ch. 5 part a
Only part of the energy released in catabolism is actually available for cellular functions bc....
of the energy is lost to the environment as heat
what is exergonic
produce more energy than they consume
what is catalysts
substances that can be speed up a chemical reaction without being permanently altered themselves
what is example of substrate
sucrose(table sugar) is the substrate fo the enzyme sucrase, which catalyzes the hydrolysis of sucrose to glucose and fructose
what is catabolism
the breakdown of complex organic compounds into simpler ones
can metabolism be divided into 2 classes of chemical reactions
true
does each chemical reaction requires a specific level of energy
true
what does dehydration synthesis reactions release
water
What is an example of catabolism?
when cells break down sugars into carbon dioxide and H20.
cell's metabolic pathways are determined by its enzymes
which are in turn determined by the cell's genetic makeup
for reactions to take place
atoms, ions, or molecules must collide
what are the building blocks for anabolic reactions and furnish the energy needed to drive anabolic reactions
catabolic reactions
what energy is required for a chemical reaction
collision energy
what is enzyme-substrate complex
formed by the temporary binding of enzyme and reactants enables the collisions to be more effective and lowers the activation energy of the reaction
what are enzymes
in living cells serve as biological catalysts
what is the function of enzymes
is to speed up biochemical reactions at a temperature that is compatible with the normal functioning of the cell
enzymes are
large globular proteins in molecular weight form about 10000 to several million
what does biosynthetic reactions generate
materials for cell growth
higher the particles' velocities
more probable that their collision will cause a reaction
if colliding particles posses the mininum energy needed for reaction
no reaction will take place unless the particles are properly oriented toward each other
what are the 2 classes of chemical reactions can metabolism be divided
1) those that release energy 2) those that require energy
what is link between children getting cavities in the middle of the summer?
Dental caries are caused by oral streptococci, including S. mutans, S. salivarius, and S. sobrinus, that attach to tooth surfaces. Oral streptococci ferment sucrose and produce lactic acid, which lowers the salivary ph.
enzyme orients the substrate into
a position that increases the probability of a reaction
what is active site
a region that interacts with a specific chemical substance
what are examples of anabolism?
1)formation of proteins from amino acids 2)nucleic acids from nucleotides 3)polysaccharides from simple sugars
energy-requiring and energy-releasing reactions is made possible thru what molecule
adenosine triphosphate(atp)
the energy from catabolic reactions used to combine adp and a p(i) to resynthesize atp:
adp + p(i) + energy > ATP
what is basis of collision theory is that
all atoms, ions, and molecules are continuously moving and are thus continuously colliding with one another
anabolic reactions are coupled to ATP breakdown, and catabolic reactions are coupled to what synthesis
atp
why can metabolism be viewed as energy-balancing act
because chemical reactions either release or require energy
what is the solution to dental caries?
bubblegum switched with a sugarless gum made with xylitol, a naturally occuring sugar alcohol, can significantly lower the number of dental caries in children bc it lowers the number of S. mutans in the mouth
what is anabolism?
building of complex organic molecules into simpler ones
why does temperature increase the reaction rate of a substance
by causing the molecules to move faster, heat increases both the frequency of collisions and the number of molecules that attain activation energy
What are hydrolytic reactions?
catabolic reactions which use water and which chemical bonds are broken
Atp stores energy derived from catabolic reactions and releases it later to drive what reaction and perform other cellular work
anabolic reactions
Enzyme-regulated energy requiring reactions are mostly
anabolism
what is endergonic
consume more energy than they produce
what is substrate
each acts on a specific substance when there are two or more reactants
What are anabolic processes
endergonic
when the terminal phosphate group is split from atp, adenosine diphospate(adp) is formed
energy is released to drive anabolic reactions
principal properties of a group of proteins involved in almost all biologically important chemical reactions
enzymes
as catalysts
enzymes are specific
what is a catabolic or degradative reaction?
enzymes needed to metabolize a nutrient are produced only when needed
as catalysts,
enzymes typically acclerate chemical reactions
what is collision theory
explains how chemical reactions occur and how certain factors affect the rates of those reactions
because cell must use energy to maintain life, new what
external sources of energy
chemical reactions occur when chemical bonds
formed or broken
what is reaction rate
frequency of collisions containing sufficient energy to bring about a reaction-depends on the number of reactant molecules at or above the activation energy level
what is activation energy
which is the amount of energy to disrupt the stable electronic configuration of any specific molecule so that the electrons can be rearranged
When pressure is increased or when the reactants are more concentrated because the distance between molecules is thereby decreased
number of collisions also increases
what is metabolism
refers to the sum of all chemical reactions within a living organism
each known enzymes has a characteristic 3 dimensinal shape with a specific surface configuration
result of its primary, secondary, tertiary structures
what is metabolic pathways
sequences of chemical reactions
why is it important for the enzyme's ability to accerlate a reaction without the need for an increase in temperature to living systems
significant temperature increase would destory cellular proteins
what does the enzyme do to the reaction by increasing the number of AB molecules that attain sufficient activation energy to react
speeds up
population of molecules of substance AB, at specific temperature, some molecules possess relatively little energy;
the majority of the population possesses relatively little energy; and a small portion of the population has high energy
what are anabolic or biosynthetic reaction
the production of complex molecules within living organisms or cells
what enables each enzyme to find the correct substrate from among the large number of divers molecules in the cell
the unique configuration
several factors determine whether a collision will cause a chemical reaction:
the velocities of the colliding particles, their energy, and their specific chemical configurations
the energy transferred by the particles in the collision can disrupt
their electron structures enough to break chemical bonds or form new bonds
what is the specifity of enzymes is made possible by what
their structure
for example, if only the high-energy AB molecules are able to react and converted to A and B molecules,
then only relatively few molecules at any one time possess enough energy to react in a collision
molecules of substance AB(the reactant) are converted
to molecules of substances A and B (the products)
what is one way to increase the reaction rate of a substance
to raise its temperature
Catabolism involved in the enzyme-related chemical reactions that release energy in living cells
true
Does anabolic processes involve dehydration synthesis
true
In living systems, enzymes increase the reaction rate without raising the temperature
true