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Bio Cheating Thingy woo Cheat Sheet (DRAFT) by

Photosynthesis and Cellular Respiration

This is a draft cheat sheet. It is a work in progress and is not finished yet.

Catabolic Pathways

Cells break down glucose and other organic fuels in order to create ATP.
Fermen­tation is a process that results in the partial breakdown of glucose to ATP without the use of oxygen.
Aerobic respir­ation uses oxygen as a reactant while in anerobic processes it uses a different reactant such as sulfur.
The cell can tap into the energy stored in food particles through redox reactions, where electrons completely shift from one substancxe to another.
Oxidation is the loss of electrons from a substance while a reduction is the adding of electrons to another.
During aerobic respir­ation, glucose is oxidized to CO2 and O2 is reduced to H2O.
Electrons are usually passed first to NAD+ forming NADH, the electrons then move to the electron transport chain, which conducts them to O2 in energy releasing steps.
The three stages of Aerobic respir­ation are: Glycol­ysis, the Kreb Cycle, and Oxidative Phosph­ory­lation (ETC)

Photos­ynt­hesis converts light energy to food.

In eukaryotes that are autotrophs such as plants, photos­ynt­hesis occurs in chloro­plasts.
A chloro­plast is an organelle containing thylak­oids, stacks of thylakoids form grana.
Photos­ynt­hesis equation: 6CO2 + 12H2O + Light Energy ----> C6H12O6 + 6O2 + 6H2O
Light reactions in the thylakoid membrane split water, releasing O2.
The Calvin cycle in the stroma forms sugars from CO2.
 

Glycolisis

Glycolisis splits a glucose molecule into two pyruvate molecules through a series of reactions.
Pyruvate then goes on to be part of the citric acid cycle.
Glycolysis nets 2 ATP and 2 NADH per glucose molecule.

The Kreb Cycle

In eukaryotic cells, after glucose has been split into two pyruvate, the pyruvate is then oxidized to acetyl CoA.
The acetyl CoA then enters the Kreb Cycle and is further oxidized.

Glycolysis + Kreb connect to Metabolic Pathways

Catabolic pathways funnel electrons from many kinds of organic molecules to cellular respir­ation.
Amino acids of proteins must be deaminated before being oxidized.
Fatty acids undergo deta oxidiz­aation to two-carbon fragments and then enter the Kreb cycle as acetyl CoA.

Light reactions convert solar energy to chemical

Light is a form of electr­oma­gnetic energy, the colors we see as visible light include the wavele­ngths that drive photos­ynt­hesis.
Chloro­phyll a is the main pigment of photos­ynt­hesis in plants.
A pigment goes from a ground state to an excited state when a photon boosts one of the pigments electrons to a higher energy electron shell.
A photos­ystem is composed of a reaction center complex surrounded by light harvesting complexes.
Linear electron flow during the light reactions uses both photos­ystems and produces NADPH, ATP, and Oxygen.

Light reactions convert solar energy to chemical

Light is a form of electr­oma­gnetic energy, the colors we see as visible light include the wavele­ngths that drive photos­ynt­hesis.
Chloro­phyll a is the main pigment of photos­ynt­hesis in plants.
A pigment goes from a ground state to an excited state when a photon boosts one of the pigments electrons to a higher energy electron shell.
A photos­ystem is composed of a reaction center complex surrounded by light harvesting complexes.
Linear electron flow during the light reactions uses both photos­ystems and produces NADPH, ATP, and Oxygen.
 

The ETC and Chemio­smosis

NADH and FADH2 transfer electrons to the ETC.
Electrons move down the chain due to the charge of the Oxygen, these electrons eventually are passed to the O2 forming H2O.
Electron tranfer in the ETC causes protein complexes to H form the mitoch­ondrial matrix to the interm­embrane space.
H diffuses back into the membrane through ATP synthase, driving the phosph­ory­lation of ADP
About 34% of the energy in a glucose molecule is transf­erred to ATP during cellular respir­ation

Fermen­tation and Aerobic Respir­ation

Glycolysis nets 2 ATP by substrate level phosph­ory­lation, this can be done with or without oxygen
Under conditions without oxygen, either anerobic respir­ation or fermen­tation can take place.
In anerobic, an ETC is present with a final electron acceptor other than oxygen.
In fermen­tation, the electrons from NADH are passed to pyruvate or a derivative of pyruvate regene­rating the NAD+ required to oxidize more glucose.
Two common types of fermen­tation are alcohol fermen­tation and lactic acid fermen­tation.
Fermen­tation, anerobic respir­ation, and aerobic respir­ation all use glycolysis to oxidize glucose, but the differ in their final electron acceptor and whether an ETC is used.

Calvin Cycle

Calvin cycle occurs in the stroma, it uses electrons from NADPH and energy from ATP. One molecule of G3P exits the cycle per three CO2 molecules fixed.
C3 plants close their stomata on hot dry days to prevent loss of water.
Under hot condit­ions, photor­esp­iration can occur, where Rubisco binds O2 instead of CO2, consuming ATP but releasing CO2.
C4 plants are adapted to hot enviro­nments, they incorp­orate CO2 into four carbon compounds.
CAM plants are also adapted to hot climates, they only open their stomata at night.