase to form carbon dioxide
- When the pyruvate is dehydrogenated
and decarboxylated it forms acetate
- The acetate combine with coenzyme
A to form acetyl coenzyme A
- Kreb's Cycle
- Acetyl coenzyme A enter the Kreb's cycle by combing with a 4-carbon
acid, forming a 6-carbon acid and the coenzyme A is regenerated
- The 6-carbon acid is dehydrogenated, making NADH and is
decarboxylated to make carbon dioxide, forming a 5-carbon acid
- The 5-carbon acid is dehydrogenated, making NADH and FADH and is
decarboxylated to make carbon dioxide and to regenerate the 4-carbon acid
- The 4-carbon acid can combine with more acetyl coenzyme A and repeat the cycle
- Each cycle of the Kreb's cycle produces one ATP by substrate-level phosphorylation,
three molecules of NADH, one molecule of FADH and two molecules of carbon dioxide
- Adenosine Triphosphate
- What is ATP
- ATP is the universal energy currency, meaning
it is used in all cells to drive their reactions
- ATP is made up of three phosphate molecules, one
adenine molecule and one ribose molecule
- ATP is inert, can pass out of mitochondria into the cytoplasm, releases energy efficiently, releases
energy in useable quantities, is easily hydrolysed and is readily reformed by phosphorylation
- Proton Gradients
- Photosynthesis
- Electrons are excited by energy from light, these electrons
move through a series of carriers in the thylakoid membranes
- Their energy pumps protons from the stroma into
the spaces between the thylakoid membranes
- The energy is released in chemiosmosis, in which protons flow back down
an electrochemical gradient into the stroma, through ATP synthetase
- The energy is incorporated into ATP, this ATP drives the light-dependent reactions of
photosynthesis and energy is incorporated into the macromolecules made by the cell
- Respiration
- Electrons are excited by energy derived from food molecules, their energy is made
available as they move through a series of carriers on the inner mitochondrial membrane
- The energy pumps protons across the membrane, from the
matrix into the inter-membrane space, setting up a proton gadient
- Energy is released in chemiosmosis, as the protons flow back into
the matrix through ATP synthetase, and is incorporated into ATP
- The Electron Transport Chain
- Respiration
- Hydrogen atoms derived from the respiratory breakdown of glucose are transferred by dehydrogenase
enzymes to coenzymes NAD and FAD and carried to the inner membrane of the mitochondrian
- The electrons and protons of the hydrogen atoms have different pathways
but because they both move through the electron transport chain.
- For every two protons delivered by NADH, enough
energy is released to synthesise three molecules of ATP
- When FADH delivers two protons, enough
energy is released for only two molecules of ATP
- Photosynthesis
- Groups of pigments and proteins, called photosystems, transfer excited electrons to electron
acceptors and, from there, to a series of proton carriers, all on the thylakoid membranes
- Protons from the water and the electrons are transferred to the coenzymes NADP and
subsequently, to glycerate phosphate, in the pathway that synthesises carbohydrates
- The energy that powers the proton pump and electron transport chain in the
chloroplast comes from light, so chloroplasts synthesise ATP by photophosphorylation