Chapters 4 & 22partA Flashcards
There are 2 basic types of reactions in cells. By definition those that release energy are called what? Those that require the input of energy are called what?
exergonic reaction - releases energy
endergonic reaction - require the input of energy
Define kinetic energy.
energy of motion
Define potential energy.
stored energy (chemical bonds)
Nearly all enzymes are what type of molecule?
proteins
The location on an enzyme where the reactants (substrates) interact is called the what?
active site
Generally speaking can an enzyme catalyze a diversity of reactions or only catalyze 1 specific reaction?
1 specific reaction
When an ATP molecule is “used” to power a chemical reaction it is converted into: (list the products)
ATP —> ADP + Pi + energy
Define the term catabolism as it applies to metabolism.
Reactions that release energy through the breakdown of large biomolecules.
Define the term anabolism as it applies to metabolism.
Energy-utilizing reactions that result in the synthesis of large biomolecules.
Define metabolism as it applies to a person or a cell.
All chemical reactions that take place in an organism.
What do metabolic reactions do?
- Extract energy from nutrient biomolecules (such as proteins, carbohydrates, and lipids)
- Either synthesize or break down molecules.
Write out the complete chemical equation that describes the oxidation of glucose.
C6H12O6 + 6O2 —–> 6CO2 + 6H2O + 30ATP
List the starting substrate of glycolysis.
Starting substrate - glucose
Where in the cell does glycolysis take place? Is this and advantage or disadvantage?
Cytoplasm
Advantage because it’s fast since it is made where it is used.
What is the total net yield of ATP from glycolysis?
2 ATP
Is glycolysis an aerobic or anaerobic process?
Anaerobic because it does not require oxygen.
Describe the fate of pyruvate in a cell when oxygen levels are low. Be sure to include all the molecules involved (including the enzyme).
The pyruvate will be converted to lactate by the enzyme lactate dehydrogenase. It is then used by the myocardial cells and the liver. If it builds up it is exported to the blood which drops the pH. (acidosis)
Define anaerobic as it applies to cellular reactions.
A reaction that does not require oxygen
Glycolysis (all by itself) produces what? (include numbers)
2 pyruvate
What is the starting substrate of the citric acid cycle?
Acetyl CoA
How many ATP molecules are generated by “1 turn” of the citric acid cycle? What other molecules are generated (include numbers)
1 ATP
3 NADH
1 FADH2
Where exactly does the citric acid cycle occur?
in the mitochondria matrix
Where exactly does electron transport and oxidative phosphorylation take place?
mitochondria on innermembrane and intermembrane space
What powers the hydrogen pumps in electron transport? List the molecules.
high energy electrons from NADH and FADH2 to power hydrogen pumps.
The enzyme that actually produces ATP during oxidative phosphorylation is called what? For a glucose molecules about how many ATP does it produce?
ATP Synthase
For a glucose molecule it produces about 30 ATP
What is the fate of the electrons during electron transport?
each pair of electrons released combines with two H+ (hydrogen atom) and an O2 (oxygen atom) creating a molecule of water. H2O
2H + O2 + H2O
Where is oxygen used in electron transport?
final e- acceptor
Roughly how many ATP’s can be generated from a triglyceride?
about 300
Define glycolysis and list the specific substrates and products. Classify as either anabolic or catabolic.
glycolysis - the breakdown of glucose by enzymes, releasing energy and pyruvic acid.
Substrate - Glucose
Product - Pyruvate
Catabolic
Define gluconeogenesis and list the specific substrates and products. Classify as either anabolic or catabolic.
gluconeogenesis - the synthesis of glucose from noncarbonate sources, such as amino acids and glycerol.
Substrates - glycerol, pyruvate, amino acids, lactic acid
Product - glucose
Anabolic
Define ketogenesis and list the specific substrates and products. Classify as either anabolic or catabolic.
ketogenesis - formation of ketone bodies, an alternative energy source, from acetyl-CoA.
Substrates - acetyl-CoA
Product - Ketone bodies
Anabolic
Define beta-oxidation and list the specific substrates and products. Classify as either anabolic or catabolic.
beta-oxidation - breakdown of fatty acids to acetyl-CoA
Substrates - fatty acids
Product - acetyl-CoA
Catabolic