You and your lab partner have found a living organism and it contains
membranes and DNA. You would classify this organism as
A) eukaryote
B) prokaryote
C) plant
D) you cannot classify the organism based on the information
Answer: D
A signal sequence can best be described as
A) cAMP
B) A stretch of amino acids typically 15-60 subunits in length
C) DAG
D) A and B
Answer: B
Transport of a newly synthesized protein into a nucleus requires
A) an antiporter
B) movement through a membrane translocator
C) movement through a nuclear pore
D) a symporter
Answer: C
Which of the following is part of the glycalyx?
A) a glycolipid
B) a glycoprotein
C) a phospholipid
D) A and B
C) A, B and C
Answer: D
The DNA in your skin cells is found in
A) the nucleus
B) the mitochondrion
C) the chloroplast
D) A and C
E) A and B
F) A, B, C
Answer: E
Proteins transported from the cytoplasm to the chloroplast matrix are
A) moved in the folded state via a PORIN
B) moved via a symporter
C) moved via an antiporter
D) unfolded
E) B and C
Answer: D
The most common lipid in a human cell is
A) glycosphingolipids
B) phospholipids
C) sphingosine
D) leucine
Answer: B
The N-terminal end of a functional chloroplast matrix protein has the
same N-terminus as the cytosolic form
A) True
B) False
Answer: B
False
Which of the following may increase membrane fluidity?
A) an increase in unsaturation
B) a decrease in fatty acid length
C) a decrease in cholesterol
D) B and C
E) all of the above
Answer: E
Where does glycolysis occur in a eukaryotic cell?
A) mitochondrion
B) cytoplasm
C) nucleus
D) all of the above
E) both A and B
Answer: B
Deletion of a mitochondrial signal sequence will probably result in
A) a cytosolic protein
B) a nuclear protein
C) a secreted protein
D) no protein
Answer: A
You and your lab partner are growing a cell line in the presence of
glucose. When your lab partner adds a drug that mimics the presence of
citrate it will
A) inhibit the conversion of dihydroxyacetone to glyceraldehyde-3-phosphate
B) decrease activity to phosphofructokinase
C) increase activity of phosphofructokinase
D) directly inhibit electron transport
Answer: B
The CO2 membrane transporter is more prevalent in cells
that line the lung
A) True
B) False
Answer: B
False
FADH2 is produced during
A) TCA cycle
B) Fatty acid metabolism
C) glycolysis
D) A and B
E) B and C
D) all of the above
Answer: E
You have mutated a gene so that one of three stop transfer sequences
of the protein product is eliminated. This will most likely result in
A) a lumen protein
B) a cytosolic protein
C) misplacement of the protein in the membrane
D) a mitochondrial protein
Answer: C
Metabolism of fats in a typical human cell involves
A) mitochondria
B) production of acetyl CoA
C) A and B
D) none of the above
Answer: C
A typical mitochondrion is about
A) 1000 microns
B) 100 microns
C) 1 micron
D) 0.01 microns
Answer: C
You have recently discovered a way to label vesicles that are leaving
the ER. Where do you hypothesize that the label will appear next as
cell development progresses?
A) the trans-Golgi
B) the cis-Golgi
C) the membrane
D) the endosome
E) the nucleus
Answer: B
The hydrolysis of ATP in the cytoplasm
A) has a delta G of zero
B) has a very positive delta G
C) has a very negative delta G
D) delta G cannot be measured for this reaction
Answer: C
You have created an antibody that binds the protein clathrin. When
you use this antibody to purify material from a cell culture what
would you expect to isolate?
A) newly formed vesicles
B) mitochondria
C) nuclei
D) B and C
E) targets
Answer: A
You have homogenized a plasma membrane and mixed it with oil and
water. You would expect the fatty acids to orient with the
A) Water layer
B) oil layer
C) gated transporter
D) not in a layer
Answer: B
The variations in the physical characteristics between different
proteins are influenced by the overall amino acid compositions, but
even more important is the unique amino acid _________.
A) number
B) shape
C) orientation
D) sequence
Answer: D
How many acetyl CoA molecules are produced from one glucose following glycolysis
A) four
B) three
C) two
D) one
Answer: C
The following happens when a G-protein-coupled receptor activates a G protein
A) the beta subunit exchanges its bound GDP for GTP
B) the GDP bound to the alpha subunit is phosphorylated to form
bound GTP
C) the alpha subunit exchanges its bound GDP for GTP
D) it activates the alpha subunit and inactivates the beta complex
Answer: C
How many CO2 molecules are produced during lactate
fermentation from a single pyruvate?
A) 0
B) 1
C) 2
D) 3
Answer: A
To study how proteins fold, scientists must be able to purify the
protein of interest, use solvent to denature the folded protein, and
observe the process of refolding at successive time points. What is
the effect of the solvents used in the denaturation process?
A) The solvents break some of the noncovalent interactions,
resulting in a misfolded protein
B) the solvents create a new protein conformation
C) the solvents break all covalent interactions
D) the solvents break all noncovalent interactions
Answer: D
Where does the TCA cycle occur in the typical eukaryotic cell?
A) chloroplast
B) cytoplasm
C) mitochondrion
D) B and C
E) A, B and C
Answer: C
Which of the following can passively move across the plasma membrane?
H+
Water
Cl-
O2
CO2
Mg+
Answer:
H+ - active
Water - passive
Cl-- - active
O2 - passive
CO2 - passive
Mg+ - active
A cell that constantly secretes a hormone can best be described as
A) regulated
B) constitutive
C) busy
D) steroidl
Answer: B
You stick your finger with a pin. The inflammation that results is an
example of a
A) endocrine signal
B) neuronal signal
C) paracrine signal
D) contact-dependent signal
Answer: C
A chemical that inhibits ATP proton pump will result in
A) a higher pH in the vacuole
B) a lower pH in the vacuole
C) have no effect on the pH of the vacuole
D) decreased Na+ in the vacuole
E) elevated Na+ in the vacuole
Answer: A
Which of the following is NOT a direct product of fatty acid metabolism?
