Exam 2 Flashcards
What is the sum of chemical reactions inside a cell?
Metabolism
What is a catabolic reaction
breaks down complex molecules into simpler ones (hydrolysis)
What is an anabolic reaction?
build up molecules from simpler ones
Which reaction releases energy?(exergonic)
catabolic
which reaction requires energy? (endergonic)
anabolic
What is energy?
the capacity to do work
What is the difference between kinetic and potential energy?
kinetic is movement (ex: thermal E)
potential is position( ex: chemical E)
What is the study of energy?
thermodynamics
what is the first law of the conservation of E
the amount of energy in the universe is constant, energy cannot be created or destroyed
what is the second law of the conservation of E
every energy transformation involves an increase in entropy(s) = the amount of disorder in the universe.
is water evaporating an increase in entropy?
yes
what process creates a decrease in entropy because it must input energy?
anabolic
what does chemical reactions in cells do?
power life
What is gibbs free energy
the energy that is available to do work
Change in Delta “G” =?
Gproducts- Greactants types: if negative( - ) releases E, spontaneous, exergonic if positive( + ) requires energy, non. spon. endergonic if 0 equilibrium, cannot do work.
what do spontaneous reactions drive?
non spon reactions
ex.) catabolic reactions release E–> feeds into anabolic rxns that require E
Delta G tells you nothing about what?
the speed of the reactant
What is activation Energy?
- the Energy needed to reach transition state.
- It breaks old bonds and makes new ones
E,activation = G trans st. - ___________?
G reactions
The larger the activation energy the _________the reaction
slower
Enzymes are catalyst, what do they do?
they speed up a reaction Without being consumed.
Do enzymes change the delta G value?
NO
Do enzymes reduce Activation energy?
YES
Fig 3.13
look up
How do enzymes lower Activation energy?
the enzymes active sight binds a reactant(substrate) through multiple weak/temp interactions that form through spontaneous exergonic rxns that feed into lowering Eact.
- this accounts for enzyme specificity
Metabolic pathways.
- ) ______ and _________ pathways consist of series of chemical reactions.
- ) The____ of one reaction is the ________ for the next reaction?
- ) how does a cell maintain a constant environment with all this chem activity?
- catabolic, anabolic
- product, substrate
- regulation of enzymes
How do you regulate the metabolism by regulation of Enzymes?
- ) change the amount of enzyme
2. ) change the activity of enzyme
which inhibitors bind permenantly to the active site of an enzyme and completely shut off the enzyme activity?
irreversible inhibitors
which enzymes bind to an enzyme through temporary, non- covalent interactions?
reversible inhibitors
Which inhibitor is similar in shape of the substrate and blocks it from binding?
competitive
which inhibitor does not bind to an active sight and when it binds to the enzyme it cuases the enzyme to change shape?
What non- competitive
What does Allo/steric mean?
Allo= different
steric=shape
Allosteric regulation
- which regulation is non-competitive inhibitors?
- which is allosteric activators?
- negative regulation
2. positive regulation
How do regulator molecules bind?
through non covalent and covalent attachment
non covalent = attaching a larger regulatory molecule GTP & ATP
covalent = attaching a phosphate enzyme
what Is feedback inhibition?
product of the reaction inhibits the enzyme. (competitive inhibition)
What are the regulations of the environment?
pH. and temperature
what happens in pH inhibition?
all enzymes have an optimum pH
higher or lower enzymes can affect the enzyme and make it unfold and lose structure
what happens in Temperature inhibition?
enzymes have an optimum temp.
to high= denature
to slow= slows enzyme
co factors
help enzyme do its job, non protein partners. Metal ions are z2+ Fe2+ Fe3+
they are large molecules that temporarily bind to the enzyme
prosthetic groups - bind to enzyme permanantly
Chemical regulation is often the form of__________
inhibitors
When you determine the shape of the substrate you should first______________
determine the shape of the inhibitor
you can observe a _________ by adding more_______
competitive inhibitor, substrate
___________ inhibitor can be over come by the addition of more substrate
non competitive
in __________- we break _______________– which result in an explosion of energy
digestion, covalent bonds
What are the three steps of cell theory?
- cells are the fundamental (smallest) units of life
- all living things are made of cells
- all cells come from pre existing cells
1600 microscopes were invented.
- ) Schleiden (botanist) honored with____________
- ) Schwan (physiologist) described______________
connection as cells being living
2 several different types of animal cells
Why are cells small?
maximize SA: Volmume ration
What does surface area on a cell determine
import and export rates
what does volume determine on a cell membrane?
metabolic activity
All cells have
plasma membrane, cytosol, DNA, ribosomes
ribosomes can be ______,_________,__________________
free, bound, made of rRNA + several small proteins
proteins are referred to as scaffolding.
What does rRNA do? what do proteins hold together?
synthesizes proteins. ribosomes
what are prokaryotic features?
nucleoid cytoskeleton= protein filaments only in some:(below) cell wall= peptidoglycan capsule= slimy layer of carbs flagella = flapping appendage