quiz 3 Flashcards
A supportive cell (may contain specific receptors) that allows the complete replication cycle of a virus to take place is said to be
A. lytic cell
B. dead cell
C. permissive host
D. viral cell
C. permissive host
Reverse transcriptase is a(n)
A. RNA-dependent DNA polymerase
B. DNA-dependent RNA polymerase
C. RNA-dependent RNA polymerase
D. DNA-dependent DNA polymerase
A. RNA-dependent DNA polymerase
How are plasmids different than chromosomes?
A. plasmids are always small, linear pieces of DNA
B. plasmids are composed of single-stranded DNA
C. plasmids carry unimportant genes that are of little significance for the ecology and metabolism of an organism
D. plasmids contain genes that are NOT essential for cellular growth
D. plasmids contain genes that are NOT essential for cellular growth
Supercoiling is important for DNA structure because
A. it provides energy for transcription
B. it holds together antiparallel strands of DNA in the double helix
C. it condenses the DNA so that it can fit inside the cell
D. it prevents RNA from pairing with DNA in the double helix
C. it condenses the DNA so that it can fit inside the cell
The codon on the ___ matches with the anticodon on the ___ to direct the addition of the correct amino acid to the growing polypeptide chain.
A. tRNA/mRNA
B. DtRNA/rRNA
C. mRNA/tRNA
D. DNA/mRNA
C. mRNA/tRNA
An operon is a useful genetic element because it
A. allows coordinated expression of multiple related genes in prokaryotes
B. translates DNA sequence into amino acid sequence
C. encourages the binding of ribosomes in the correct location
D. encourages the binding of RNA polymerase
A. allows coordinated expression of multiple related genes in prokaryotes
In nature, the predominant form of DNA is supercoiled in a negative direction
T/F
T
The functional unit of genetic information is the
A. protein
B. chromosome
C. nucleotide
D. gene
D. gene
What does the COVID-19 virus attach itself to when it enters the human body?
A. LDL receptors in the lining of the airways
B. RBC
C. Ace-2 receptors in the lining of the airways
D. antigens
C. Ace-2 receptors in the lining of the airways
An alteration in the DNA of an organism is called a(n):
A. hereditary maker
B. replicon
C. mutation
D. allele
C. mutation
The Meselson-Stahl experiment demonstrated that DNA replication produces 2 DNA molecules, each composed of
A. one old strand and one new strand
B. two new strands
C. two old strands
D. two strands with variable proportions of new and old DNA
A. one old strand and one new strand
The function of the DNA polymerase is to catalyze
A. the formation of RNA primers
B. the addition of ribonucleotides
C. hydrogen bonding between complementary base pairs
D. the addition of deoxynucleotides
D. the addition of deoxynucleotides
Many pharmaceutical drugs specifically inhibit transcription in Bacteria but not Archaea or Eukarya. Why would drugs that inhibit transcription only affect Bacteria and not Archaea, even though they are both prokaryotes?
A. bacteria lack a nucleus.
B. archaea and Eukarya have very similar ribosomes that are different than bacterial ribosomes.
C. archaea and Eukarya have very similar RNA polymerases that are different than bacterial RNA polymerases.
D. archaea lack operons.
C. archaea and Eukarya have very similar RNA polymerases that are different than bacterial RNA polymerases.
Which statement is not true about the finding in the Watson and Crick Nature paper describing the Molecular Structure of Nucleic acids?
A. unlikely to build this structure with a ribose sugar in place of the deoxyribose, because the extra oxygen atom would make too close for van der Waal forces
B. this structure has two helical chains each coiled round the same axis.
C. the phosphodiester bond is the linkage between the 3’ carbon atom of one sugar molecule and the 5’ carbon atom of another, deoxyribose.
D. the planes of the bases are parallel to the fiber axis.
D. the planes of the bases are parallel to the fiber axis.
Enveloped viral membranes are generally ________ with associated virus-specific ________.
A. glycolipid bilayers / phospholipids
B. lipid bilayers / phospholipids
C. phospholipid bilayers / proteins
D. protein bilayers / lipids
C. phospholipid bilayers / proteins
