BCH5413 Exam 1 QUESTIONS WITH |\ |\ |\ |\ |\
ANSWERS
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). - CORRECT ANSWERS ✔✔- 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? -
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
CORRECT ANSWERS ✔✔-- 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? - CORRECT
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
ANSWERS ✔✔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. - CORRECT ANSWERS ✔✔The next 5 questions are for
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
this...
3. In DNA, C1 is bonded to...
|\ |\ |\ |\ |\ |\
This is important because... - CORRECT ANSWERS ✔✔-- 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... - CORRECT ANSWERS ✔✔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... - CORRECT ANSWERS ✔✔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... - CORRECT ANSWERS ✔✔C5
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\
5. In DNA, C5 is bonded to...
|\ |\ |\ |\ |\ |\
This is important because... - CORRECT ANSWERS ✔✔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. - CORRECT ANSWERS
|\ |\ |\ |\ |\ |\ |\ |\ |\
✔✔-- 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? - CORRECT ANSWERS ✔✔-- orientation is opposite
|\ |\ |\ |\ |\ |\ |\ |\
-- 5' - 3' polarities are in opposite directions
|\ |\ |\ |\ |\ |\ |\ |\
6. What does the Meselson and Stahl experiment confirm? -
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\
CORRECT ANSWERS ✔✔-- complementary base pairing allows us |\ |\ |\ |\ |\ |\ |\ |\
to move that information to the next generation of DNA
|\ |\ |\ |\ |\ |\ |\ |\ |\
-- semi-conservative model
|\ |\
7. True/False:
|\ |\
a.
ANSWERS
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). - CORRECT ANSWERS ✔✔- 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? -
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
CORRECT ANSWERS ✔✔-- 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? - CORRECT
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
ANSWERS ✔✔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. - CORRECT ANSWERS ✔✔The next 5 questions are for
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\ |\
this...
3. In DNA, C1 is bonded to...
|\ |\ |\ |\ |\ |\
This is important because... - CORRECT ANSWERS ✔✔-- 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... - CORRECT ANSWERS ✔✔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... - CORRECT ANSWERS ✔✔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... - CORRECT ANSWERS ✔✔C5
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\
5. In DNA, C5 is bonded to...
|\ |\ |\ |\ |\ |\
This is important because... - CORRECT ANSWERS ✔✔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. - CORRECT ANSWERS
|\ |\ |\ |\ |\ |\ |\ |\ |\
✔✔-- 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? - CORRECT ANSWERS ✔✔-- orientation is opposite
|\ |\ |\ |\ |\ |\ |\ |\
-- 5' - 3' polarities are in opposite directions
|\ |\ |\ |\ |\ |\ |\ |\
6. What does the Meselson and Stahl experiment confirm? -
|\ |\ |\ |\ |\ |\ |\ |\ |\ |\
CORRECT ANSWERS ✔✔-- complementary base pairing allows us |\ |\ |\ |\ |\ |\ |\ |\
to move that information to the next generation of DNA
|\ |\ |\ |\ |\ |\ |\ |\ |\
-- semi-conservative model
|\ |\
7. True/False:
|\ |\
a.
