Chapter 6 Flashcards
The fate of a chemical reaction is determined by
Direction and rate
First law of thermodynamics
Second law of thermodynamics
Energy can’t be created or destroyed but it can be converted from one form to another
Energy interconversions involve an increase in entropy
Free energy
The amount of energy available to do work or promote change
Spontaneous/ exergonic reactions do what and have what kind of free energy change
Release free energy and have a negative free energy change
Endergonic reactions have what kind of free energy change
Positive
Chemical reactions proceed until
The rate of formation of products equals the rate of formation of reactants
Exergonic reactions like the production of ATP are often
Couples to cellular processes that are endergonic
What % of proteins bind to ATP
20
EnZyme
A protein that speeds up the rate of a chemical reaction by lowering the activation energy (E a) needed to achieve a transition state
Enzymes recognize ____________ with a high specificity
Reactant molecules also called substrates
Confirmation changes cause substrates to
Bind more tightly to enzymes this is called induced fit
Each enzyme catalyzes reaction exhibits a
Maximal velocity
Km stands for
Substrate concentration when the velocity of the chemical reaction is half of the Maximal velocity value
Competitive inhibitors raise the
Noncompetitive inhibitors lower the
Km for the substrate
Maximal velocity
5 things that can affect enzyme function
Cofactors, coenzymes, prosthetic groups, pH, and temperatures
Prosthetic group
??
Altman and colleagues discovered the RNA subunit, RNase P is a ________
And definition of that word
Ribozyme, which is an RNA molecule that catalyzes a chemical reaction
Metabolism is
The sum of all chemical reactions in a living organism
Catabolic reactions def, 2 things they’re used for
Breakdown of large molecules into smaller ones. 1. Recycles organic molecules to reuse as building blocks for new molecule 2.large molecules are broken down to make energy intermediates like ATP
Redox reactions: definition and 1 thing they’re used for
Chemical reactions where electrons are transferred from one molecule to another.used to make energy intermediates like NADH
Anabolic reactions require an input of
Energy to synthesize larger molecules and macromolecules
Metabolic pathways are controlled by what 3 types of regulation
Genetic, cellular and biochemical
Example of a biochemical regulation
Feed back inhibition * get definition
Which enzyme is usually the target of cellular and biochemical regulation
The enzyme that catalyzes the rate-limiting pathway
Proteins in eukaryotes and archae are degraded by
Proteasomes
Lysosomes digest intracellular material through the process of
Atrophy
Reactions that release free energy are
Spontaneous and exergonic
Enzymes speed up reactions by
Lowering the activation energy necessary to initiate the reaction
A cell is breaking down carbs but stops once protease is added. This tells us the reaction is
Catalyzed by an enzyme
In biological systems, ATP functions by
providing the energy to drive endergonic reactions
In a chemical reaction where NADH is converted to NAD+ + H+, we’d say the NADH has been
Oxidized
Scientists identify the proteins that use ATP as an energy source by
Determining if the protein has a known ATP binding site.
In a chemical reaction if the inhibitor raises the km but not the v max, the inhibitor is
A competitive inhibitor and binds to the active site of the enzyme
Autophagy provided a way for cells to
Degrade entire organelles and recycle their components
