Bio 243 Lab Final Exam- University of
Calgary Winter UPDATED Questions and
CORRECT Answers
What is DNA? - CORRECT ANSWER✔✔- DNA is a biomolecule which contains the
genetic blueprint for all living organisms.
What is the DNA chain made of? What are the parts? - CORRECT ANSWER✔✔- The DNA
chain is made of deoxyribonucleotides. The three parts are N-bases, sugar, and phosphate
group(s).
Name the pyrimidines. How many ring structures do they have? - CORRECT ANSWER✔✔-
Thymine and Cytosine. They are single ring structures.
Name the purines. How many ring structures do they have? - CORRECT ANSWER✔✔-
Adenine and Guanine. They are double ring structures.
How many hydrogen bonds does adenine and thymine have? - CORRECT ANSWER✔✔-
Two
How many hydrogen bonds does cytosine and guanine have? - CORRECT ANSWER✔✔-
Three
Through which bond are the P-group and the N-base bonded to the sugar? and on which
carbon? - CORRECT ANSWER✔✔- Through covalent bonding. For the N-base, it bonds
onto the C-1' and for the P- group, it bonds onto the C-5'.
Which bond joins the two strands of DNA together? - CORRECT ANSWER✔✔- Hydrogen
bonds
What does one nucleotide consist of? - CORRECT ANSWER✔✔- A sugar, one base, and a
phosphate group.
, What is the phosphodiester bond? Characteristics? Direction? - CORRECT ANSWER✔✔- It
is when deoxyribonucleotides get joined together through covalent bonds. It goes from 5'-3',
and you add new nucleotides to the 3' end of the previous nucleotide present in the DNA
chain. It is important for DNA replication to start, and is catalyzed by DNA polymerases.
What is the external structures of the DNA responsible for? - CORRECT ANSWER✔✔-
DNA synthesis, gives a framework for supporting the overall structure of the DNA molecule.
What is the internal structures of the DNA responsible for? - CORRECT ANSWER✔✔-
Storage of genetic information in the N bases, central dogma.
What does the DNA polymerase do? - CORRECT ANSWER✔✔- Takes a single nucleotide
from the template strand and creates complementary nucleotides.
How is the antiparallel nature of DNA made? - CORRECT ANSWER✔✔- It is a result of the
hydrogen bonding interactions between the nitrogen bases. It occurs when a base has to pair
itself with another base at the 3' end, which is opposite.
What is the anti conformation of DNA? - CORRECT ANSWER✔✔- When the rotation
around the covalent bond between the nitrogen base and sugar cause the nitrogen base to lie
flat, instead of being upright.
How does DNA fit into a nucleus in eukaryotes? - CORRECT ANSWER✔✔- It wounds
itself around positively charged histone proteins and helps fold DNA into chromatin.
In order to extract the DNA from the strawberry, we added detergent (NaCl). Why? -
CORRECT ANSWER✔✔- The detergent consists of Na+ and Cl-. The Na+ reacts with the
negatively charged DNA, whereas the Cl- reacts with the positively charged histones to
neutralize that interaction, and release the DNA.
Why was isopropanol added to the solution, containing strawberry and detergent? -
CORRECT ANSWER✔✔- Since the DNA was present at the same time as sodium, and since
both are highly soluble in water (both being polar), it was added to decrease that polarity
(make it less soluble in water), making DNA easier to extract.
Calgary Winter UPDATED Questions and
CORRECT Answers
What is DNA? - CORRECT ANSWER✔✔- DNA is a biomolecule which contains the
genetic blueprint for all living organisms.
What is the DNA chain made of? What are the parts? - CORRECT ANSWER✔✔- The DNA
chain is made of deoxyribonucleotides. The three parts are N-bases, sugar, and phosphate
group(s).
Name the pyrimidines. How many ring structures do they have? - CORRECT ANSWER✔✔-
Thymine and Cytosine. They are single ring structures.
Name the purines. How many ring structures do they have? - CORRECT ANSWER✔✔-
Adenine and Guanine. They are double ring structures.
How many hydrogen bonds does adenine and thymine have? - CORRECT ANSWER✔✔-
Two
How many hydrogen bonds does cytosine and guanine have? - CORRECT ANSWER✔✔-
Three
Through which bond are the P-group and the N-base bonded to the sugar? and on which
carbon? - CORRECT ANSWER✔✔- Through covalent bonding. For the N-base, it bonds
onto the C-1' and for the P- group, it bonds onto the C-5'.
Which bond joins the two strands of DNA together? - CORRECT ANSWER✔✔- Hydrogen
bonds
What does one nucleotide consist of? - CORRECT ANSWER✔✔- A sugar, one base, and a
phosphate group.
, What is the phosphodiester bond? Characteristics? Direction? - CORRECT ANSWER✔✔- It
is when deoxyribonucleotides get joined together through covalent bonds. It goes from 5'-3',
and you add new nucleotides to the 3' end of the previous nucleotide present in the DNA
chain. It is important for DNA replication to start, and is catalyzed by DNA polymerases.
What is the external structures of the DNA responsible for? - CORRECT ANSWER✔✔-
DNA synthesis, gives a framework for supporting the overall structure of the DNA molecule.
What is the internal structures of the DNA responsible for? - CORRECT ANSWER✔✔-
Storage of genetic information in the N bases, central dogma.
What does the DNA polymerase do? - CORRECT ANSWER✔✔- Takes a single nucleotide
from the template strand and creates complementary nucleotides.
How is the antiparallel nature of DNA made? - CORRECT ANSWER✔✔- It is a result of the
hydrogen bonding interactions between the nitrogen bases. It occurs when a base has to pair
itself with another base at the 3' end, which is opposite.
What is the anti conformation of DNA? - CORRECT ANSWER✔✔- When the rotation
around the covalent bond between the nitrogen base and sugar cause the nitrogen base to lie
flat, instead of being upright.
How does DNA fit into a nucleus in eukaryotes? - CORRECT ANSWER✔✔- It wounds
itself around positively charged histone proteins and helps fold DNA into chromatin.
In order to extract the DNA from the strawberry, we added detergent (NaCl). Why? -
CORRECT ANSWER✔✔- The detergent consists of Na+ and Cl-. The Na+ reacts with the
negatively charged DNA, whereas the Cl- reacts with the positively charged histones to
neutralize that interaction, and release the DNA.
Why was isopropanol added to the solution, containing strawberry and detergent? -
CORRECT ANSWER✔✔- Since the DNA was present at the same time as sodium, and since
both are highly soluble in water (both being polar), it was added to decrease that polarity
(make it less soluble in water), making DNA easier to extract.
