Download Bio 103 Practice Quiz 1

Bio 103 Practice Quiz – Chapter 8
Name_____________________
Turn in both quizzes for two extra points on Exam 5
1. Because each base pairs with a complementary base, in every DNA molecule the amount of
a. cytosine equals that of guanine.
b. cytosine equals that of thymine.
c. cytosine equals that of adenine.
d. each nucleotide is unrelated to all others.
e. each nucleotide is equal to all others.
2. Semiconservative replication refers to the fact that:
a. each new DNA molecule contains two new single DNA strands.
b. DNA polymerase uses free nucleotides to synthesize new DNA molecules.
c. certain bases pair with specific bases.
d. each parental DNA strand is joined with a new strand containing complementary base pairs.
e. mistakes are made during DNA replication.
3. Which of the following are INCORRECTLY matched?
a. Complementary base pairs: adenine and cytosine
b. Bases: adenine, thymine, cytosine, and guanine
c. Nucleotide: phosphate and sugar and base
d. Eukaryotic chromosome: DNA and protein
e. Enzymes involved in DNA replication: DNA polymerase and DNA helicase
4. Which component of a nucleotide, present within a DNA molecule, could be removed without breaking the
polynucleotide chain?
a. ribose
b. deoxyribose
c. phosphate
d. uracil
e. thymine
5. What is the relationship among DNA, a gene, and a chromosome?
a. A chromosome contains hundreds of genes which are composed of protein.
b. A chromosome contains hundreds of genes which are composed of DNA.
c. A gene contains hundreds of chromosomes which are composed of protein.
d. A gene is composed of DNA, but there is no relationship to a chromosome.
e. A gene contains hundreds of chromosomes which are composed of DNA.
6. Which of the following can cause errors to accumulate in DNA?
a. High levels of metabolic activity
b. Ultraviolet light
c. Cold temperatures
d. A lack of water and oxygen
7. How many different three-base sequences can be assembled using the four nucleotides found in DNA?
a. 1
b. 3
c. 9
d. 64
e. more than 64
8. What is the function of DNA polymerase in DNA replication?
a. Destroy old DNA
b. Synthesize new DNA strands
c. Join together segments of DNA
d. Separate the 2 parental DNA strands
e. None of the above
9. A forensic scientist determining whether DNA found at a scene matches that of a suspect would be most
interested in the suspect’s __________.
a. DNA sequence
b. Proportion of A, C, T, and G bases
c. Hair color
d. Chromosome size
e. Number of DNA bases
10. If a base sequence contains 20% adenine, what is the percentage of guanine?
a. 20%
b. 30%
c. 40%
d. 50%
e. 80%
Bio 103 Practice Quiz – Chapter 9
Name_____________________
Turn in both quizzes for two extra points on Exam 5
1. When comparing DNA and RNA, we find
a. no sugar is present in either molecule.
b. hydrogen bonding is important only in DNA.
c. only DNA has a backbone of sugars and phosphates.
d. adenine pairs with different bases in DNA and RNA.
e. thymine pairs with different bases in DNA and RNA.
2. A "mini-gene" has the following sequence: TACCCGTGCACG. What is the consequence if the T at the
beginning of the sequence is deleted?
a. All of the codons after that point will be changed.
b. Only the amino acid encoded by that codon will be changed.
c. RNA polymerase will skip that codon, but all the others will be read normally.
d. RNA polymerase will correct the deletion and a normal protein will be produced.
e. The first nucleotide is not important, so there will be no change.
3. Imagine that the template strand of a gene has the sequence TAC. After RNA is made, what sequence of the
anticodon would decode this?
a. ATG, because the anticodon is complementary to the template strand.
b. AUG, because the anticodon is complementary to the template strand (but it has U instead of T).
c. UAC, because the anticodon has the same sequence as the template strand (but it has U instead of T).
d. TAC, because the anticodon has the same sequence as the template strand.
4. Imagine that a probe sent to Mars brings back a sample. It contains a very primitive life-form that appears
similar to bacteria. Scientists are able to revive it and begin to grow it in culture. Much to their amazement, the
DNA of these Martian microbes contains only two nucleotides, and these nucleotides contain bases that are not
present in the DNA of organisms on Earth. If the Martian microbe uses a triplet code, what is the maximum
number of different amino acids that it can have in its proteins?
a. 9, because 32 = 3 x 3 = 9
b. 16, because 42 = 4 x 4 = 16
c. 8, because 23 = 2 x 2 x 2 = 8
d. 7, because there are 8 possible codons (23 = 2 x 2 x 2 = 8) but at least one of the codons must be a stop.
5. What is the promoter region?
a. It is a region of RNA that binds to the RNA polymerase and initiates transcription.
b. It is a component of each type of RNA.
c. It is responsible for the selective nature of transcription.
d. It is a region of a parent DNA strand that binds to the RNA polymerase to initiate transcription.
6. Which of the following is NOT a means of regulating gene expression?
a. Regulating the life span of a protein
b. Modifying proteins after they are synthesized
c. Varying the rate at which messenger RNAs are translated
d. Varying the rate at which messenger RNAs are transcribed
e. Deleting genes from cells in which they are not needed
7. What kind of mutation would have the most dramatic effect on the protein encoded by that gene?
a. A base substitution
b. A base insertion near the beginning of the coding sequence
c. A base insertion near the end of the coding sequence
d. Deletion of three bases near the start of the coding sequence
8. Which of the following is NOT true about RNA molecules?
a. rRNA and certain proteins together make up the ribosomes
b. tRNAs are translated in the cytoplasm of eukaryotic cells
c. mRNAs are transcribed in the nucleus of eukaryotic cells
d. mRNAs are translated in the cytoplasm of eukaryotic cells
9. How can a gene be mutated with no resulting change in the protein that is produced from that gene?
a. The mutation is in the active site of the protein.
b. A codon has changed, but it codes for the same amino acid as the original codon.
c. An entire codon has been removed.
d. RNA polymerase can edit the mutation from the mRNA produced during translation.
e. This is impossible. All mutations, by definition, result in altered proteins.
10. Of the following types of mutations, which is considered the LEAST drastic?
a. insertion of one base
b. deletion of two bases
c. a neutral base substitution
d. a stop codon
e. a substitution of a hydrophilic amino acid for a hydrophobic one