CHAPTER 5 Flashcards
What is metabolism?
collection of controlled biochemical reactions that take place within a microbe; all chemical and physical workings of a cell
Anabolism vs catabolism
anabolic pathways build up macromolecules by combining simpler molecules, using energy in the process. Catabolic pathways break down macromolecules into simple component parts, releasing energy in the process. Catabolic reactions provide the energy needed for anabolic reactions
Oxidation and reduction reactions
many metabolic reactions involve the transfer of electrons from an electron donor to an electron acceptor
oxidation- giving electron
reduction- receiving electron
occur simultaneously
What are the types of phosphorylation?
substrate level, oxidative, photophosphorylation
What is phosphorylation?
inorganic phosphate is added to substrate
What is substrate level phosphorylation?
The transfer of phosphate to ADP from another phosphorylated organic compound
What is oxidative phosphorylation?
The use of energy from redox reactions to attach inorganic phosphate to ADP
What is photophosphorylation?
uses proton motive force to generate ATP
What are enzymes?
organic catalysts
What are the 6 categories of enzymes?
hydrolases isomerases ligases and polymerases lyases oxidoreductases transferases
What is the makeup of enzymes?
many protein enzymes are complete in themselves;
apoenzymes are inactive if not bound to nonprotein cofactors;
binding of apoenzyme and its cofactors yields holoenzyme;
some are RNA molecules called ribozymes
Factors effecting rate of enzymatic reactions
temperature, pH;
enzyme and substrate concentrations;
presence of inhibitors
What is the effect of an enzyme on chemical reactions?
the chemical reaction requires much less activation energy
What controls enzymatic activity?
activators- some enzymes activated when cofactor binds to allosteric site
What are enzyme inhibitors?
substances that block an enzyme’s activity, include competitive and noncompetitive
What happens during competitive inhibition of enzyme activity?
inhibitory molecules which are similar in shape to substrate molecule, compete for and block active sites on the enzyme;
reversible inhibition can be overcome by an increase in substrate concentration
location of glycolysis?
cytoplasm
input of glycolysis?
glucose, 2 NAD+, 2 ATP, 4 ADP + 4 P
output of glycolysis?
2 pyruvate, 2 NADH, 2 ADP, 4 ATP NET GAIN 2 ATP
location of krebs cycle?
.prokaryotes- cytosol
eukaryotes- matrix of mitochondria
input of krebs cycle?
2 acetyl-CoA; 6 NAD+, 2 FAD, 2 ADP + 2 P
location of ETC?
prokaryotes- cytoplasmic membrane
eukaryotes- inner mitochondrial membrane
input of ETC?
10 NADH, 2 FADH2
output of ETC?
10 NAD+, 2 FAD +, 6 H20, 34 ATP
Why is ATP described as the currency of the cell?
- It is the energy molecule that all cells need in order to do anything within the human body.
- How is the energy in ATP released?
- Hydrolysis, bonds break releasing energy. A phosphate is removed converting ATP to ADP plus energy.
How is the energy in ATP released?
- Hydrolysis, bonds break releasing energy. A phosphate is removed converting ATP to ADP plus energy.
What type of bonds have to be broken to release the energy in ATP?
one phosphate bond
Describe the relationship between energy stored in food and ATP.
it is labeled as potential energy, but has to broken down through cellular respiration to be used.
How does the energy content in carbohydrates, lipids, and proteins differ?
carbs are used the most, lipids make the most but cant be easily broken down, and proteins are rarely used
How are ATP and ADP related?
3 phosphates to 2 phosphates
What is the function of cellular respiration?
releases stored energy in glucose molecules and converts it into a form of energy that can be used by cells
Explain the difference between aerobic and anaerobic respiration.
aerobic- oxygen serves as final electron acceptor, requires oxygen. Anaerobic- molecule other than oxygen serves as final electron acceptor, does not require oxygen
What is the equation for cellular respiration?
C6H12O6 + 6O2 6CO2 + 6H2O
Cells produce the most energy in the presence of which molecule?
ATP
What is the total number of ATP made for each molecule of glucose during respiration?
38
Where does Glycolysis take place?
cytoplasm
What molecules are needed to start Glycolysis (reactants)?
glucose, 2NAD+ 2 ATP, 4 ADP + 4 P
What are the products of Glycolysis?
