BIO 140.01 - Module 1-3: Energy & Metabolism

Metabolism

Sum of all chemical reaction

False; to another form of energy

T or F: Metabolism converts energy to work

Kinetic to Potential

Describe the energy transfer: Sunlight → Glucose

Potential to Kinetic

Describe the energy transfer: Glucose → Metabolic Processes

90

% of energy lost as heat with each energy transfer in the biosphere

Catabolic

Identify the reaction: Carbohydrates, Fats, Proteins to H2O, CO2, NH3

Anabolic

Identify the reaction: Amino Acids, Sugars, Fatty Acids, Nitrogenous bases to Proteins, Polysaccharides, Lipids, Nucleic Acids

Catabolic

Identify the reaction: Energy-yielding nutrients to energy-poor end products

Anabolic

Identify the reaction: Precursor molecules to cell macromolecules

False

T or F: Catabolic processes are oxidative and endergonic

False

T or F: Anabolic processes are oxidative and exergonic

Carrier molecules

These moleculares temporarily store energy in easily exchangeable form when activated and responsible for carrying energy to parts of the cell that needs to perform work

True

T or F: NADPH is a form of carrier molecule

True

T or F: ATP is a form of carrier molecule

Coupled reactions

Type of reaction process that explains how catabolic reactions release energy that power anabolic reactions

Catabolic

Identify the reaction: Food molecule is turned into an oxidized food molecule in an energetically favorable reaction

Anabolic

Identify the reaction: Molecule available in the cell is turned into the molecule needed by the cell in an energetically unfavorable reaction

ATP

Stores energy in a chemical bond

False

T or F: ATP diffuses slowly throughout the cell

True

Energy as ATP is temporary

True

T or F: ATP hydrolysis can be used to separate charges across a membrane to create potential energy.

False

T or F: ATP hydrolysis prevents solutes from concentrating within a compartment.

False

T or F: Energetically unfavorable reactions do not rely on ATP hydrolysis to proceed.

True

T or F: ATP hydrolysis is involved in muscle contractions by help sliding filaments

True

T or F: ATP hydrolysis can create binding sites on a protein

Thioester bond

In what bond in Acetyl-CoA is the energy stored in

False

T or F: Acetyl-CoA releases the CoA group during the Krebs cycle

False

T or F: NADPH is an oxidizing agent

Oxidative Phosphorylation

Reaction carrier molecules involved in the electron transport chain undergo

Electrons, Hydrogens

NADH, NADPH, FADH2 carry their energy in what groups

False

T or F: Cells exists as a thermodynamic non-equilibrium closed system

Steady state

Concentration of molecules remains constant but individual reactions are not at equilibrium

False

T or F: Cells will always have higher ADP than ATP because it continually takes in energy and nutrients

True

T or F: Despite ATP always being at a higher concentration, cells continually use ATP to drive cellular processes. The moment they stop using ATP, cells die.

False

T or F: Rates of reactions in cells are constant and stable

True

T or F: A cell only approaches equilibrium when it is dead

True

T or F: Reactions in the metabolic pathways of the cell are connected and sequential

Enzymes

Proteins or catalytic machineries that facilitate and speed up cellular processes

False

T or F: Only some protein molecules possess a binding site

Ligand

This molecule binds to the protein

False

T or F: Ligands bind to the protein using covalent bonds

Active site

Term for binding site in enzymes

Substrate

Term for ligand in enzymes

True

T or F: The presence of binding sites is dependent on the enzyme’s functional conformation

False

T or F: A protein can maintain its function even after undergoing denaturation

Lock and key model

Model that describes the he active site of the enzyme and the substrate have complementary shapes

Induced fit model

The active site of the enzyme changes its shape slightly to accommodate a better fit with the substrate.

Induced fit model

More widely accepted as it considers the interaction between enzyme and substrate

False

T or F: Lysozyme stays on the polysaccharide chain after cleavage

True

T or F: Enzymes do not make a process spontaneous. They just lower the activation energy of the reaction.

False

T or F: Enzymes can only make a reaction go forward.

