USABO Open Exam Questions and Answers
2026 | Solved and Verified | 100% Accurate
• Which molecular motor protein is involved in the contractile ring
during cytokinesis? -✓✓Myosin.
• What is the ratio of the concentration of protonated to deprotonated
forms of an acid with a pKa of 4.76 in a pH environment of 6.8? -✓✓1 :
100.
• In oxidative phosphorylation, which chemical species is oxidized in
choice A? -✓✓H2O.
• In oxidative phosphorylation, which chemical species is reduced in
choice A? -✓✓NAD+.
• In oxidative phosphorylation, which chemical species is
phosphorylated in choice A? -✓✓ATP.
• Which scientist is incorrectly matched with their discovery regarding
transformation through bacteriophages? -✓✓Frederick Griffith.
• What is a likely amino acid sequence for a transmembrane protein
composed of alpha helices? -✓✓ALILALMWWLLF.
• True or False: Ubiquinone proteins have a heme group to facilitate
electron transport. -✓✓False.
• True or False: FADH2 adds its electrons to complex III while NADH
adds its electrons in complex I. -✓✓False.
, • True or False: Cytochrome a is more electronegative than cytochrome
b. -✓✓True.
• True or False: Cytochrome c is more electronegative than cytochrome
b. -✓✓True.
• What is the role of the ethylene receptor in plant growth? -✓✓It
mediates the plant's response to ethylene, including the triple response.
• What happens to seedlings with a loss of function mutation in the
ethylene receptor? -✓✓They may not respond to ethylene exposure.
• What does a constitutive activity in the ethylene receptor lead to? -
✓✓Activation of kinase important for the triple response.
• What is the significance of the pKa value in relation to acid-base
chemistry? -✓✓It indicates the pH at which the concentrations of
protonated and deprotonated forms are equal.
• What is the main function of Myosin in cellular processes? -✓✓It is a
molecular motor protein involved in muscle contraction and cytokinesis.
• What is the primary role of Actin in the cell? -✓✓It provides structural
support and is involved in cell movement.
• What is the function of Kinesin in the cell? -✓✓It is a motor protein
that transports cellular cargo along microtubules.
• What is the function of Dynein in the cell? -✓✓It is a motor protein
that moves cargo towards the cell's center along microtubules.
2026 | Solved and Verified | 100% Accurate
• Which molecular motor protein is involved in the contractile ring
during cytokinesis? -✓✓Myosin.
• What is the ratio of the concentration of protonated to deprotonated
forms of an acid with a pKa of 4.76 in a pH environment of 6.8? -✓✓1 :
100.
• In oxidative phosphorylation, which chemical species is oxidized in
choice A? -✓✓H2O.
• In oxidative phosphorylation, which chemical species is reduced in
choice A? -✓✓NAD+.
• In oxidative phosphorylation, which chemical species is
phosphorylated in choice A? -✓✓ATP.
• Which scientist is incorrectly matched with their discovery regarding
transformation through bacteriophages? -✓✓Frederick Griffith.
• What is a likely amino acid sequence for a transmembrane protein
composed of alpha helices? -✓✓ALILALMWWLLF.
• True or False: Ubiquinone proteins have a heme group to facilitate
electron transport. -✓✓False.
• True or False: FADH2 adds its electrons to complex III while NADH
adds its electrons in complex I. -✓✓False.
, • True or False: Cytochrome a is more electronegative than cytochrome
b. -✓✓True.
• True or False: Cytochrome c is more electronegative than cytochrome
b. -✓✓True.
• What is the role of the ethylene receptor in plant growth? -✓✓It
mediates the plant's response to ethylene, including the triple response.
• What happens to seedlings with a loss of function mutation in the
ethylene receptor? -✓✓They may not respond to ethylene exposure.
• What does a constitutive activity in the ethylene receptor lead to? -
✓✓Activation of kinase important for the triple response.
• What is the significance of the pKa value in relation to acid-base
chemistry? -✓✓It indicates the pH at which the concentrations of
protonated and deprotonated forms are equal.
• What is the main function of Myosin in cellular processes? -✓✓It is a
molecular motor protein involved in muscle contraction and cytokinesis.
• What is the primary role of Actin in the cell? -✓✓It provides structural
support and is involved in cell movement.
• What is the function of Kinesin in the cell? -✓✓It is a motor protein
that transports cellular cargo along microtubules.
• What is the function of Dynein in the cell? -✓✓It is a motor protein
that moves cargo towards the cell's center along microtubules.
