Bio 208 Exam 4 final review (draper)

In the past, I have tried to give points away by asking questions such as, " The instructor for bio 208 is?". Unfortunately, there were people in the class unable to answer that question. Therefore, I have decided to try something even easier. The answer to this question is A. A) A B) B C) C D) D E) E

A) A

Which of the following is added to a spliced mRNA molecule before it leaves the nucleus? A) A 5' cap B) tRNAs C) exons D) termination codons E) initiation codons

A) A 5' cap

Which of the following, when taken up by a cell, binds to a repressor so that the repressor no longer binds to the operator? A) Inducer B) Promoter C) Repressor D) corepressor

A) Inducer

The absence of bicoid mRNA from a Drosophila egg leads to the absence of anterior larval body parts and mirror image duplication of posterior parts. This is evidence that the product of the bicoid gene? A) Normally leads to formation of head structures B) Normally leads to formation of tail structures C) Is transcribed in the early embryo D) Is a protein present in all head structures

A) Normally leads to formation of head structures

In normal (non-cancerous) human cells, cell division is stimulated by? A) Proto-oncogenes B) Oncogenes C) Tumor suppressor genes D) Lac repressor protein E) Histones

A) Proto-oncogenes

Which of the following marcromolecules is capable of storing genetic information and catalyzing enzymatic reactions? A) RNA B) B-hemoglobin C) tubulin D) alpha synucelin E) DNA

A) RNA

Which of the following elements is NOT found in DNA? A) Sulfur B) Carbon C) Nitrogen D) Phosphorous E) Oxygen

A) Sulfur

Which statement about the genetic code is FALSE? A) amino acids are encoded by 64 different codons B) there are six codons for Leucine (leu) C) codons in the genetic code are essentially identical in all living organisms D) several amino acids are encoded by more than one codon E) the start codon is usually AUG, the only codon for methionine

A) amino acids are encoded by 64 different codons

Enhancers: A) are regions of eukaryotic gene promoters that bind to transcription factors B) increase the rate of DNA sythesis at eukaryotic replication forks C) improve the fidelity of DNA polymerase (i.e. , they decrease the error rate) D) regulate which cells lose copies of certain genes during development E) none of the above

A) are regions of eukaryotic gene promoters that bind to transcription factors

If two tRNA molecules are associated with a ribosome, one attached to a polypeptide and one attached to a single amino acid, where will the tRNA with the polypeptide be found? A) in the P site B) in the A site C) In the E site D) Attached to the spliceosome E) Covalently bound to rRNA in the small ribosomal subunit

A) in the P site

How would you describe the mutation that occurred at position 3? A) missense mutation B) nonsense mutation C) silent mutation D) loud mutation E) Frameshift mutation

A) missense mutation

After one amino acid is attached by a peptide bond onto the growing polypeptide chain, the ribosome? A) moves three nucleotides forward along the mRNA B) cuts the 3-nucleotide recognition sequence from the tRNA C) moves to another mRNA and attaches the same amino acid D) initiates a new polypeptide chain E) cuts the mRNA strand that has already been read

A) moves three nucleotides forward along the mRNA

The coding region of a messenger RNA contains 1263 bases. The protein encoded by this mRNA would contain _____ amino acids. A) 0 B) 420 C) 1263 D) 3789 E) None of the above

B) 420

A group of cells that originates from a single human cell and grows in an uncontrolled way is called? A) a ganglion B) A tumor C) A somatic mutation D) Crown gall E) A transposable element

B) A tumor

In trying to determine whether DNA or protein is the genetic material, Hershey and Chase made use of which of the following facts? A) DNA contains sulfur whereas protein does not B) DNA contains phosphorus whereas protein does not C) DNA contains nitrogen whereas protein does not D) DNA contains purines whereas protein includes pyrimidines

B) DNA contains phosphorus whereas protein does not

In eukaryotic cells, transcription cannot begin until ______. A) the two DNA strands have completely separated and exposed the promoter B) Several transcription factors have bound to the promoter C) The 5' caps are removed from the mRNA D) The DNA introns are removed from the template

B) Several transcription factors have bound to the promoter

The double helix structure of DNA was described in 1953 by? A) Franklin and Wilkins B) Watson and Crick C) Meselson and Stahl D) Hershey and Chase E) Williams and Sonoma

B) Watson and Crick

A nucleosome ______. A) regulates which molecules enter and leave the nucleus B) includes 8 molecules of positively charged histone proteins C) contains the material that binds homologous chromosomes during meiosis D) is the site within the nucleus where ribosomes are synthesized E) is the DNA-containing region of a prokaryotic cell

