ch.4 cellular respiration Flashcards
What are the two types of metabolic pathways and reactions?
anabolism and catabolism
Define anabolism
small molecules are built up into larger ones; requires energy (ATP)
define catabolism
larger molecules are broken into smaller ones; releases energy
define cellular metabolism
sum of all chemical rxns in a cell
what does anabolism provide materials for?
cell maintenance, growth, and repair
what is the main type of anabolic process? describe in
dehydration synthesis; joins simple sugar molecules to form larger molecules of gylcogen
what type of organic molecules can dehydration synthesis be used for?
-carbohydrates (simple sugar to glycogen)
-lipids (glycerol and fatty acids to triglyceride)
-protein (joining amino acids)
-nucleic acids
what type of bonds connects amino acids to form proteins?
peptide bond
what is the main type of catabolic reaction? describe it
hydrolysis; decomposes carbohydrates, lipids, and proteins
what is a product in all dehydration synthesis rxns but a reactant in all hydrolysis rxns?
water
hydrolysis is the ___ of dehydration synthesis
reversal
why doesn’t hydrolysis occur automatically?
-water soluble substance will dissolve in water but won’t undergo hydrolysis
-the process requires enzymes
why might some metabolic rxns not be reversible?
the enzyme needed for the anabolic rxn may be different than the ezymes needed for the catabolic rxn
true or false
catabolism and anabolicm must be controlled so that the breakdown or energy releasing rxns occur at rates adjusted to the requirements of the build up or energy utilizing rxns
true
define intermediary metabolism, primary metabolism, and secondary metabolism
-process that obtain, release, and use energy
-products of metabolism essential to survival
-not essential, but may provide advantage (plants)
what is the main job of enzymes
controling the rate of chem rxns
true or false
energy releasing rxns don’t need to occur at rates to balance energy utilizing
false
metabolic rxns require ___ energy before they process
activation
in a lab what is used to increase the rate of rxns?
heat
most enzymes are globular proteins that catalyze specific chem rxns by …
lowering activation energy
how are most enzymes named?
dervided from the names of the substrate, with the suffix -ase
define an activation site. how does this help with the chem rxn
-a region of enzyme that temporarily combines with specific part of a substrate, forming an enzyme-substrate complex
-this interaction strains chem bond in substrate so that the chem rxn requires less energy
what does the rate of enzyme-catatlyzed rxns depend on?
-rxn is faster if rate of enzyme or rate of substrate increases
what is critical to an ezymes function? what can damage this?
-their configuration (shape)
-excessive heat, radiation, electricity, certain chemicals, fluids with extreme pH values
define denature
inactivation of an enzyme
how do enzyme-catalyzed rxns form metabolic pathways?
the product of one rxn is the reactant in another rxn. this process continues to happen
define metabolic pathways
lead to the synthesis or breakdown of particular biochemicals
what does a regulatory enzyme do in metabolic pathways?
sets the rate for the entire sequence of rxns
when enzymes don’t work at high substrate concentrations, it is a … Where are these enzymes located in the metabolic pathways
-rate limiting enzyme
-usually first
how does negative feedback relate to metabolic pathways?
in some pathways that product inhibits the rate limiting enzyme. accumulating product inhibits the pathways