BIO 120 LECTURE 6 Flashcards
what are the 3 different forms of energy?
Kinetic energy
potential energy
chemical energy
KINETIC ENERGY?
Energy possessed by an object because of motion.
ex:waterfall, falling rock
POTENTIAL ENERGY?
Form of stored energy, the capacity to perform work
ex-water behind dam
fossil fuels
name a fossil fuel in form of hydrocarbon?
gasoline
name a fossil fuel in form of carbon?
coal
when is the chemical energy stored ins fossil fuels released?
when they are burned into combustion engine.
all chemical molecules store________.
energy
why do different molecules have various potential energy?
due to the arrangement of their atoms
what is thermodynamics or thermodynamic system?
a branch of physics concerning the study of energy, conversion of energy between diff forms and the ability of energy to do work.
FIRST LAW OF THERMODYNAMICS?
LAW OF ENERGY CONSERVATION
WHAT DO U MEAN BY LAW OF ENERGY OF CONSERVATION?
The total amount of energy in the universe remains constant
energy can be changed one ______ to another?
form
SECOND LAW OF THERMODYNAMICS?
LAW OF ENERGY CONVERSIONS
THE LAW OF ENERGY CONVERSIONS
Reducing the order of universe, increasing its entropy
what do u mean by RANDOMNESS in thermodynamic?
amount of disorder in a system.
what is the spontaneous direction of energy flow acc to 2 law of thermodynamics?
rich energy to less organized (less energy)
the amount of “lower quality” energy in the universe is ____________?
increasing
some energy is always lost as ________?
HEAT
What is imp for energy conversions?
Energy input
what happens to a organized system without energy input?
it gets disorganized
CELLULAR METABOLISM?
Sum of chemical activities in a living cell.
_______ increases rate of chemical reaction without the need For an increase in ________.
ENZYMES, TEMPRATURE
enzymes are a group of _________.
catalysts
In a cell, what group of enzymes catalyzes the removal of a phosphate group from a range of molecules.
PHOSPHATASES
In the presence of phosphatase the removal of phosphate takes how much time?
10 milliseconds
_________ radiation is also a form of energy.
ELECTROMAGNETIC
What happens to the energy level of electrons on gain of energy?
moves to higher energy level i.e. further away from nucleus.
what happens to electrons on loss of energy>
moves to lower energy levels, closer to nucleus.
what is the energy level near nucleus?
near nucleus,
First energy level(lowest energy)
second energy level
Third energy level (Highest energy)
Everything outside the system is called the ___________.
Surrounding
Isolated system?
does not exchange matter or energy
Closed system?
exchange energy, not matter with its surroundings
Open system
both energy and matter can move freely b/w the system and surroundings
The higher the waterfall, The __________ kinetic energy it will possess.
more
what is entropy
tendency of energy to become dispersed or spread out is defined as entropy
SPONTANEOUS PROCESS?
A process that occurs without a constant input of energy
entropy is measure of __________ or ____________.
disorder or randomness
what happens if entropy of system and surrounding increase?
energy and matter will becomes more spread out
ENTHALPY?
Heat content of a system (ΔH)
exothermic reaction?
process that releases heat
ΔH is negative
endothermic reaction?
system taking up heat from its surroundings
ΔH is positive
example of exothermic reaction?
burning of wood
example of endothermic reaction?
melting of ice
what technique is used to measure change in heat of a chemical reaction?
calorimetry
how does change in enthalpy and entropy influences the spontaneity of process?
1.reaction-spontaneous-exothermic
2.entropy of products greater than entropy of reactants
energy spreads our more readily when matter undergoes _________ changes.
phase
Gibbs free energy?
amount of energy that is actually available in a system to do work (G) when temp and pressure are uniform throughout the system.
what are the two different Metabolic pathways?
ANABOLISM, CATABOLISM
what do u mean by the term metabolic pathways?
sequences of enzyme-catalyzed reactions.
Define anabolism? and one example
synthesis of complex molecules from simpler substances
ex-photosynthesis
define catabolism? and give one example
larger molecules are broken down into smaller ones.
ex-cellular respiration
what do u mean by chemical reactions?
change in composition or distribution of atoms of a substance, making or breaking of chemical bonds
the total bond energy in a chemical reaction is essentially equivalent to the the total ______ energy of the molecule.
potential
change In free energy?
ΔG = G products- G reactants
change in Gibbs free energy is a measure of how ____________ a process is
spontaneous
spontaneous reaction is one in which the free energy of the ___________ is less than that of __________.
products, reactants
what is a spontaneous process called?
exergonic process
what is a non spontaneous process called?
endergonic process
what is the point of equilibrium?
point at which their is no longer any overall change in the concentration of the products and reactants.
Rate of forward reaction=rate of backward reaction
livings cells can never reach ___________
chemical equilibrium
what is the value of ΔG at chemical equilibrium?
ΔG = 0
METABOLISM?
collection of all the chemical reactions present within a cell or organism
Anabolic pathways aka __________
Biosynthetic pathways
differentiate catabolic and anabolic pathway as endothermic and exothermic?
Catabolic pathway-exothermic-energy release
Anabolic pathway-endothermic-require energy
what do you mean by ENERGY COUPLING REACTION?
use of energy released from exergonic reactions to drive essential endergonic reactions.
HYDROLYSIS REACTION?
Terminal phosphate bond is broken, resulting in the formation of adenosine diphosphate and a molecule of inorganic phosphate.
is energy released when bonds break?
🙅🏻♀️
_____________ is required to break bonds.
ENERGY
Is energy released on formation of new bonds.
