Ch.5 Flashcards
Metabolism
the sum of all chemical reactions within a living organism
Catabolism
the breakdown of complex molecules into smaller ones. Energy from catabolic reactions take that ADP, phosphate group, and energy and turn it into ATP
Anabolism
the building of more complex molecules from smaller ones. Anabolic reactions transfer energy from ATP to molecules (some heat/energy is lost) and it turns to ADP , a phosphate group, and energy.
Metabolic Pathway
a cell’s sequence of chemical reactions that is determined by it enzymes, which in turn is determined by what kind of cell it is.
Collision Theory
the idea that all atoms are colliding with each other at any given moment, and the energy transferred by particles in the collusion can disrupt the electron structures and cause chemical reactions
Reaction rate
the frequency of collisions between particles that have enough energy for a chemical reaction. You can increase this by heating water, as it causes the particles to move faster and thus more likely to collide
Reaction rate
the frequency of collisions between particles that have enough energy for a chemical reaction. You can increase this by heating water, as it causes the particles to move faster and thus more likely to collide
enzymes
biological catalyst made of amino acids (proteins))
substrate
the specific substance an enzymes reacts with
activation energy
the energy needed to cause a reaction. Enzymes lower their reaction energy with a substrate
ribozyme
RNA based enzyme, they can cut and splice RNA
enzyme-substrate complex
substrate contacts the active site of an enzyme
Enzyme Process
Substrate contacts the active site → an enzyme-substrate complex forms. → substrate is transformed by the rearrangement of existing atoms → the substrate is broken down and no longer fits in the active site
Multiple enzymes can impact a certain substrate, but will yield different results
apoenzyme, cofactor/coenzyme, holoenzyme
Enzymes need an apoenzyme (protein part) and a cofactor (non protein part). The cofactor can be a metal ion or if organic, is called a coenzyme. An apoenzyme is inactive by itself, and requires a cofactor, together they make a holoenzyme , or a complete whole enzyme
How do a cofactor/coenzyme help?
A cofactor can help by forming a bridge between an enzyme and substrate
A coenzyme can help by accepting atoms from the substrate or giving them to the substrate or the same with electrons
what are (NAD+), (NADP+)
two really important coenzymes made from vitamin B derivatives. either give/take atoms or electron
Which is oxidized, what type of reactions are they used for? NAD+, NADH,
NAD+ (Oxidized) , NADH (reduced) is normally used in catabolic reactions
Which is oxidized, what type of reactions are they used for? NADP+ , NADPH.
NADP+ (Oxidized), NADPH (reduced) is normally used in anabolic reactions
Which is oxidized? FAD, FADHv2
(FAD) , FADHv2 (reduced). These are more important enzymes
Coenzyme A (CoA)
contains a derivative of pantothenic acid, another B vitamin. It is important because it breaks down and synthesizes fats as well as in a series of oxidation reactions called the krebs cycle
turnover number
the maximum number of substrate molecules an enzyme molecule converts to product each second. Can be 1 to 10,000 molecules a second.
Factors that influence enzymes
Temp-, reg 98.6F, 100F is beneficial, at 105F your at the hospital, at 108F you denature proteins by breaking their bonds. pH- can also denature proteins 7.2-7.4 is our body ph
. Substrate concentration- higher concentration more activity, UP to the max limit because you have a limit amount of enzymes and inhibitors
What are inhibitors
competitive inhibitors take up the active site of an enzyme.non-competitive inhibitor will not bind to the active site but the allosteric site. This influences the shape of the enzyme and active site, and no longer can accommodate the substrate
Feedback Inhibition
where enzymes work together to further take down substrates, and because their shapes keep changing and thus accommodate different substrates
Intermediate A is the product after 1 round with an enzyme, followed by intermediate B etc. until end product
That end product then bounds onto the allosteric site, thus changing the shape, and substrate can no longer fit =, causing a pathway shutdown. This is good because you don’t want to make too much of something.