B) includes 8 molecules of positively charged histone proteins

How would you describe the mutation at position 4? A) missense mutation B) nonsense mutation C) silent mutation D) loud mutation E) frameshift mutation

B) nonsense mutation

The elongation of the leading strand during DNA replication: A) progresses away from the replication fork B) occurs in the 5 ' -> 3 ' direction C) produces many Okazaki fragments, which subsequently are joined together D) requires spliceosomes E) all of the above

B) occurs in the 5 ' -> 3 ' direction

A mutant bacterial cell has a defective aminoacyl-tRNA synthetase that attaches a lysine to tRNAs with the anticodon AAA instead of the normal phenylalanine. The consequence of this for the cell will be that ______. A) none of the proteins in the cell will contain phenylalanine B) proteins in the cell will include lysine instead of phenylalanine at amino acid positions specified by the codon UUU C) the cell will compensate for the defect by attaching phenylalanine to tRNAs with lysine-specifying anticodons D) the ribosome will skip a codon every time a UUU is encountered

B) proteins in the cell will include lysine instead of phenylalanine at amino acid positions specified by the codon UUU

Sea urchin DNA contains about 18% guanine; how much adenine should be present? A) 16% B) 18% C) 32% D) 36% E) 64%

C) 32%

During translation, in which order do the following events occur? 1. a peptide bond is formed 2. the appropriate tRNA enters the A site 3. the ribosome moves 1 codon along the mRNA 4. initiator methionine-tRNA enters the P site A) 4,2,3,1 B) 2,4,1,3 C) 4,2,1,3 D) 1,2,3,4 E) 2,4,3,1

C) 4,2,1,3

A peptide has the sequence N-Leu-Arg-Ser-C. One mRNA sequence that corresponds to this peptide is? (this question doesnt make much sence because I cannot type the chart) A) 5'-UUG-GGG-CUU B) 5'-UAA-UAG-UGA C) 5'-CUA-CGG-AGC D) 5'-CUU-CCU-AGU E) none of the above

C) 5'-CUA-CGG-AGC

What kind of chemical bonds are found between paired bases in the DNA double helix? A) Ionic B) Franklin forces C) Hydrogen D) Covalent E) Chargaff bonds

C) Hydrogen

Which of the following peptide sequences would be generated by an mRNA with the following sequence: 5'-AUG-CGU-GAA-UGA-3' (this question doesnt make much sence because I cannot type the chart) A) C-Met-Arg-Glu-N B) C-Val-Lys-Cys-Ser-N C) N-Met-Arg-Glu-C D) N-Val-Cys-Lys-Ser-C E) none of the above

C) N-Met-Arg-Glu-C

According to the operon model of gene regulation, the repressor protein inhibits transcription by binding to the? A) DNA polymerase B) Ribosome C) Operator D) RNA polymerase E) Promoter

C) Operator

If a particular operon encodes enzymes for making an essential amino acid and is regulated like the trp operon, then? A) The amino acid inactivates the repressor B) The repressor is active in the absence of the amino acid C) The amino acid acts as a corepressor D) The amino acid turns on transcription of the operon E) None of the above

C) The amino acid acts as a corepressor

Which of the following is an example of post-transcriptional control of gene expression? A) The addition of methyl groups to cytosine bases of DNA B) The binding of transcription factors to a promoter C) The removal of introns and alternative splicing of exons D) Gene amplification contributing to cancer

C) The removal of introns and alternative splicing of exons

Not long ago it was believed that a count of the number of protein-coding genes would provide a count of the number of proteins produced in any given eukaryotic species. This is incorrect, largely due to the discovery of widespread ________. A) chromatin condensation control B) transcriptional control C) alternative splicing D) translational control

C) alternative splicing

Oncogenes are: A) always derived from viruses B) the protein products of most mutated genes C) related to cellular proto-oncogenes, which regulate normal cell growth D) mutated versions of tumor suppressor genes E) highly expressed in non-dividing cells

C) related to cellular proto-oncogenes, which regulate normal cell growth

Which of the following is directly related to a single amino acid? A) the base sequence of the tRNA B) the amino acetyl tRNA synthase C) the three base sequence of mRNA D) the complementarity of DNA and RNA

C) the three base sequence of mRNA

Cancers related to smoking and diet account for about _____ of all cancers in the United States. A) 0.2% B) 1% C) 7% D) 11% E) 66%

D) 11%

The rover Curiosity has found evidence of microbial life on Mars! This organism uses a genetic code much like that of earth organisms except that: a) there are 6 different DNA bases instead of 4; and b) the base sequences are translated as doublets instead of triplets. How many different codons (including STOPs) could be accommodated by this code? A) 4 B) 6 C) 24 D) 36 E) 1296