☑️
ATP BREAKDOWN IS A _________ PROCESS.
a.ENDERGONIC(ns)
b.EXERGONIC(s)
EXERGONIC
ATP SYNTHESIS FROM ADP AND Pi is a ____ process.
a.EXERGONIC(s)
b.ENDERGONIC(ns)
endergonic
ATP CYCLE?
CONTINUOUS BREAKDOWN AND RESYNTHESIS OF ATP ⚡️
what is a transition state?
IN WHICH BONDS ARE UNSTABLE AND READY TO BE BROKEN
ENZYMES ARE A GROUP OF _________?
Proteins
what do u mean by catalyst?
chemical agent that speed up the rate of reaction without itself being chemically altered.
what would happen to rate of reaction if activation energy is decreased?
enzymes INCREASE the rate of reaction
IS ΔG ALTERED BY PRESENCE OF ENZYME?
NO
ENERGY OF ACTIVATION?
The initial energy investment required to start a chemical reaction.
what provides as the energy barrier preventing molecules from breaking down spontaneously?
energy of activation
the role of enzymes is to _________ the energy of activation?
LOWER
WHAT IS LOCK AND KEY HYPOTHESIS?🔐
EXPLAINS THE SPECIFICITY OF SUBSTRATE-ENZYME INTERACTION
ACTIVE SITE?
SPECIFIC SITE ON AN ENZYME WHERE SUBSTRATE BINDS AND CATALYSIS TAKES PLACE.
WHAT ARE SOME NON-PROTEINS REQUIRED BY ENZYMES?
a.CO-FACTOR- inorganic ions such as iron, copper, zinc
b.COENZYME- organic molecules such as Coenzyme A (CoA), NAD, FAD or ATP
c.PROSTHETIC GROUP-distinctive molecular groups, permanently bound to their enzymes such as HEME OR FLAVIN.
WHAT ARE THE 3 WAYS BY WHICH ENZYME REDUCE THE ACTIVATION ERNGY ?
- Bringing the reacting molecules together
- Exposing the reactant molecule to altered change environment that promote catalysis.
- Changing the shape of substrate molecule.
full form pf ATP?
adenosine 5’-triphosphate
WHAT ARE THE. WAYS THAT ENERGY IS STORED IN LIVING CELL?
- chemical bonds of lipid, starch, or glycogen
- Temporarily stored in ATP for immediate use.
what is the structure of ATP?
NUCLEOTIDE consisting of 3 main parts
a. adenine-‘ N’ contains organic base
b. Ribose- 5-CARBON sugar
c. 3 Phosphate groups
what is the value of ΔG during hydrolysis of ATP AND what does it indicates?
-7.6 Kcal/mol
relatively small amount of energy is required to break the bond
functions of enzymes?
1.lower the activation energy of the specific biochemical reaction.
2.Allowing equilibrium to be approached at fast rate.
name some factors that affect enzyme activity?
1.Change in concentration of substrate and other molecules that bind to enzymes.
2.change in environmental factors, inhibitors, pH, temperature.
with increase in enzyme concentration, rate of of product formation________?
increases
when is an enzyme said to saturated with substrate(SATURATION LEVEL)?
when the catalytic cycle is turning as fast as possible, further increase in substrate concentration has no affect on the reaction rate.
In the presence of excess substrate the rate of catalysis is proportional to _______________.
amount of enzyme
how does ATP donates energy?
Through the transfer of phosphate group
FROM WHERE DOES THE ENERGY TO MAKE ATP comes from?
catabolic reactions that are exergonic
ATP __________ provides energy for cellular processes that are endergonic.
hydrolysis
what is the ph value that most enzymes have?
7
enzymes that are secreted from cells have ph value further from?
neutrality
name the enzyme secreted into the stomach and its ph?
pepsin,1.5
name the enzyme secreted in intestines and its ph?
trypsin, 8
at extreme values of ph what happens to the rate of catalysis?
it drops to zero
how is the rate of reaction affected by change in temp from 0 degree to 40 degree? and above 40 degree?
0º-40º:reaction rate doubles for every 10 degree increase in temp
above 40º:increasing kinetic motions begins to denature the enzyme ,reducing the rate of catalysis.
too much increase in temp affects the rate of reaction in what ways?
👇🏻rapidly zero at about 60º
what are the 2 ways through which ATP is generated?
- Substrate- level phosphorylation:direct formation of ATP by transferring a phosphate group from a high energy compound to a ADP molecule.
- Chemiosmosis- process in cellular respiration and photosynthesis where a proton gradient across a membrane is utilized to generate ATP
what are the two types of chemiosmosis?
OXIDATIVE PHOSPHORYLATION-(cellular respiration)
ATP synthesis driven by electron transfer to oxygen.
PHOTOPHOSPHORYLATION-(photosynthesis)
ATP synthesis driven by light.
how do cells transfer energy?
1.redox reactions
2.electron transfer
in oxidation a cell ______ electrons?
loses
in reduction a cell ______ electrons?
gains
what is more easier-removing electrons from covalent compound or a whole atom?
whole atom
redox reactions usually involves transfer of a ________ atom , rather than just an electron.
hydrogen(containing an electron and proton)
what is an acceptor molecule
a molecule that accepts electrons from other molecule during redox reactions.
name some common acceptor molecules in living cells?
[NAD+ - NADH] - Nicotinamide adenine dinucleotide
[NADP+ - NADPH] - Nicotinamide adenine dinucleotide phosphate [FAD+ - FADH2] - Flavin adenine dinucleotide
[Cytochromes (FeIII) - Cytochromes (FeII)]
[Quinone (Q) - Quinone (QH2)]
how is free energy differentiated in reduced state and oxidized state?
reduces-more free energy
oxidized-less free energy
what are the 2 most important organelles involved in cellular energy conversions?
chloroplast, mitochondia
