Biology- 1406 Exam 2
Which of these is NOT a product of the citric acid cycle?
acetyl CoA
Which term describes the degree to which an element attracts electrons?
electronegativity
How would anaerobic conditions (when no O2 is present) affect the rate of electron transport and ATP production during oxidative phosphorylation? (Note that you should not consider the effect on ATP synthesis in glycolysis or the citric acid cycle.)
both electron transport and ATP synthesis would stop
when the noncompetitive inhibitor is bonded to the enzyme, the shape of the ___ is distorted
enzyme
TRUE OR FALSE: In the light reaction of photosynthesis, the light energy from the sun is converted to chemical energy in glucose
false
What type of reaction breaks the bonds that join the phosphate groups in an ATP molecule?
hydrolysis
An enzyme ___.
is an organic catalyst
As a result of its involvement in a reaction, an enzyme _____.
is uncharged
what ultimately happens to the oxygen that we inhale?
it combines with electrons & hydrogen ions to form water
In muscle cells, fermentation produces _____.
lactate and NAD+
Enzyme X has an optimum pH of 3 & optimum temperature of 40 degrees celsius a solution with enzyme X is at neutral pH at 40 degree celsius. The activity of the enzyme will increase by ____.
making the pH more acidic
an inhibitor binds to a site on the enzyme that is not the active site
noncompetitive inhibitor
When a compound donates (loses) electrons, that compound becomes _______. Such a compound is often referred to as an electron donor.
oxidized
in general, enzymes are what kind of molecules?
proteins
Once the electron donor in glycolysis gives up its electrons, it is oxidized to a compound called
pyruvate
In fermentation _____ is reduced and ____ is oxidized?
pyruvate ... NADH
Among the products of glycolysis, which compounds contain energy that can be used by other biological reactions?
pyruvate, ATP, and NADH
When a compound accepts (gains) electrons, that compound becomes ______. Such a compound is often referred to as an electron acceptor.
reduced
Enzymes work by _____.
reducing EA (energy of activation)
Which of the following generates the most ATP? A.) Fermentation of 10 molecules of glucose to latic acid B.) Breakdown of 1 glucose molecule to 6CO and 6H2O C.) Oxidation of 15 glucose molecules to pyruvric acids
B
Which of the following statements is true regarding the Kreb's cycle? A.) Takes place in cristae B.) Oxidizes acetyl- CoA to CO2 C.) it produces 2 ATP, and uses 2 ATP
B
Which of the following is true of enzymes?
Enzymes increase the rate of chemical reaction by lowering activation energy barriers.
____ is the compound that functions as the electron acceptor in glycolysis
NAD+
The reduced form of the electron acceptor in glycolysis is ______.
NADH
Which of the following statements is true of the bonds in a water molecule?
Oxygen holds electrons more tightly than hydrogen does, and the net charge is zero
TRUE OR FALSE: An enzyme is required in order for the reaction to occur
TRUE!
TRUE or FALSE: a bond must be broken between an organic molecule and phosphate before ATP can form
TRUE!
TRUE or FALSE: one of the substrates is a molecule derived from the breakdown of glucose
TRUE!
What is the similarity of passive and active transport?
They both use transport protein
In mitochondrial electron transport, what is the direct role of O2?
To function as the final electron acceptor in the electron transport chain
TRUE OR FALSE: Reducing agents donate electrons & are oxidized
True!
TRUE OR FALSE: Whenever energy is transformed, there is always an increase in the entropy of the universe
True!