2 pyruvate, 2 NADH, 2 ADP, 4 ATP
How is the net amount of ATP made in Glycolysis different from the total number of ATP produced?
it’s what is gained after making up for the 2 input ATP
What is the main function of Glycolysis?
to break down glucose into 2 molecules of pyruvate
Where does the Krebs Cycle take place?
in cytosol for prokaryotes, in the matrix of mitochondria for eukaryotes
What molecules are needed to start the Krebs Cycle (reactants)?
2 acetyl-CoA, 6 NAD+, 2 FAD, 2 ADP + 2 P
What are the products of the Krebs Cycle?
4 CO2, 6 NADH, 2 FADH2, 2 ATP
Describe how the Krebs Cycle and Glycolysis are related.
Glycolysis is the first step involved in the process of respiration, Krebs cycle is the second. Both have aim of fulfilling energy requirement of body
What is the role of NADH and FADH2?
NADH and FADH2 transport electrons in glycolysis and krebs cycle to the electron chain.
What is the name of the 6 Carbon molecule that forms when Acetyl-CoA joins 2 Carbons to a 4 Carbon molecule?
Pyruvic acid
What is the main function of the Krebs Cycle?
To transfer high energy electrons to the electron transport chain
Where does the Electron Transport Chain take place in Prokaryotes v/s Eukaryotes?
Prokaryotes- cytoplasmic membrane; eukaryotes- inner mitochondrial membrane
What molecules are needed to start the Electron Transport Chain (reactants)?
10 NADH, 2 FADH2
What are the products of the Electron Transport Chain?
10 NAD+, 2FAD+, 6H2O, 34 ATP
Describe how the Electron Transport Chain and Krebs Cycle are related.
all a working system to make ATP and both require oxygen
Explain the functions of electrons, hydrogen ions, and oxygen in the ETC.
Electron go across the inner membrane of mitochondria, Hydrogen ions go across to outer part of membrane and come back through ATP Synthase and combine with ADP to for majority of ATP, then Hydrogen combines with Oxygen and is released as a waste product
What is the role of ATP synthase in the ETC?
Allow Hydrogen ions to pass back through and combine with ADP to form ATP
What molecule in the final electron acceptor at the end of the ETC?
oxygen
What is the main function of the ETC?
Primarily used to send protons across the membrane into the intermembrane space
Where does anaerobic respiration take place?
cytoplasm
When does anaerobic respiration take place?
when no oxygen is required
Describe how fermentation and glycolysis are related.
fermentation uses glycolysis to start its process
What are the two types of fermentation?
lactic acid and alcoholic fermentation
How many molecules of ATP are produced in fermentation?
2
What are some real world applications for each type of fermentation?
build up in muscles, cheese, wine, yogurt, etc
What are ways that aerobic and anaerobic respiration are similar? How are they different?
both use glycolysis, but presence of oxygen separates the processes
What is pyruvic acid changed into in alcoholic fermentation?
acetaldehyde & CO2
Organism in alcoholic fermentation
wine, beer
What is pyruvic acid changes into in lactic acid fermentation?
lactic acid
Organism in lactic acid fermentation
yogurt, soy sauce, cheddar cheese
What are the two stages of photosynthesis?
light dependent and light independent
Starting molecule for light dependent?
H2O (sunlight)
Starting molecule for light independent?
ATP, NADpH, CO2
product of light dependent?
ATP, NADPH, O2
product of light independent?
glucose
What is the general chemical equation of photosynthesis?
6 CO2 + 6 H20 –> C6H12O6 + 6 O2 ^ (thats an up arrow) *regular arrow between reactant and products is light and pigment)
Total amount of ATP made from breakdown of one glucose molecule in aerobic respiration?
38
What is the chemiosmotic theory?
use of electrochemical gradients to generate ATP, called oxidative phosphorylation because proton gradient is created by oxidation of ETC components; total of 34 molecules formed from one molecule of glucose
Total amount of ATP made from fermentation?
2
What makes fermentation special?
fermentation pathways provide cells with alternative source of NAD+. Cells require constant source of NAD+ that cannot be obtained with just glycolysis and krebs cycle
