BSCI 105 Lecture Notes - Lecture 7: Isomerase, Hydrolase, Allosteric Regulation

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scarletcod663

11 Jul 2016

School

University of Maryland

Department

Biological Sciences Program

Course

BSCI 105

Professor

Keller

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Document Summary

Metabolism the sum of all biochemical reactions in every cell. Reactions occur one after another in an orderly fashion. Capacity to do work: kinetic energy, potential energy stored energy. First law of thermodynamics: conservation of energy , energy can be converted from one form to another, but cannot be created or destroyed. Second law of thermodynamics: entropy in the universe always increases. Energy can be used to increase order in the system. Energy is made available to do work as order decreases in the system. Free energy: measure of the usable energy we get out of breaking a bond in comparison to the amount of energy we lose, energy available to do work, g (gibbs free energy) G gibbs free energy usable energy. H - enthalpy stored total energy in atom or molecule. S unusable or wasted energy entropy. G = g products g reactants. C6h12o6 + 6o2 6co2 + 6h2o: aerobic breakdown of glucose, exothermic, g = -686 kcal/mol.

Related Questions

Question 1 When energy changes from one form to another, some of the energy that can be used to do work is always lost. The loss of this energy is mostly in the form of _________.
a. heat
b. potential energy
c. kinetic energy
d. light energy
e. mechanical energy

Question 2 Which of the following is exergonic?
a. binding fatty acids and glycerol molecules together to form lipids
b. building proteins from amino acids
c. binding sugars molecules together to form glycogen
d. breaking bonds in starch to release glucose
e. adding a phosphate group to ADP to form ATP

Question 3 The first law of thermodynamics states that:
a. energy can neither be created nor destroyed.
b. the universe is increasing in entropy.
c. all living organisms must eat to derive energy.
d. energy is required to bring molecules into a cell against a concentration gradient.
e. in energy-yielding reactions, matter goes from a more-ordered to a less-ordered state.

Question 4 Which of the following is true of energy?
a. It can be transferred from one form to another with 100 percent efficiency.
b. It can be created.
c. It can be stored in chemical bonds.
d. It can never be stored.
e. It can be released by forming chemical bonds.

Question 5 Metabolism is:
a. the sum of all the energy a cell uses.
b. the sum of all the vitamins a cell contains.
c. the sum of all the enzymes a cell contains.
d. the sum of all the chemical reactions that an organism carries out.
e. the sum of all the ATP a cell contains.

Question 6 Entropy is the measure of ________ in a system.
a. disorder
b. order
c. energy
d. work
e. heat

Question 7 What percentage of the energy stored in glucose are humans cells able to use to do useful work?
a. 37%
b. 100%
c. 15%
d. 52%
e. 48%

Question 8 What is activation energy?
a. the energy gained by living things, allowing them to remain active
b. the energy produced by the breakdown of ATP to ADP.
c. the energy required to initiate or begin a chemical reaction
d. the energy created by enzymes during exergonic reactions
e. the energy lost by living things in the form of heat

Question 9 Which of the following is true of allosteric enzymes?
a. Their activity can be reduced when the product binds the enzyme.
b. Their activity can be reduced when a coenzyme binds to them.
c. Their activity can be reduced when the substrate binds the enzyme.
d. Their activity can be increased when the product binds the enzyme.

Question 10 Which of the following is a true statement about enzymes?
a. They are made of proteins.
b. They are altered by the reactions they catalyze.
c. They increase the energy of activation of chemical reactions.
d. All of the above are true.
e. None of the above is true.

Question 11 What is the energy currency of cells?
a. ADP
b. enzymes
c. glucose
d. vitamins
e. ATP

Question 12 Kinetic energy is ____________, while potential energy is _____________.
a. stored energy; energy that is being used
b. stored energy; energy that can't be used
c. energy that is being used; stored energy
d. energy that can't be used; stored energy

Question 13 The energy released during ________ reactions can be used to drive ________ reactions, and this is called ________ reactions.
a. exergonic; endergonic; coupled
b. endergonic; exergonic; coupled
c. exergonic; endergonic; mutually dependent
d. coupled; mutually dependent; independent
e. endergonic; exergonic; mutually dependent

Question 14 ADP + P + Energy --> ATP Which of the following is a true statement about the chemical reaction above?
a. This is a coupled reaction.
b. This is an exergonic reaction.
c. The product of the reaction contains more energy than that of all of the reactants combined.
d. This is an endergonic reaction.
e. This is an example of a catabolic reaction.

greychimpanzee211

The complete set of reactions carried out by an organism is called:

a. anabolism

b. catabolism

c. metabolism

Value: 2

The breakdown of starch is broken down to glucose is an example of:

a. anabolism

b. catabolism

c. metabolism

Value: 3

For the following statement, determine which description best describes the process: DNA is synthesized from free nucleotides.

a. anabolism

b. catabolism

c. metabolism

Value: 4

Fill in the blank: Catabolic reactions result in the synthesis of molecules of .............via cellular respiration. This is then used to power anabolic reactions.

