Exam 1 Questions

Question 1

translation is the process by which:
A. RNA is synthesized from DNA
B. DNA is synthesized from protein
C. proteins are synthesized from DNA molecules
D. RNA is synthesized from protein
E. proteins are synthesized from RNA molecules

Answer 1

E

Question 2

the cell is the fundamental unit of life. all cells:
A. have a plasma membrane
b. harness energy from the environment
c. store DNA in their nucleus
D. all of the above
E. A and B are true

Answer 2

E

Question 3

The ability of an atom to react and for bonds with another atom is determined directly by:
A. the atomic number of the atom
B. the number and distribution of the valence electrons
C. the row of the periodic table in which the element is found
D. the number of electrons in the first shell surrounding the nucleus
E. the number of neutrons in relation to the number of electrons

Answer 3

B

Question 4

Prokaryotic cells and eukaryotic cells differ in that:
A. prokaryotic cells have a nucleus and eukaryotic cells do not
B. eukaryotic cells have a spliceosome, prokaryotic cells do not
C. prokaryotic cells can produce monocistronic transcripts, transcripts in eukaryotes are polycistronic
D. eukaryotes use RNA Pol II for transcription, prokaryotes use ribosomes
E. all of the above

Answer 4

B

Question 5

the central dogma of molecular biology states that information flows from DNA to RNA to protein. which of the following molecules contradicts the central dogma?
A. primary RNA transcripts
B. rRNA
C. mRNA
D. all of these 
E. none of these

Answer 5

B

Question 6

Which of the following molecules is not held together by ionic bonds?
A. LIF
B. KCL 
C. NaI
D. MgCl2
E. all of these

Answer 6

E

Question 7

which of the following ranks the elements carbon, sodium, calcium, and iodine in order of increasing number of valance electrons?
A. C

Answer 7

E

Question 8

several chemical properties make water uniquely suited for its role as a central molecule of life. which of the following is true?
A. Hydrogen bonds form between adjacent water molecules
B. water is a poor solvent of molecules with ionic bonds such as NaCl
C. water molecules are almost always polar
D. The structure fo a water molecule is destabilized by hydrogen bonds
E. the oxygen in water has a slight positive charge

Answer 8

A

Question 9

Biological polymers are:
A. strings of repeated units (called monomers) linked together by hydrogen bonds
B. assembled from monomer units that are exactly identical to one another
C. molecules that spontaneously form in cells without an input of energy
D. strings of monomers linked by covalent bonds
E. none of the above

Answer 9

D

Question 10

Imagine that you are an interior architecture/biology double major. while at home during break, one of your friends asks you to design and help build a spiral staircase that is modeled after a DNA molecule. the stair case must have 14 steps and each step needs to be 9 feet wide. you say okay as long as you provide the materials. so your friend asks you for a list of materials needed to build the staircase which of the following include the items necessary to make a staircase that accurately reflects how bases and the backbone form the molecular structure of a DNA molecule?
A. 2 railings and 14 board (each of which are 9 feet wide)
B. 2 railings and 28 boards (12 that are 3 feet long and 12 that are 6 feet long)
C. 1 railing and 14 boards (each of which is 9 feet wide)
D. 1 railing and 28 boards (12 that are 3 feet long and 12 that are 6 feet long)
E. 2 railings and 28 boards (each of which is 4.5 feet long)

Answer 10

B

Question 11

In the DNA sequence 5’-TGAC-3” the phosphodiester linkage between the thymine and the guanine connects:
A. the 3’ end of the guanine to the 5’ end of the thymine
B. the 3’ end of the thymine to the 5’ end of the guanine
C. the 2’ end of the thymine to the 3’ end of the guanine
D. the 5’ end of the thymine to the 3’ end of the guanine
E. the 3’ end of the guanine to the 3’ end of the thymine

Answer 11

B

Question 12

Non-virulent bacterial can be prevented from being transformed into virulent bacteria if the debris from the heat-killed virulent bacteria is first treated with: 
A. RNase
B. protease
C. DNase
D. polymerase
E. A and C

Answer 12

C

Question 13

which of the following most accurately describes a polar covalent bond?
A. the interaction of a hydrogen connected to an atom with a high electronegativity, and an electronegative atom of another molecule
B. the interaction of an atom with very high electronegativity and an atom with very low electronegativity
C. the equal sharing of electrons between an atom with a partial positive charge and an atom with a partial negative charge
D. the unequal sharing of electrons between atoms with different electronegativities
E. none of these

Answer 13

D

Question 14

During elongation of translation, the growing polypeptide is transferred from the tRNA in the \_\_ site of the ribosome to the tRNA in the \_\_\_ site as a peptide bond is formed between the growing polypeptide and the newest tRNA. 
A. A; P
B. A;E
C. P; A
D. P ; E
E. E ; A