D) 36

The sequence of one strand of a DNA molecule is 5'-GATATC. What is the sequence of the other strand? A) 3'-GATATC B) 3'-GAUAUC C) 5'-GATATC D) 5'-CTATAG E) None of the above

D) 5'-CTATAG

Which of the following mutations would be most likely to have a harmful effect on an organism? A) A deletion of three nucleotides near the middle of a gene B) A single nucleotide deletion in the middle of an intron C) A single nucleotide deletion near the end of the coding sequence D) A single nucleotide insertion downstream of and close to the start of the coding sequence E) All of these mutations would most likely be equally harmful to the organism

D) A single nucleotide insertion downstream of and close to the start of the coding sequence

In the Messelson-Stahl experiment, bacteria were grown in media containing, 15N for many generations and then transferred to media containing 14N. After TWO rounds of DNA replication, the DNA was centrifuged in CsCl. Which statement best describes this DNA? A) All of it was of intermediate density B) All of it was heavy C) Half was heavy, half was light D) Half was light, half was intermediate density E) Half was heavy, half was intermediate density

D) Half was light, half was intermediate density

An enzyme that uses DNA as a template to synthesize a complementary RNA strand is called? A) Ligase B) Glycosidase C) Topoisomerase D) RNA polymerase E) DNA polymerase

D) RNA polymerase

Crick and Brenner's reading frame experiment ("why did the red bat...") established that ________. A) bacteria and humans use almost the same genetic code B) a change in reading frame is caused by nucleotide deletions but not by insertions C) a codon is equivalent to at least 3 amino acids D) a codon is equivalent to exactly 3 amino acids E) none of the above

D) a codon is equivalent to exactly 3 amino acids

The lac operon in E. coli: A) is turned on when the repressor binds to the operator B) is turned on when the repressor binds to the promoter C) is important for synthesizing amino acids D) is stimulated by the presence of allolactose or lactose E) is nearly identical to the lac operon found on human chromosomes

D) is stimulated by the presence of allolactose or lactose

Human cancer frequently involves? A) inactivation of both copies of a tumor suppressor gene B) migration of cancerous cells to other parts of the body C) mutation of proto-oncogenes into oncogenes D) abnormal control of the cell cycle at specific "checkpoints" E) All of the above

E) All of the above

An enzyme that joins a specific amino acid with a specific tRNA molecule is? A) DNA polymerase B) Ligase C) Aminoacyl tRNA synthetase D) Topoisomerase E) Aminoacyl tRNA reductase

E) Aminoacyl tRNA reductase

The transfer of genetic information to a new generation requires accurate replication of DNA. The structural feature of DNA most important to this process is: A) the sugar phosphate backbone B) the pairing between two purines C) Phosphodiester bonding between the helices D) Hydrogen bonding to form an alpha-helix E) Complementary pairing of bases

E) Complementary pairing of bases

The amino acid found at the C-terminus (carboxy terminus) of most proteins is? A) Glutamic acid B) Glycine C) Lysine D) Methionine E) Could be any amino acid

E) Could be any amino acid

During processing of a primary RNA transcript, _____ are joined together to form a mature mRNA molecule. A) Okazaki fragments B) Introns C) Amino acids D) Termination codons E) Exons

E) Exons

Which molecule is found in RNA but not in DNA? A) Adenine B) Deoxyribose C) Guanine D) Thymine E) Ribose

E) Ribose

Transcription of structural genes in the trp operon: A) Occurs all the time B) Starts when lactose is present C) Starts when glucose is present D) Starts when the trp repressor binds to the trp operator E) Stops when tryptophan concentration is high

E) Stops when tryptophan concentration is high

An auxotroph is ____. A) a mutant that lacks ribosomes B) a plant that cannot make auxin C) a prokaryote that eats heavy metals D) a mutant that cannot grow in the dark E) a mutant that cannot make an essential nutrient

E) a mutant that cannot make an essential nutrient

Where would one find an anticodon? A) DNA B) mRNA C) ribosomes D) RNA polymerase E) tRNA

E) tRNA

Beadle and Tatum studied several mutants of Neurospora, a bread mold. They determined that ______. A) one chromosome contains just enough information to make one enzyme B) a polypeptide is the result of the activity of one ribosome C) a gene contains the information to make one carbohydrate D) a tRNA catalyzes the production of one protein E) the information contained in one gene is sufficient to make one enzyme

E) the information contained in one gene is sufficient to make one enzyme