Bio 160 Ch 5
An increase in entropy means a _____in available energy.
Decrease
The first law of thermodynamics states that energy can not be created nor ___, only change from one form to another. The total amount of energy in the universe remains _____.
Destroyed, constant
What equation correctly represents the mechanism of enzyme function?
E+S-> E-S-> E-P-> E+P
A reaction in which the product contain more energy than the reactants is called an ______ reaction.
Endergonic
Every reaction takes a certain amount of _____ to begin.
Energy
All activities of living organisms involve changes in ____ energy. Two laws of ____ govern changes of energy in the universe.
Energy, thermodynamics
What might happen if a substance that is not a substrate molecule binds to an enzymes activation site?
Enzyme activity will slow down
A reaction in which the products contain less energy than the reactants is called an _____ reaction.
Exergonic
TRUE OR FALSE: all biochemical pathways have the same number of enzymatic reactions
False
TRUE OR FALSE: an enzyme can only bind one reactant at a time
False
TRUE OR FALSE: an enzyme speeds up a chemical reaction in the cell, but can only be used once
False
TRUE OR FALSE: if the end product of a biochemical pathway becomes available in the environment, it is crucial for the cell to continue making the product.
False
Blood sugar refers to what molecule circulating in blood?
Glucose
All forms of energy can converted into ___.
Heat
This energy is lost as ____.
Heat
A change in pH can affect such things as interactions and ionization, or it can even make the enzyme
Inactive
All cells go through transformations, they ____ the total entropy of the universe.
Increase
The binding of a signal molecule called an ____ alters the shape of the active site such that it can bind to the substrate
Activator
In competitive inhibition, a signal molecule interferes with the _____site of an enzyme.
Active
Enzymes that have shapes that can be altered by the binding of signal molecules are called ____ enzymes.
Allosteric
Consider the biochemical pathway. A-E1->B-E2->C. If enzyme 2 is inactive, which of the following compounds will accumulate?
B only
What statement about biochemical pathways is true?
Biochemical pathways can can convert an initial substrate via a series of steps into an end product.
A chemical reaction is the making or breaking of chemical ____.
Bonsa
How does sucrose change the configuration of sucrase?
By binding to the active site
All chemical activities can be viewed as a series of ________ between molecule.
Chemical reactions
Through ____ reactions, the potential energy within molecules can be converted into kinetic energy that organisms can use to do work.
Chemical
Entropy is the term used to indicate the relative amount of _____.
Disorder
Protein or nucleus acid molecules that function as catalysts are called
Enzymes
How many times can a sucrase molecule be used to hydrolysis sucrose?
Many
Inactivity of an enzyme as a result of pH occurs because of changes in the enzyme shape.
Conformational
Fire wood, beans as a meal, flames of a burning fire, hiking, moving water in a stream. Which are potential or kinetic energy?
Kinetic energy: flames of a burning fire, hiking, moving water in a stream. Potential energy: fire wood, beans as a meal
Energy comes in two forms: ____ and potential energy. Kinetic energy is the energy of _____, whereas potential energy is stored energy.
Kinetic, motion
Energy transformation makes the universe ____ ordered.
Less
Enzymes speed up chemical reactions by
Lowering the energy of activation required
Where is sucrose found in the human body?
On the microvilli of the small intestine
The second law of thermodynamics states that without an input of energy, energy transformations proceed from a more _____, less stable form to a more _____, stable form.
Ordered, disordered
Many enzymes working in a series of linked reactions to create an end product is a buochemical
Pathway
In chemical reactions, the ____ energy contained in chemical bonds is transferred between molecules or used to do work.
Potential
Plants, algae and some kinds of bacteria can capture this solar energy and use it to build molecules, which contain ____ energy in the bonds between atoms.
Potential
In chemical reactions, reactants are substances that participate in a reaction, while _____ are substances that form as a result of a reaction.
Products
The molecules that result after a reaction has taken place are called ______.
Products
Enzymes can be made of
Proteins
In a chemical reaction, the original molecules are called the ____, or substrates
Reactants
The binding of a signal molecule called a ____ alters the shape of the active site such that it cannot bind the substrate.
Repressor
This is referred to as the ___ law of thermodynamics.
Second
What is the ultimate source of energy in the biosphere?
Solar energy from the sun
For example, when plant cells photosynthesize, they use ______ to form carbohydrate molecules from carbon dioxide. Not all of the captured solar energy is used to make carbohydrates; some becomes _____.
Solar energy, heat
The energy of activation is best described as ____.
The energy threshold that must be reached before a reaction can proceed and products may be formed.
What is thermodynamics?
The study of energy or "heat changes"
TRUE OR FALSE: a biochemical pathway consists of a specific sequence of enzyme-catalyzed reactions
True
TRUE OR FALSE: enzymes are catalysts that sped up chemical reactions
True
TRUE OR FALSE: enzymes have no effects on the energy levels of the reactants or products of reactions, only the energy of the activation.
True
TRUE OR FALSE: in a biochemical pathway, the product of the first reaction becomes the substrate in the second reaction.
True
Energy is the ability to do____. To maintain their organization and carry out metabolism, organisms need a constant supply of ____.
Work, energy
Consider the biochemical pathway used to synthesize the amino acid proline. A large increase in the level of proline will most likely lead to
a decrease in proline production.
A substrate can bind to the _____ of an enzyme, and the subsequent reaction produces an end product.
active site
Enzymes have various factors that can affect their ____. Some of these factors include concentration, temperature, and ___.
activity, pH
What does the inhibitor bind to during feedback inhibition?
allosteric site of the enzyme being inhibited
In simple terms sucrase
breaks sucrose into glucose and fructose
Feedback inhibition occurs when a plentiful _____ binds to an enzymes active site, which prohibits substrate binding and inactivates the metabolic pathway.
end product
In most cases, the activity of an enzyme is regulated by
feedback inhibition
Consider the biochemical pathway. A-E1->B-E2->C. Enzyme 1 can utilize?
only A as substrate.
Energy flows into the biological world from the ____.
sun
In feedback inhibition, the inhibitor of the biochemical pathway is typically
the final product of the biochemical pathway.
