30 terms

Chapter 6


Terms in this set (...)

All an organism's chemical reactions:
Cellular process requiring multiple steps:
Metabolic pathways
Building large molecules
anabolic pathways
Breaking down complex molecules:
catabolic pathways
Food represents ________________ energy
When you move, you convert ___________energy into __________ energy
potential, kinetic
What happens to some of the energy from your food when you move?
metabolic waste heat
In a spontaneous reaction, free energy always _____________
How do exergonic and endergonic reactions differ?
exergonic.-releases free energy
endergonic.-requires free energy
What becomes of free energy at equilibrium?
no change
Living things are ___________ systems that reach equilibrium when?
open, never
How does a cell power an endergonic (anabolic) reaction
energy coupling
What is the most common coupled exergonic reaction?
ATP hydrolysis
How can a cell charge or energize a protein?
Energy from catabolism is used to:
Make ATP
Energy for cellular work comes from:
Platinum speeds hydrogenation of oils without being consumed, it is a:
Most enzymes are __________________, but some are ____________
Proteins, Ribozyme
How does an enzyme speed up a reaction?
Lowers activation energy
How does induced fit model differ from the old "lock and key" model?
it slightly alters the shape
What would be the substrate for a DNase enzyme?
How does the enzyme active site bind substrate?
hydrogen and ionic bonds
How does heat affect enzyme activity?
denatures the protein
How does cold affect enzyme activity?
slows it down
How do pH changes affect most enzymes?
to acidic, denatures most enzymes
Competitive or noncompetitive inhibitor: Penicillin binds a bacterial enzyme's active site
Competitive or noncompetitive inhibitor: Silver binds many enzymes but not at active site
Competitive or noncompetitive inhibitor: The antibiotic sulfanilamide is chemically similar to PABA, an enzyme substrate
Binding of cyclic AMP "opens" the active site of hexose phosphatase, it is an ___________________
allosteric Activator
How does a cell with ample isoleucine stop isoleucine production?
feedback inhibition