Answer 14

C

Question 15

which of the following types of post-transcriptional modifications is( are) common in prokaryotes?
A. polyadenlyation
B. intron removal
C. 5’ cap addition
D. all of these
E. none of these choice are correct, prokaryotes don’t process transcripts

Answer 15

E

Question 16

in transcription the energy to attach each successive ribonucleotide to the growing RNA chain comes from:
A. energy stored in RNA polymerase
B. cleavage of the high energy phosphate bonds of the growing transcript
C. cleavage of the high energy phosphate bonds of the incoming nucleoside triphosphate
D. Cleavage of the 2’ hydroxyl group of the ribose of the incoming nucleotide
E. all the above

Answer 16

C

Question 17

given what you know about the number of electrons in the outer shell of carbon, what is the most likely structural formula for carbon dioxide?
A. O-C-O
B. O=C=C
C. O=C-O
D. O-C=O

Answer 17

B

Question 18

an intron is:
A. a protein that is removed following translation
B. found only in eukaryotes
C. a transfer RNA that binds to the codon
D. part of an intact, mature mRNA that leaves the nucleus
E. a series of amino acids at the end of anew polypeptide that directs transcription

Answer 18

B

Question 19

if you isolate a single nucleotide from a nucleic acid chain and determine that the nitrogenous ring structure is cytosine, you could say with certainty that the nucleotide could have come from: 
A. DNA but not RNA
B. RNA but not DNA
C. either DNA or RNA
D. a prokaryote but not a eukaryote
E. a eukaryote but not a prokaryote

Answer 19

C

Question 20

which one of the following amino acids when incorporated into growing polypeptide stand, adds flexibility to the molecule?
A. glycine
B. serine
C. cysteine
D. glutamic acid
E. proline

Answer 20

A

Question 21

which one of the following is not a component of a nucleosome core particle?
A. histone H4
B. approximately 150 base pairs of DNA
C. histone H2A
D. histone H3
E. all are part of the nucleosome

Answer 21

E

Question 22

which of the following protein structure results exclusively from hydrogen bonding?
A. secondary structures
B. alpha helix
C. beta sheet
D. B and C
E. A B and C

Answer 22

E

Question 23

what are the cellular components responsible for the following list of processes during either transcription or translation?
1. processes primary transcripts by joining eons
2. binds to enhancer regions
3. adds amino acids by generating peptide bonds via a condensation reaction
4. converts tRNAs from uncharged to charged
A. spliceosome, transcription factor, RNA polymerase, ribosome
B. RNA polymerase, transcriptional activator, tRNA, aminoacyl synthetase
C. RNA polymerase, transcription enhancer, ribosome, spliceosome
D. spliceosome, transcriptional activator, ribosome, aminoacyl synthetase
E. spliceosome, transcriptional factor, ribosome, RNA polymerase

Answer 23

D

Question 24

you are translating an mRNA in the lab and notice that the protein produced is only two amino acids long. you were expecting a length of forty amino acids you check the sequence of the mRNA and everything appears correct. What could be happening in your reaction?
A. the DNA from which the mRNA was transcribed has a mutation
B. the acceptor (A) site of the ribosome is not functioning
C. the exit (E) site of the ribosome is not functioning
D. peptide bonds are not forming properly
E. all of these options could produce the result you observe

Answer 24

C

Question 25

which one of the following steps in translation is not a part of the initiation phase?
A. recognition of the 5’ cap by initiation factors
B. identification of an ATG codon by a tRNA charged with Met
C. recruitment of the large ribosomal subunit
D. loading of the met charged tRNA into the P site
E. all of the above

Answer 25

B

Question 26

a polycistronic mRNA with six protein coding genes has: 
A. 6 start codons and 6 stop codons
B. 1 start codon and 6 stop codons
C. 6 start codons and 1 stop codon
D. 1 start codon and 1 stop codon
E. 3 Start codons and 3 stop codons

Answer 26

A

Question 27

predict the consequences on protein synthesis in a eukaryotic cell in which the complex responsible for adding the poly A tail functions inefficiently such that the poly A tail of mRNAs are half the length that they should be:
A. tRNAs would no longer be able to recognize the mRNA
B. ribosomes in the nucleus would degrade the mRNAs so no translation would occur
C. mRNAs would be degraded more rapidly resulting in fewer proteins
D. all of the above
E. there would be no effect on protein synthesis

Answer 27

C

Question 28

using Chargaff's rules, you can determine that the DNA of an organism that contains 23% thymine would contain \_\_\_ adenine.
A. 23%
B. 27%
C. 54%
D. 77%
E. none of the above

Answer 28

A

Question 29

the proteome if all the proteins produced by an organism. the genome is the totality of all genes of an organism. you are a biologist characterizing the proteome and genome of a new organism. you determine that for this organism, its proteome is much larger than its genome. which of the following statements is/are accurate?
A. the organism is a prokaryote
B. the organism produces polycistronic transcripts
C. the organism has a spliceosome
D. transcripts produced by this organism are immediately translated
E. all of the above

Answer 29

C