Download Samples Ch 10 to 12.tst

Sample Exam Questions Ch 10 to 12
Name___________________________________
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
1) An enzyme will increase the rate of certain reactions with certain substances. This characteristic is
called:
A) inhibition
B) specificity
C) regulation
D) selectivity
1)
2) The optimum pH for an enzyme such as hexokinase that phosphorylates glucose in the blood
would be:
A) 2.0
B) 9.0
C) 7.5
D) none of these
2)
3) What factors can influence the speed of a reaction by an enzyme?
A) The orientation of the reactants
B) The closeness of the reactants to each other in the active site
C) The weakening of bond energies in the reactants
D) All of the above
3)
4) Penicillin is an example of a(n):
A) reversible inhibitor
C) noncompetitive inhibitor
4)
B) irreversible inhibitor
D) activator
5) The point at which an enzyme reacts at its maximum activity is called a:
A) reaction maximum
B) saturation point
C) pH dependence
D) steady state
5)
6) A fast reaction rate for a chemical reaction is dependent on:
A) having a small activation energy
B) having a large activation energy
C) being endothermic
D) being exothermic
6)
7) What is the primary function of enzymes?
A) Biochemical catalysts
C) Structure
7)
B) Neurotransmitters
D) Transport
8) The area on the enzyme that interacts with the substrate is called the:
A) allosteric site
B) regulatory site
C) active site
8)
D) modulator site
9) The phosphodiester bond that forms between two adjacent sugars is connected via which two
carbons of the sugar molecules?
A) 2' and 6'
B) 3' and 5'
C) 1' and 6'
D) 1' and 5'
10) The type of RNA that contains the anticodon for an amino acid is called:
A) tRNA
B) vRNA
C) rRNA
D) mRNA
11) What is complimentary strand for a DNA sequence, TCGA?
A) CTAC
B) GATC
C) TGCA
D) AGCT
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9)
10)
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12) Thymine is what type of nitrogenous base?
A) Porphyrin
B) Pyrrole
12)
C) Purine
13) The second step of protein synthesis occurs in the ribosomes and is called:
A) translation
B) transfer
C) transcription
D) Pyrimidine
13)
D) copying
14) Which reaction in the citric acid cycle loses CO2 ?
14)
A) Conversion of malate to oxaloacetate
B) Conversion of isocitrate to α-ketoglutarate
C) Conversion of fumarate to malate
D) Conversion of succinate to fumarate
15) The acetyl group in acetyl CoA is linked through what kind of bond?
A) C-O bond
B) C-C bond
C) C-N bond
15)
D) C-S bond
16) In the conversion of pyruvate to acetyl CoA what molecule along with CO2 is formed?
A) NADH
B) ADP
C) ATP
16)
D) NAD+
17) Molecular collisions in a reaction are necessary for a reaction to take place because:
A) the collisions of rapidly moving molecules provide energy
B) the reactant molecules must directly interact with each other to produce product
C) the number of collisions
D) all of the above
17)
18) Some enzymes require certain metal ions, such as Mg+2 or Zn+2 , in order to have full activity. This
component is called a:
A) cofactor
B) substrate
C) regulator
D) coenzyme
18)
19) The protein factory in a cell is contained in a ribosome. The ribosome is made of what type of
nucleic acid strands?
A) mRNA
B) vRNA
C) tRNA
D) rRNA
19)
20) The beginning process of protein synthesis by DNA is called:
A) transfer
B) translation
C) transcription
20)
D) copying
21) How many CO2 molecules are formed in one turn of the citric acid cycle?
A) 2
B) 1
C) 4
21)
D) 6
22) When a molecule binds to an enzyme at a site other than the active site and affects enzyme shape
it is called a(n):
A) irreversible inhibitor
B) competitive inhibitor
C) covalent modification
D) noncompetitive inhibitor
22)
23) A correct set of complimentary base pairs in DNA are:
A) AT
B) TC
C) AU
23)
D) GA
24) Which of the following is the first molecule formed in the citric acid cycle?
A) Citrate
B) Fumarate
C) Oxaloacetate
D) Succinate
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24)
SHORT ANSWER. Write the word or phrase that best completes each statement or answers the question.
25) Give several types of substances that could cause a mutation.
25)
26) How many ATP are formed from one palmitic (C16) acid molecule undergoing beta
oxidation?
26)
27) What are two components that common to all viruses?
27)
28) Explain the process of ketosis.
28)
29) Define what is meant by a retrovirus.
29)
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Answer Key
Testname: SAMPLES CH 10 TO 12
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B
C
D
B
D
A
A
C
B
A
D
D
A
B
D
A
D
A
D
C
A
D
A
A
Replication errors, environmental agents, radiation, carcinogens
There will be 7 turns of the beta oxidation and formation of 8 acetyl CoA molecules: therefore the 8 acetyl CoA will
yield 80 ATP, and then 17.5 ATP from the NADH of the cycle and 10.5 ATP from the FADH2 . The final total would
be 108 ATP.
27) nucleic acids-either RNA or DNA, capsids
28) Ketosis occurs when there is an excessive amount of ketone bodies; this generally happens when a diabetic doesn't
have enough glucose to get into the cells.
29) It is a retroviral RNA that makes viral DNA by a process called reverse transcription.
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