Oxidation-Reduction reactions
refers to the movement of electrons
Oxidation - removal of electrons from an atom or molecule (positive charge), Reduction - gain of electrons from an atom or molecule (negative charge)
Redox reaction
a mixture of an oxidation and reduction paired
How is ATP generated?
the phosphorylation of ADP
So ADP+ Phosphate group + energy = ATP
What are the 3 methods of phosphorylation
Substrate Level Phosphorylation, Oxidative Phosphorylation , Photophosphorylation
Substrate Level Phosphorylation
Energy from the transfer of a high-energy POv4- to ADP generates ATP (you see this in glycolysis )
Oxidative Phosphorylation
Energy released from transfer of electrons from one compound (Oxidation) to another (Reduction) in the electron transport chain is used to generate ATP and Chemiosmosis (two part process)
Photophosphorylation
Light causes chlorophyll to give up electrons
Energy released from transfer of electrons (oxidation) to make ATP via chemiosmosis
Carbohydrate catabolism
the breakdown of carbs to release energy
Carbohydrate catabolism (Process)
Glycolysis- start of oxidation of glucose
Intermediate step- oxidation of pyruvic acid
Krebs cycle- oxidation of acetyl Co A (basically)
Electron transport chain- oxidation of NADH and FADHv2
Combine this with chemiosmosis to make ATP
Glycolysis aka Embden-Meyerhof pathway process
oxidation of glucose into pyruvic acid and reduced NAD+ into NADH, produces ATP. The first part needs ATP at two different points , then the glucose (6 carbon) is split into two 3 carbon compounds glyceraldehyde-3-phosphate (GP) then dihydroxyacetone phosphate molecules (DHAP) . The second part gets 2 GP molecules and oxidizes them into pyruvic acid, getting 4 ATP and 2 NADH . Uses substrate level phosphorylation
Intermediate step process
2nd step, 2 pyruvic acid is oxidized and decarboxylated made into 2 acetyl CoA (because the acid still has some juice in it), the first reactant in the krebs cycle , Co2 is lost as a byproduct . In eukaryotes it happens in the mitochondria
Krebs Cycle or TCA cycle
3rd step, - produces 2 ATP by substrate level phosphorylation, reduces NAD+ and FAD into NADH and FADHv2, gives off co2 . Carriers from glycolysis and the krebs cycle donate electrons to ETC. You get 2 acetyl Co A from a glucose molecule, and thus you get 2 turns in the kreb cycle
You get 6 NADH per glucose and 2 FADHv2 and 2 ATP
Electron transport chain
4th step, carrier molecules are oxidized and reduced as electrons are passed down the chain,Oxygen is the final electron acceptor, that energy can then be turned into ATP with chemiosmosis
chemiosmosis
5th and final step, electrons from NADH or chlorophyll go into an electron transport chain , The high H+ concentration goes into a low H+ concentration ATP synthase protein through a proton gradient across the membrane, making the protein attach a phosphate onto ADP, making ATP
What are the prokaryotic alternative to, glycolysis
Pentose phosphate pathway and Entner doudoroff pathway , they happen in the cytoplasm and the last parts in the plasma membrane
Aerobic Respiration
the final electron acceptor in ETC is molecular oxygen (Ov2)
Anaerobic Respiration
the final electron acceptor is NOT Ov2 but an inorganic molecule. It gets less because only a part of the krebs cycle works, as well as only a part of ETC
Instead of oxygen they get nitrate, sulfate and carbonate
Fermentation
releases energy from oxidation from organic molecules , it does not use Krebs cycle or ETC. Uses an organic molecule as the final electron acceptor. Only energy made in glycolysis
lipase
turns a lipid into glycerol and fatty acids. The fatty acid goes through beta-oxidation and turns into acetyl CoA which is then used in the krebs cycle
Photosynthesis
conversion of light energy into chemical energy. Consists of two stages
Light-dependant reactions -atp synthesis and NADPH production
This is used to fix carbon ,
carbon fixation - turning carbon into organic molecules like sugars
Light - independent (dark) reaction - Calvin- Benson cycle
Photosynthesis styles
Photosynthesis styles
Oxygenic- oxygen is produced
Anoxygenic - atp is produced
Cyclic Photophosphorylation
the electrons released from chlorophyll return to the chlorophyll
Noncyclic photophosphorylation
used in oxygenic organisms, electrons do not return to chlorophyll, and are replaced with electrons from H2O
Calvin-Benson Cycle
how atp is made in plants , by using carbon fixation for the production of sugar
Chemotrophs
are organisms that use oxidation-reduction reactions of organic/inorganic compounds for energy
Phototrophs
mainly use light for the energy source, and the benson cycle to fix carbon dioxide
Photoheterotrophs -
get energy from light and carbon from organic molecules
Energy from light and carbon from organic molecules
Amphibolic pathways
are metabolic pathway that involve catabolic and anabolic functions
