Metabolism

Question 1

metabolism definition

Answer 1

totality of an organism’s chemical reactions
an emergent property - result from various interacting components and not present in the invididual components themselves

Question 2

catabolic vs anabolic

Answer 2

catabolic - breakdown process releasing energy (respiration)
anabolic - consume energy to build molecules - protein synthesis

Question 3

bioenergetics

Answer 3

the study of how organisms manage their energy resources

Question 4

thermal energy

Answer 4

is kinetic energy due to motion of particles

Question 5

energy definition

Answer 5

capacity to cause change and some forms can do work
can be converted from one form to another
cannot be created nor destroyed

Question 6

potential energy definition
chemical energy definition

Answer 6

energy matter possesses due to location or structure
potential energy available for release in chemical reaction

Question 7

different types of systems in thermodynamics

Answer 7

isolated - no exchange of energy or matter
closed - no exchange of matter, but energy can exchange
open - exchange of energy and matter (ex. organisms)

Question 8

entropy

Answer 8

increases with every energy transfer
heat released increased entropy of the universe

Question 9

structural order

Answer 9

biological order is a characteristic of living things
requires energy input to create order

Question 10

change in free energy equation

Answer 10

∆G = ∆H - T∆S

Question 11

enthalpy
entropy

Answer 11

∆H - change in total energy available to do non mechanical work (heat)
∆S - change in entropy (disorder, unable to do work)

Question 12

spontaneous processes

Answer 12

occur without energy input
-∆G means free energy decreases, increase entropy
stability of system is increased
moves towards equilibrium
energy released can be harnessed to do work

Question 13

free energy

Answer 13

energy that can do work at uniform pressure and temp
high free energy = unstable, large energy payoff when released
exergonic - release of free energy
endergonic - consumption of free energy (non spontaneous)

Question 14

types of cellular work

Answer 14

chemical work - non spontaneous building of molecules
mechanical work - movement or transport (pumping ions against concentration gradient)

Question 15

ATP structure

Answer 15

3 phosphates - ribose (5C ring) - adenine base
modified nucleotide

Question 16

reaction to break down bonds btwn phosphates in ATP

Answer 16

hydrolysis - addition of water to break bond, release energy and Pi
release of energy comes from transformation from higher to lower energy state

Question 17

how does ATP drive endergonic reactions?

Answer 17

by phosphorylation into phosphorylated intermediate

Question 18

catalyst vs enzyme

Answer 18

catalyst is chemical agent that speeds up reaction without being consumed
enzyme is a protein catalyst

Question 19

initial energy needed to start a chemical reaction

Answer 19

activation energy Ea
can be supplied from thermal energy, enough energy absorbed and molecules will go to unstable transition state, breaking bonds allowing them to reform

Question 20

enzymes do not

Answer 20

change free energy, only lower Ea (speed up rxns that would occur eventually)

Question 21

induced fit

Answer 21

brings substrate chemical groups of active site closer together to enhance ability to catalyze reaction

Question 22

ways that enzyme active site lowers Ea

Answer 22

orientation of substrates, straining bonds, favorable microenvironment and covalent bonding of substrate
products have reduced affinity for active site

Question 23

competitive inhibitor

Answer 23

mimics substrate competes for active site so substrate can’t bind

Question 24

noncompetitive inhibitor

Answer 24

binds to non-active site, causes conformational change that decreases efficacy of active site

Question 25

altered amino acids from mutations in genes can

Answer 25

alter enzyme specificity
new environmental conditions can give rise to new forms of enzymes

Question 26

regulation of enzymes

Answer 26

on/off gene expression of enzymatic genes
on/off activity of enzymes
negative feedback

Question 27

allosteric regulation
activators/inhibitors

Answer 27

can inhibit or stimulate enzymatic activity
binds to one site affecting protein function at another site
often contain multiple polypeptide subunits
activators - stabilize active form of enzyme
inhibitor - stabilize inactive form of enzyme

Question 28

co-operativity

Answer 28

can amplify enzymatic activity by priming enzyme to be more effective
binds to one active site which affects catalysis of different active site (allosteric)

Question 28

specific locations of enzymes

Answer 28

structural components can be enzymes
enzymes in specific organelles for their specific function