BCH 5413 EXAM 1 | 118 COMPLETE
QUESTIONS AND CORRECT ANSWERS
(VERIFIED ANSWERS) | GRADED A+ |
LATEST UPDATE 2025-2026
1. In the experiment described that supports DNA as the genetic material:
a.
Why does the mouse die if the researcher mixes the completely dead pathogenic
strain with live non-pathogenic strain bacteria and then injects it into the mouse?
(The first mouse in the figure). - ANSWER - R strain has been transformed =
now S strain
---- can produce virulence factors that make the S strain deadly to mice.
-- pathogenic strain is killed, its DNA is released, and now floating freely can go
into the R strain and TRANSFORM it.
1. In the experiment described that supports DNA as the genetic material:
b.
What was the only scenario in which the mouse lives? Why? - ANSWER --
When DNA of the S strain was destroyed
-- DNA that caused the virulence factors is destroyed = no function
,2. What were the contributions of Wilkins, Franklin, Watson, and Crick to the
discovery of the structure of DNA? - ANSWER Wilkins + Franklin = crystal X
pattern of helix
Watson + Crick = model of DNA structure
3. Based on the carbon numbering system for the sugar (1 - 5) that makes up DNA,
describe the main component that is attached to each carbon and why it is
important to the structure of DNA. - ANSWER The next 5 questions are for
this...
3. In DNA, C1 is bonded to...
This is important because... - ANSWER -- a nitrogenous base (adenine,
guanine, cytosine, or thymine)
-- this allows the nitrogenous bases to form hydrogen bonds
-- A-T
-- C-G
between the 5`-3` strand and the 3`-5` strand
3. In DNA, C2 is bonded to...
This is important because... - ANSWER H
Importance - C2 does not have a hydroxyl group, which distinguishes it from RNA.
,3. In DNA, C3 is bonded to...
This is important because... - ANSWER OH
Importance - The C3 of one sugar forms a phosphodiester bond with the 5`
phosphate of another sugar.
--- makes phosphodiester chain
4. In DNA, C4 is bonded to... - ANSWER C5
5. In DNA, C5 is bonded to...
This is important because... - ANSWER phosphate
Importance - The C5 can be the lead sugar or form phosphodiester bonds with the
C3 of a second sugar.
-- This gives DNA the 5` to 3` linkage.
4. Describe why DNA has directionality. - ANSWER -- 5' end = free phosphate
group
-- 3' end = free hydroxyl (OH) group
, -- DNA is always synthesized in the 5'-to-3' direction = added only to the 3' end of
the growing strand
-- G forms 3 hydrogen bonds to C
-- A forms 2 hydrogen bonds to T
-- Sequence of DNA has an effect on the structure.
5. What is the meaning of the term antiparallel in the structure of DNA? -
ANSWER -- orientation is opposite
-- 5' - 3' polarities are in opposite directions
6. What does the Meselson and Stahl experiment confirm? - ANSWER --
complementary base pairing allows us to move that information to the next
generation of DNA
-- semi-conservative model
7. True/False:
a.
The major groove is the structure of DNA that allows for more specificity in
binding proteins - ANSWER TRUE
-- minor groove = less specific
QUESTIONS AND CORRECT ANSWERS
(VERIFIED ANSWERS) | GRADED A+ |
LATEST UPDATE 2025-2026
1. In the experiment described that supports DNA as the genetic material:
a.
Why does the mouse die if the researcher mixes the completely dead pathogenic
strain with live non-pathogenic strain bacteria and then injects it into the mouse?
(The first mouse in the figure). - ANSWER - R strain has been transformed =
now S strain
---- can produce virulence factors that make the S strain deadly to mice.
-- pathogenic strain is killed, its DNA is released, and now floating freely can go
into the R strain and TRANSFORM it.
1. In the experiment described that supports DNA as the genetic material:
b.
What was the only scenario in which the mouse lives? Why? - ANSWER --
When DNA of the S strain was destroyed
-- DNA that caused the virulence factors is destroyed = no function
,2. What were the contributions of Wilkins, Franklin, Watson, and Crick to the
discovery of the structure of DNA? - ANSWER Wilkins + Franklin = crystal X
pattern of helix
Watson + Crick = model of DNA structure
3. Based on the carbon numbering system for the sugar (1 - 5) that makes up DNA,
describe the main component that is attached to each carbon and why it is
important to the structure of DNA. - ANSWER The next 5 questions are for
this...
3. In DNA, C1 is bonded to...
This is important because... - ANSWER -- a nitrogenous base (adenine,
guanine, cytosine, or thymine)
-- this allows the nitrogenous bases to form hydrogen bonds
-- A-T
-- C-G
between the 5`-3` strand and the 3`-5` strand
3. In DNA, C2 is bonded to...
This is important because... - ANSWER H
Importance - C2 does not have a hydroxyl group, which distinguishes it from RNA.
,3. In DNA, C3 is bonded to...
This is important because... - ANSWER OH
Importance - The C3 of one sugar forms a phosphodiester bond with the 5`
phosphate of another sugar.
--- makes phosphodiester chain
4. In DNA, C4 is bonded to... - ANSWER C5
5. In DNA, C5 is bonded to...
This is important because... - ANSWER phosphate
Importance - The C5 can be the lead sugar or form phosphodiester bonds with the
C3 of a second sugar.
-- This gives DNA the 5` to 3` linkage.
4. Describe why DNA has directionality. - ANSWER -- 5' end = free phosphate
group
-- 3' end = free hydroxyl (OH) group
, -- DNA is always synthesized in the 5'-to-3' direction = added only to the 3' end of
the growing strand
-- G forms 3 hydrogen bonds to C
-- A forms 2 hydrogen bonds to T
-- Sequence of DNA has an effect on the structure.
5. What is the meaning of the term antiparallel in the structure of DNA? -
ANSWER -- orientation is opposite
-- 5' - 3' polarities are in opposite directions
6. What does the Meselson and Stahl experiment confirm? - ANSWER --
complementary base pairing allows us to move that information to the next
generation of DNA
-- semi-conservative model
7. True/False:
a.
The major groove is the structure of DNA that allows for more specificity in
binding proteins - ANSWER TRUE
-- minor groove = less specific
