Flashcards in Lecture 7 Deck (71):
sum of all chemical reactions that occur within an organism
Hope for metabolism is that..
catabolic NRG covers anabolism NRG
2 classes of metabolism
reactions that GENERATE energy. breakdown of complex organic compounds into simpler ones
reactions that REQUIRE energy. biosynthesis or building of complex molecules from simpler ones
Energy is stored in the form of..
adenosine tri-phosphate (ATP)
The bonds between each of the 3 phosphate groups of ATP are..
very high energy (all NRG is stored here)
______ is key reason ATP stores so much NRG.
negative; negative oxygen wants to leave
What type of reactions generate ATP
ADP + Pi
AMP + Pi
AMP + PPi
What is waste product lost to form ATP
Oxidation reduction reactions reffered to as..
redox reactions. re= reduction ox= oxidation
is the loss of an electron from a molecule
is the gain of an electron by a molecule
LEO says GER
loss e- oxidation; gain e- reduction
Oxidation and reduction always occur...
In a redox reaction one molecule is...... and another molecule is...
oxidized (provides electrons) ; reduced (receives the electrons from the oxidized molecule)
Nicotinamide adenine Dinucleotide (NAD+)
Acts as an electron carrier. oxidized form, only room for 2 electrons
NADH + H
NAD + 2e- + 2H ---->
NADH + H
To get NAD reduced..
2 electrons are removed from the donor molecule and added to the recipient molecule
A + B are...
speed at which the chemical reaction proceeds
3 things can can be done in order to increase reaction rate
-adding an enzyme
lower the activation energy of a particular reaction
catalysts, cause more effective collisions, acts on a specific substrate
A particular enzyme catalyzes..
only on reaction
How does the enzyme lower the activation energy...
by positioning the substrate such that there is a greater probability that the reaction will take place
With an enzyme present reactions can occur..
up to 10 billion times faster than without an enzyme
breakdown of carbohydrates in order to release energy
Most common carbohydrate used by cells for energy is
2 processes can be used to catabolize glucose
occurs when oxygen is present, much more effective than fermentation
How many ATP are released in cellular respiration
occurs when oxygen is absent, less effective
How many ATP are released in fermentation
3 main stages of cellular respiration
-glycolysis (intermediate stage)
-krebs cycle (citric acid cycle)
-electron transport chain
splitting of sugar into smaller molecules, this reaction can occur in presence or absence of oxygen.
Gylcolysis occurs in a sequence of..
one glucose is converted into 2 molecules of pyruvic acid. only a small amount of NRG is released, 2 ATP and 2 NADH
2 molecules of pyruvic acid are prepared for entry into Krebs, oxygen is needed to produce this step
Intermediate step process
one carbon dioxide is removed from each (2) pyruvate, a CoA group is added to each of the 2 new formed carbon sugars. total of 2 NADH are formed
2 molecules of acetyl CoA are broken down into 4 CO2, requires oxygen
Where does the Krebs cycle occur
in the cytoplasm of bacterial cell and the mitochondria of eukaryotic cell
Total per glucose after krebs
10 NAPH, 2 FADH2, and 4 ATP
Electron transport chain
last step of aerobic respiration, occurs in the bacterial membrane, electrons from the NADH are transported through a series of electron carriers
Process of the electron transport chain
During each transfer of electrons, NRG is released and used to make ATP, 2-3 ATP are produced for each NADH that pass through the chain, end of the chain electrons are deposited to on oxygen forming water
The entire process of cellular respiration produces approximately..
32 ATP per glucose molecule\
occurs to produce NRG when oxygen is absent, produces much less NRG than aerobic respiration
Fermentation has... but no..
glycolysis; no krebs or ETC
How man ATP produced per glucose
2 main types of fermentation
-lactic acid fermentation
carried out by yeast/fungi and some bacteria. waste products of reaction are ethanol and carbon dioxide. 2 ATP are produces
Lactic acid fermentation
Pyruvic acid is converted into lactic acid, performed by many bacteria, can cause food spoilage and food production. 2 ATP are produced
Although glucose is the primary energy source used in bacteria they also use... (3 food catabolism)
polysaccharides such as starch are broken down into component sugars which are converted into glucose, the glucose then enters metabolic cycle beginning w/ glycolysis
lipids are broken into components (FA and glycerol) by the enzyme lipase, components then enter metabolic cycle via glycolysis or krebs
proteins are broken into component amino acids by enzymes (proteases), then enter into the metabolic cycle via glycolysis or krebs
The components of glycolysis and krebs usually serve as the..
starting point for the production go amino acids, lipids, and nucleotides
Components of glycolysis and krebs are referred to as..
Precursor metabolites can be..
one of carbon backbones in glycolysis like pyruvate, can used then to do glycolysis
Organisms can be classified based on their nutritional needs as..
-source of energy
-source of carbon
-Chemical energy - chemotrophs -organic OR unoriginal
-Light energy - phototrophs
-organic - heterotrophs (sugars)
-inorganic - autotrophs (CO2)
Most medically relevant bacteria are..
these organisms use light energy ti produce ATP and CO2 as carbon source through photosynthesis, includes some bacteria, all algae and plants
these organisms use light energy to produce ATP and obtain organic carbon from food, includes some bacteria
these organisms use chemical reactions to obtain energy and CO2, the chemical reactions involve reduced inorganic molecules (H2, H2S, CO), only done by some bacteria