Value: 5

The energy in organic molecules is released in a series of steps because:

a. it is not possible to release it in a single step.

b. more total energy is released in multiple steps than would be released in a single step

c. less total energy is released in multiple steps than would be released in a single step.

d. more energy can be harvested for cellular use in multiple steps than from a single step.

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photosynthesis

1-The light reaction of photosynthesis does not include

a. chemiosmosis

b. oxygen liberation

c. glucose synthesis

d. electron transport

Value: 2

Photosynthesis takes place in the membranes of small sacs called

a. thylakoids

b. photosystems

c. stroma

d. photons

Value: 3

During what stage of photosynthesis is O2 produced?

a. the light-dependent reactions involving photosystems I and II

b. carbon fixation

c. the Krebs cycle

d. O2 is not produced during photosynthesis

Value: 4

The pigment molecules responsible for photosynthesis are located in the

a. mitochondria

b. cytoplasm of the cell

c. stroma of the chloroplast

d. thylakoid membrane of the chloroplast

Value: 5

During what stage of photosynthesis are ATP and NADPH converted to ADP + Pi and NADP+?

a. the light-dependent reactions

b. the light-independent reactions

c. both of the above

d. none of the above

Value: 6

What energy-rich organic compound is produced as a result of the Calvin cycle?

a. ATP

b. NADPH

c. glucose

d. H2O

Value: 7

During photosynthesis, photons raise electrons to higher energy levels. These excited electrons belong to what compound?

a. water

b. ATP

c. chlorophyll

d. electron transport chain

Value: 8

Which of the following statements accurately describes the relationship between photosynthesis and cellular respiration?

a. photosynthesis occurs only in autotrophs; cellular respiration occurs only in heterotrophs

b. photosynthesis uses solar energy to convert inorganics to energy-rich organics; respiration breaks down energy-rich organics to synthesize ATP

c. photosynthesis involves the oxidation of glucose; respiration involves the reduction of CO2

d. the primary function of photosynthesis is to use solar energy to synthesize ATP; the primary function of cellular respiration is to break down ATP and release energy

3) The hydrolysis of sucrose to glucose and fructose is exergonic. However, if you dissolve sucrose in water and keep the solution overnight at room temperature, there is no detectable conversion to glucose and fructose. Why?

Select one:

a. The change in free energy of the reaction is negative.

b. The activation energy of the reaction is high.

c. The free energy of the products is higher than the free energy of the reactants.

d. This is a condensation reaction.

e. The change in free energy of the reaction is positive.

5) Competitive inhibition differs from non-competitive inhibition in that the ___1___ site is where we see competitive inhibition, while the non-competitive inhibitor __2___.

1. a. allosteric b. non-active c. active d. hydrophillic e. hydrophobic

2.
a. binds to the active site, thus blocking it
b. binds outside the active site, changing the shape of the enzyme
c. binds outside the active site, and blocks the active site

6) Phosphofructokinase is an enzyme, and as such it __1___ of the reaction. It is part of glycolysis, and is an example of an enzyme controlled by inhibition, as high levels of citrate (an intermediate further down the catabolic pathway) turns the enzyme off
(1)Select one:
a. lowers activation energy
b. lowers the ÎG
c. raises the Free Energy
(2)Select one
a. non-competitivenegative feedback
b. irreversible competitivereversible competitive.

15)The reactions in the pathways of glycolysis and the citric acid cycle harvest the high-energy electrons stored in glucose. Therefore, these pathways _______________.

Select one:

a. take place in animal cells, but not in plant cells
b. are catabolic pathways
c. are anabolic pathways
d. involve the reduction of glucose and its metabolic intermediates

21) In an exergonic chemical reaction, the products have less free energy than the reactants (-ÎG). Endergonic reactions require an input of energy (+ÎG). The addition of starting materials and the removal of end products prevent metabolism from reaching final equilibrium. Instead, the cell exists in a state of dynamic equilibrium.

Select one:
True
False

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BSCI 105 Lecture Notes - Lecture 7: Isomerase, Hydrolase, Allosteric Regulation

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