True

T or F: Enzymes only recognize and bind to specific substrates

True

T or F: Enzymes are reused and not altered during reactions

False

T or F: Reactions, especially those with high AE, require large amounts of enzymes

Activation energy

Free energy required to attain transition state

False

T or F: Enzymes provide the amount of energy required for the reaction to occur

True

T or F: Enzymes can orient two substrates in closer proximity to each other to drive a reaction forward

False

T or F: Cofactors bind to substrate and rearrange electrons to create partial charges to favor a reaction

True

T or F: Enzymes can strain the substrate towards its transition state

False

T or F: Coenzymes are inorganic, often metal ions, used to aid enzymes

False

T or F: Organic non-protein components, such as retinal, are called cofactors

True

T or F: Heme uses Fe, a cofactor.

Vmax

maximum rate of reaction when all enzyme active sites are saturated with the substrate

Turnover number

number of substrate molecules that can be converted by one enzyme per unit of time

True

T or F: Vmax is limited by the turnover number

True

T or F: Turnover number is independent of the substrate concentration

Km

substrate concentration that gives half-maximal velocity

Km

this measures the enzyme-substrate affinity

False

T or F: Higher Km means that there is higher substrate affinity, or that less substrate is needed to reach 0.5 Vmax

True

T or F: An enzyme with lower affinity for substrate will have a higher Km

False

T or F: Enzymes can function in any pH level as long as it fits the substrate

True

T or F: Increasing temperature can increase enzyme activity by increasing the energy

False

T or F: Extremely high temperatures create increased enzyme activity

True

T or F: The limiting factor in the reaction is not the enzyme's ability to convert the substrate into the product but rather how often the substrate collides with the enzyme

Multi-enzyme complexes

Systems of enzymes which function sequentially by catalyzing consecutive reactions

Multi-enzyme complex

Pyruvate Dehydrogenase Complex is a form of ___

Irreversible Inhibition

The inhibitor permanently binds to the enzymes in a covalent bond which changes the enzyme chemically

Competitive inhibition

Binds to the active site of the enzyme, directly displacing and preventing substrate from binding

Non-competitive inhibition

Binds to an allosteric site, causing the active site to change its shape, preventing substrate from binding.

Substrate

Competitive inhibition can be overcome by increase the ___ concentration

False

T or F: Non-competitive inhibition can also be overcome by increasing the substrate concentration

True

T or F: Non-competitive inhibition can be overcome by elution or breakdown of the inhibitor

False

T or F: Competitive inhibition increases Vmax

True

T or F: Competitive inhibition increases Km

False

T or F: Competitive inhibition has no effect on enzyme-substrate affinity

False

T or F: Noncompetitive inhibition increases Vmax

True

T or F: Noncompetitive inhibition has no effect on Km

Allosteric modulation

Regulation by reversible binding with other molecules

True

T or F: Binding of one ligand to the allosteric site affects the conformation of the active site in allosteric modulation

False

T or F: Binding of a ligand to an enzyme in allosteric modulation is irreversible

Positive regulation

The presence of one ligand in its binding site encourages the binding of the other to its respective site.

Negative regulation

The presence of one ligand in its binding site interferes with the binding of the other to its respective site.

Feedback inhibition

The end-product of a single biosynthetic pathway (Z) inhibits the first enzyme that is unique to its synthesis; a form of negative regulation.

Multiple feedback inhibition

Type of inhibition when biosynthetic pathways for four different amino acids are inhibited by each amino acid specific to its own synthesis

GTP-binding proteins

Small molecules that bind to proteins and activates them

False

T or F: Protein is inactive when GTP is bound to it and active after it undergoes hydrolysis and turns into GDP

True

T or F: GDP dissociation is a slow reaction

GTPase-activating protein

Enzyme that helps induce GTP hydrolysis

GAP

Guanine nucleotide exchange factors catalyzes the dissociation of GDP, which makes it a form of __

Red alpha-helix

Hydrolysis of GTP to GDP in EF-tu protein causes a shift in conformational change in ____ which opens up the protein to release tRNA