Which term describes two atoms when they form a bond in which electrons are completely transferred from one atom to the other?
anion and cation
In your body, what process converts the chemical energy found in glucose into the chemical energy found in ATP?
cellular respiration
An inhibitor that has a structure that is so similar to the substrate that it can bond to the enzyme just like the substrate
competitive
Increasing the substrate concentration in an enzymatic reaction could overcome which of the following?
competitive inhibition
The organism that use light as source of energy and carbohydrates as source of carbon are called _____?
photohetertrophs
Chemical energy is a form of ____ energy.
potential
Increasing enzyme concentration in an enzymatic reaction could overcome which of the following?
saturation of the enzyme activity
What name is given to the reactants in an enzymatically catalyzed reaction?
substrate
enzyme inhibitors disrupt normal interaction between an enzyme and its ____.
substrate
In glycolysis, ATP molecules are produces by ___.
substrate-level phosphorylation
In the citric acid cycle, ATP molecules are produces by ___.
substrate-level phosphorylation
Energy is observed in two basic forms: potential and kinetic. Which of the following correctly matches these forms with a source of energy?
the covalent bonds of a sugar molecule: potential energy
Which of the following statements about the combustion of glucose with oxygen to form water and carbon dioxide (C6H12O6+6O2=>6CO2+6H2O) is correct?
the entropy of the products is greater than the entropy of the reactants
Which of the following statements about feedback regulation of a metabolic pathway is correct?
the final product of a metabolic pathway is usually the compound that regulates the pathway
For living organisms, which of the following is an important consequence of the first law of thermodynamics?
the organism ultimately must obtain all the necessary energy for life from its environment
TRUE OR FALSE: when there is higher concentration of ATP, the activity of PFK is lower?
true!
How many NADH are produces by glycolysis?
2
In glycolysis there is a net fain of ____ ATP
2
Describe an ATP molecule
3 phosphates, a ribose, and adenine
how many ATPs would be generated from aerobic cellular respiration of 2 molecules of glucose in bacteria
76
Which of the following statements is false regarding glycolysis? A.) Glycolysis requires O2 B.) Gylcolysis takes place inside the cell C.) Gylcolysis produces a net of 2ATP, 2NADH, & 2 pyruvate.
A
in glycolysis, what starts the process of glucose oxidation?
ATP
Which of these enters the citric acid cycle?
Acetyl CoA
Which of these is NOT a product of glycolysis?
FADH2
Which of the following metabolic processes can occur without a net influx of energy from some other process?
C6H12O6+6O2=>6CO2+6H2O
After the citric acid cycle, the carbon in the acetyl -CoA us released as ____.
Carbon Dioxide
TRUE OR FALSE: The phosphate group added to ADP to make ATP comes from free inorganic phosphate ions
FALSE
TRUE OR FALSE: the enzyme involved in ATP synthesis must be attached to a membrane to produce ATP
FALSE
TRUE OR FALSE: The chlorophyll is located in the thylakoid in the mesophyll cell in the chloroplast in the leaf
False
TRUE OR FALSE: Glycolysis in eukaryotes involves 10 steps breaking glucose to 6CO2 and 6H2O with a net gain of 2 ATP in stage 1.
False!
TRUE OR FALSE: In feedback inhibition of enzyme regulation, the final or end product of a metabolic pathway, binds to the initial reactant of the pathway.
False. it binds to the enzyme
TRUE OR FALSE: The energy that is released as the electrons move down the ETS us used to pump electrons from matrix to intermembrane space of the mitochondria.
False; it pumps protons, not electrons
why more ATP is made per molecule of NADH than per molecule of FADH2?
Fewer protons are pumped across the inner mitocondriamembrane
Which of the following statements is NOT true of most cellular redox reactions?
a hydrogen atom is transferred to the atom that loses an electron
the competitive inhibitor competes with the substrate for the ____ on the enzyme
active site
"conservation of energy" refers to the fact that ___.
energy cannot be created or destroyed but can be converted from one form to another
In glycolysis, the carbon-containing compound that functions as the electron donor is _______.
glucose
Which of these are by-products of cellular respiration?
heat, carbon dioxide, and water
Gaseous hydrogen burns in the presence of oxygen to form water: 2H2 + O2 → 2H2 O + energy Which molecule is oxidized and what kind of bond is formed?
hydrogen, polar
What kind of bond is formed when lithium and fluorine combine to form lithium fluoride?
ionic
an inhibitor that usually forms a covalent bond with an amino acid side group within the active site, which prevents the substrate from entering the active site or prevents catalytic activity.
irreversible
The sodium-potassium pump _____.
move na+ outside the cell and k+ inside the cell against their concentration gradients
