1 DNA Structure
What is/are the structural difference(s) between DNA and RNA?
A) RNA is a single-stranded nucleic acid
B) RNA nucleotides have a thymine base instead of an uracil base
C) DNA has a deoxyribose sugar instead of a ribose sugar like RNA
D) Both A and C
What are the nucleobases classified as purines?
A) Guanine, adenine, and uracil
B) Thymine and cytosine
C) Uracil, thymine, and adenine
D) Guanine and adenine
What type of bond holds the sugar-phosphate backbone together?
A) Hydrogen bond
B) Ionic bond
C) Phosphodiester bond
D) None of the above
Which of the following statements is FALSE regarding nucleotide function?
A) They function as a primary source of energy
B) They carry chemical energy in their easily hydrolyzed phosphoanhydride bonds
C) They combine with other groups to form coenzymes
D) They are used as signaling molecules in the cell
In RNA, __________ nitrogenous base replaces ________?
A) Uracil, thymine
B) Thymine, uracil
C) Uracil, cytosine
D) Cytosine, uracil
How many base pairs, per turn, form the double-stranded DNA helix?
Chromosomes are composed of which of the following?
A) DNA, proteins, and RNA
B) DNA and covalent bonds
C) RNA and proteins
D) DNA and proteins
What bonds link nucleotide bases together?
A) Ionic bonds
B) Hydrogen bonds
C) Covalent bonds
D) Polar covalent bonds
Which of the following is NOT a level of DNA packaging to fit in the nucleus?
A) Chromatin fiber
C) Intermediate filaments
D) Highly ordered structures
Which of the following characteristics is true regarding heterochromatin?
A) Not expressed
B) Less compact
C) In the form of fibers and looped domains
D) Make up about 90% of the genome
Formation of chromatin fibers requires the presence of which histone protein?
A) Histone H2A
B) Histone H1
C) Histone H4
D) Histone H2B
Which of the following is NOT a core histone protein?
A) Histone H3
B) Histone H4
C) Histone H1
D) Histone H2B
Each strand of DNA is held together by what kind of bonds?
A) Peptide bonds
B) Covalent bonds
C) Hydrogen bonds
D) Van der Waals forces
DNA is composed of:
A) Two complementary polynucleotide chains
B) Ribonucleic acids
C) Two strands of DNA that run parallel to each other
D) Polymer of amino acids
Which of the following is NOT apart of chromosome?
A) Origin of replication
A) Do NOT provide information about genetic defects within a species
B) Provide a relationship between gene number and chromosome number
C) Provide a relationship between chromosome number and genome size
D) Are the number and visual appearance of the chromosomes in the cell nuclei of an organism or species
Each chromosome has:
A) One origin of replication
B) Multiple centromeres
C) Multiple origins of replication
D) One telomere
What is/are the structural difference(s) between RNA and DNA?
A) RNA pairs bases Adenine-Thymine and Guanine-Cytosine
B) RNA is a double stranded nucleic acid
C) Apart from mitochondrial DNA, DNA is only found in the nucleus
D) The sugar in DNA is ribose
What is the difference between heterochromatin and euchromatin?
A) Euchromatin is less compact
B) Heterochromatin is expressed whereas euchromatin is not expressed
C) Euchromatin is found predominantly in telomeres and centromeres
D) Heterochromatin makes up most of the genome
Bases from each DNA strand are linked by:
A) Covalent bonds
B) Ionic bonds
C) Van der Waals forces
D) Hydrogen bonds
In DNA, adenine is paired with thymine and guanine is paired with cytosine. The bases in RNA are identical, except for which one?
A) Adenine is replaced with Uracil
B) Thymine is replaced with Ubiquinone
C) Adenine binds to Guanine
D) Thymine is replaced with Uracil
In the nucleosome:
A) This condensed region of DNA provides an attachment point for the spindle apparatus during cell division that pulls chromatids apart
B) Replication of DNA is initiated
C) DNA is wound around histone proteins
D) There are repeating sequences of DNA to protect the DNA from damage