INSTRUCTIONS:
Write your name and netID on the first page of the question packet, and on the ANSWER SHEET.
No answers in the question packet will be graded, you must write all answers on the answer
sheet. You may use the question packet for scrap. You may write in pen or pencil.
Note that some useful ∆G values, chemical details of base pairing, measures corresponding to
units of length (e.g. nm, um, etc.), and a table of amino acid structures can be found on the last
page of this exam.
You can ONLY select multiple answers on questions clearly marked “SELECT ANY THAT APPLY”
(“SELECT ANY THAT APPLY” questions may have one or more correct answers; never 0, unless
“none of these” is an option). These questions receive partial credit for each correctly
selected/unselected option, unless they’re left blank.
Any questions requiring a numeric answer can be written as either the final number or as an
unreduced equation that gives the right answer (e.g. ½*4 instead of 2 is fine).
Each short question is worth 2 points, except questions 1-2, which are worth 1 point each; each
‘long’ question is worth 8 points total.
For questions 1-2, answers will be graded on completion (these are give-away questions as long
as you answer them!) Your responses will only be used to get a better idea of how much
background students in the class come in with.
1. Which of the following best describes your previous experience with biology?
A. High school biology or less
B. Took AP/IB Biology
C. Other
2. Which of the following best describes your previous experience with chemistry? (SELECT
ANY THAT APPLY)
A. High school chemistry or less, not currently taking chemistry
B. Currently taking Chemistry 1
C. Completed Chemistry 1
D. Currently taking organic chemistry
, BIOL-UA 11 F25
*THIS SHEET WILL NOT BE GRADED* Midterm 1A
SHORT QUESTIONS
3. How many hydrogens are there in the molecule shown below? 12
4. Which of these DNA molecules will require the MOST heat to separate the strands?
A. CTGGGG
B. AAGCTA
C. GCCAAT
D. AATGAT
E. Impossible to determine from the information provided
5. You identify a new organism and find that 20% of its DNA is either A or T. What percent
of its DNA is G? (Just write the number.) (100-20)/2 = 40%
Concerned about wording on this question – everyone gets points on this one.
6. Which of the following molecules is definitely NOT RNA?
A. 5’ AGACGA 3’ C. 5’ UAGCCU 3’
B. D. ONLY THIS
2
, Name: netID (e.g. yp19): BIOL-UA 11 F25
Midterm 1
*THIS SHEET WILL NOT BE GRADED*
Use the image below, of a protein bound to a DNA molecule, to answer the following two
questions:
7. What kind of
structure(s) do you observe in this protein?
A. Alpha helix
B. Beta sheet
C. Both alpha helix
and beta sheet
D. No structure –
this protein is disordered
8. What kind of bond is responsible specifically for making each of the protein components
you see be shaped as a spiral?
A. Covalent bonds between r-groups
B. Covalent bonds between atoms in the backbone
C. Hydrogen bonds between r-groups
D. Hydrogen bonds between atoms in the backbone
E. Hydrophobic bonds between r-groups
F. Hydrophobic bonds between atoms in the backbone
9. Recall that in sickle cell anemia, a glutamic acid is replaced with a valine in a position
near the surface of the hemoglobin protein, causing aggregation of hemoglobin proteins
inside red blood cells. Which of the following accurately describes the
biophysical/chemical effect that is causing this aggregation?
A. An increase in hydrophobic interactions
B. An increase in hydrophilic interactions
C. An increase in ionic interactions
D. An increase in disulfide bond number
3
Write your name and netID on the first page of the question packet, and on the ANSWER SHEET.
No answers in the question packet will be graded, you must write all answers on the answer
sheet. You may use the question packet for scrap. You may write in pen or pencil.
Note that some useful ∆G values, chemical details of base pairing, measures corresponding to
units of length (e.g. nm, um, etc.), and a table of amino acid structures can be found on the last
page of this exam.
You can ONLY select multiple answers on questions clearly marked “SELECT ANY THAT APPLY”
(“SELECT ANY THAT APPLY” questions may have one or more correct answers; never 0, unless
“none of these” is an option). These questions receive partial credit for each correctly
selected/unselected option, unless they’re left blank.
Any questions requiring a numeric answer can be written as either the final number or as an
unreduced equation that gives the right answer (e.g. ½*4 instead of 2 is fine).
Each short question is worth 2 points, except questions 1-2, which are worth 1 point each; each
‘long’ question is worth 8 points total.
For questions 1-2, answers will be graded on completion (these are give-away questions as long
as you answer them!) Your responses will only be used to get a better idea of how much
background students in the class come in with.
1. Which of the following best describes your previous experience with biology?
A. High school biology or less
B. Took AP/IB Biology
C. Other
2. Which of the following best describes your previous experience with chemistry? (SELECT
ANY THAT APPLY)
A. High school chemistry or less, not currently taking chemistry
B. Currently taking Chemistry 1
C. Completed Chemistry 1
D. Currently taking organic chemistry
, BIOL-UA 11 F25
*THIS SHEET WILL NOT BE GRADED* Midterm 1A
SHORT QUESTIONS
3. How many hydrogens are there in the molecule shown below? 12
4. Which of these DNA molecules will require the MOST heat to separate the strands?
A. CTGGGG
B. AAGCTA
C. GCCAAT
D. AATGAT
E. Impossible to determine from the information provided
5. You identify a new organism and find that 20% of its DNA is either A or T. What percent
of its DNA is G? (Just write the number.) (100-20)/2 = 40%
Concerned about wording on this question – everyone gets points on this one.
6. Which of the following molecules is definitely NOT RNA?
A. 5’ AGACGA 3’ C. 5’ UAGCCU 3’
B. D. ONLY THIS
2
, Name: netID (e.g. yp19): BIOL-UA 11 F25
Midterm 1
*THIS SHEET WILL NOT BE GRADED*
Use the image below, of a protein bound to a DNA molecule, to answer the following two
questions:
7. What kind of
structure(s) do you observe in this protein?
A. Alpha helix
B. Beta sheet
C. Both alpha helix
and beta sheet
D. No structure –
this protein is disordered
8. What kind of bond is responsible specifically for making each of the protein components
you see be shaped as a spiral?
A. Covalent bonds between r-groups
B. Covalent bonds between atoms in the backbone
C. Hydrogen bonds between r-groups
D. Hydrogen bonds between atoms in the backbone
E. Hydrophobic bonds between r-groups
F. Hydrophobic bonds between atoms in the backbone
9. Recall that in sickle cell anemia, a glutamic acid is replaced with a valine in a position
near the surface of the hemoglobin protein, causing aggregation of hemoglobin proteins
inside red blood cells. Which of the following accurately describes the
biophysical/chemical effect that is causing this aggregation?
A. An increase in hydrophobic interactions
B. An increase in hydrophilic interactions
C. An increase in ionic interactions
D. An increase in disulfide bond number
3