A) FADH2
B) ATP
C) NADH
D) Acetyl CoA
E) None of the above, all are directly produced by fatty acid metabolism
Answer: B
Which of the following molecules is transported into the mitochondrion?
A) fatty acids
B) pyruvate
C) acetyl CoA
D) A and B
E) B and C
F) all of the above
Answer: E
True or False
1) Peptide bonds are the only covalent bonds that can link together
two amino acids in proteins
2) The polypeptide backbone is free to rotate within each peptide bond
3) Nonpolar amino acids tend to be found in the interior of proteins
4) The sequence of the atoms in the polypeptide backbone varies
between different proteins
Answer:
1) False
2) False
3) True
4) False
An example of a fast response to an extracellular signal is
A) Ca2+
B) GTP
C) synthesis of a membrane protein
D) production of mRNA
E) A and B
F) C and D
Answer: E
Which of the following channels would not be expected to generate a
change in voltage by movement of its substrate across the membrane
where it is found?
A) an aquaporin
B) a sodium channel
C) a calcium channel
D) a proton channel
Answer: A
An example of a slow response to an extracellular signal is
A) synthesis of a membrane protein
B) Ca2+ release
C) production of mRNA
D) GTP binding
E) A and B
F) C and D
Answer: F
True or False
Ras is similar to a G-protein in that it can bind GTP
Answer: True
A typical eukaryotic cell is about
A) 2000 um
B) 200 um
C) 20 um
D) 0.2 um
Answer: C
Most G-proteins are in the "on" position when bound to
A) GTP
B) ATP
C) cAMP
D) Ca2+
Answer: A
Which molecule in each pair is more likely to diffuse through the
lipid bilayer?
1) amino acids or benzene
2) Cl- or ethanol
3) Glycerol or RNA
4) H2O or O2
5) CO2 or ATP
Answer:
1) benzene
2) ethanol
3) Glycerol
4) O2
5) CO2
Active G-proteins may target
A) Protein kinases
B) Adenylate cyclase
C) Ion channels
D) all of the above
E) A and C
Answer: D
Although the extracellular environment has a high sodium ion
concentration and the intracellular environment has a high potassium
ion concentration, both must be neutralized by negatively charged
molecules. In the extracellular case, what is the principal anion?
A) PO4-
B) OH-
C) Cl-
D) HCO3-
Answer: C
True or False
1) Generally, the total number of nonpolar amino acids has a greater
effect on protein structure than the exact order of amino acids in the
polypeptide chain
2) The 'polypeptide backbone" refers to all atoms in a
polypeptide chain, except for those that form the peptide bonds
3) The chemical properties of amino acid side chains include
charged, uncharged, polar and nonpolar
4) The relative distribution of polar and nonpolar amino acids in a
folded protein is determined largely by hydrophobic interactions,
which favor clustering of nonpolar side chains in the interior
Answer:
1) False
2) False
3) True
4) True
A-kinase
A) adds phosphates to target proteins
B) creates cAMP
C) adds phosphates to G-proteins
D) is a seven pass membrane receptor
Answer: A
Endosymbiotic theory suggests that
A) The nucleus is derived from an ancestral prokaryote
B) Mitochondria are derived from an ancestral prokaryote
C) The chloroplast is derived from an ancestral prokaryote
D) B and C
E) A and B
Answer D
Cells use membranes to help maintain set ranges of ion concentrations
inside and outside the cell. Which of the following ions is the most
abundant inside a typical mammalian cell?
A) K+
B) Na+
C) Cl-
D) Ca2+
Answer: A
You have started two yeast cultures; culture A is growing in low
oxygen, culture B is growing in high oxygen
1) Which of the yeast cultures should grow faster?
2) Which of the yeast culture should produce the most ethanol?
3) Which culture produces the most CO2?
Answer:
1) B
2) A
3) A
MATCH
Sugar --------> _____________________ Proteins
Fatty acid----->_____________________ Nucleic Acids
Amino acid--->_____________________ Polysaccharides
Nucelic acid-->_____________________ Lipids
Answer:
Polysaccharides
Lipids
Proteins
Nucleic Acids
Enzyme-linked receptors
A) Often autophosphorylate
B) Often are associated with growth regulation
C) Are considered a tyrosine kinase
D) all of the above
Answer: D
Polar or Nonpolar?
Water
Glucose
Fatty Acid
DNA
Leucine
Glutamine
Cholesterol
Glycogen
Sucrose
Testosterone
Answer:
Water - Polar
Glucose - Polar
Fatty acid - NONpolar
DNA - Polar
Leucine - NONpolar
Glutamine - Polar
Cholesterol - NONpolar
Glycogen - Polar
Sucrose - Polar
Testosterone - NONpolar
Classify each base as either a pyrimidine or a purine
Adenine
Guanine
Cytosine
Uracil
Thymine
Answer
A - Purine
G - Purine
C - Pyrimidine
U - Pyrimidine
T - Pyrimidine
True or false
Increase in cytoplasmic Ca2+ bby IP3 is the result of a ligand gated transporter
Answer: True
Polypeptides are synthesized from amino acid building blocks. The
condensation reaction between the growing polypeptide chain and the
next amino acid to be added involves the loss of ___________.
A) A water molecule
B) a carbon atom
C) a carboxylic acid group
D) an amino group
Answer: A