©SOPHIABENNET@2024/2025 Wednesday, August 21, 2024 12:13 PM
NAU BIO 344 Posner Final Exam
Practice Questions and Answers
In a polarized cell, a barrier is created by a specific type of
intercellular junction that maintains the separation of membrane
proteins and between the apical and the basal sides of the cell. This
barrier is called a: - Answer✔️✔️-tight junction
What secondary structure found in proteins is often used to enable
it to cross a membrane? - Answer✔️✔️-alpha helices
An inhibitory acetylcholine receptor would - Answer✔️✔️-be a K+
channel
The nonpolar part of a phospholipids consists of - Answer✔️✔️-fatty
acid chains
Which of the following is true concerning passive transport and
active transport: - Answer✔️✔️-passive transport transfers molecules
down an electrochemical gradient while active transport transfers
molecules against an electrochemical gradient
An example of an amphiphilic phosphoglyceride is: - Answer✔️✔️-
phosphatidlyserine
Reactions that add a phosphate to specific sites on proteins in an
ATP dependent manner are important in cell signaling. The type of
enzyme that catalyzes this reaction is: - Answer✔️✔️-a protein kinase
1
, ©SOPHIABENNET@2024/2025 Wednesday, August 21, 2024 12:13 PM
In a depolarized membrane, repolarization of the neural membrane
would occur as a result of: - Answer✔️✔️-opening of K+ channels
How does an action potential travel down an axon? - Answer✔️✔️-
voltage gated Na+ channels go from closed to open to inactivated in
an orchestrated sequential manner
In the presynaptic nerve cell, opening of voltage gated Ca+2
channels at the nerve terminal leads to: - Answer✔️✔️-exocytosis of
the contents of secretory vesicles into the synaptic cleft
The Na+-K+ pump requires ______ molecule(s) of ATP to transport
______ Na+ ions out of the cell and _______ K+ ions into the cell. -
Answer✔️✔️-1, 3, 2
Phospholipase C and Phospholipase A1 differs differ - Answer✔️✔️-in
the specific site where they cleave phospholipids
Which of the following are used to transport K+ ions against their
electrochemical gradient? - Answer✔️✔️-the sodium potassium pump
Why is it that in a resting neuron with K+ leak channels open, there
are different concentrations of K+ ions on the two sides of the
plasma membrane? - Answer✔️✔️-the membrane potential of a cell is
negative and thus the equilibrium concentration of positively
charged K+ ions is higher inside than outside the cell.
Phosphatidylinositol 3-Kinase (also known as PI3K) is a lipid
kinase. The 3 is letting you know that: - Answer✔️✔️-it catalyzes the
addition of a phosphate to the 3 position of the inositol ring.
2
, ©SOPHIABENNET@2024/2025 Wednesday, August 21, 2024 12:13 PM
A glycolipid that is part of the plasma membrane will be found: -
Answer✔️✔️-only on the side of the bilayer that faces away from the
cell (towards the extracellular fluid)
When transporting a negatively charged ion through a ligand gated
ion channel across the plasma membrane, which of the following is
True? - Answer✔️✔️-the direction of transport is determined by both
the concentration gradient and the membrane potential
Both lipid and protein molecules can diffuse in the plane of a
membrane. This is referred to as: - Answer✔️✔️-Lateral diffusion
The forces that hold together the lipids in the membranes that
surround organelles are: - Answer✔️✔️-Non-Covalent interactions
A prokaryotic organism is isolated from a hydrothermal vent in
Yellowstone national park where despite the fact that the
temperature is extremely high, it has been thriving. In the plasma
membrane of such an organism, which of the following concerning
its phospholipid composition will help it adapt to the high
temperature of its environment? - Answer✔️✔️-a predominance of
long chain saturated fatty acids
The reason that an action potentials cannot move backward is: -
Answer✔️✔️-voltage gated sodium ion channels cannot go directly
from the inactive state to open
The sodium potassium pump is a - Answer✔️✔️-P-type ATPase
3
NAU BIO 344 Posner Final Exam
Practice Questions and Answers
In a polarized cell, a barrier is created by a specific type of
intercellular junction that maintains the separation of membrane
proteins and between the apical and the basal sides of the cell. This
barrier is called a: - Answer✔️✔️-tight junction
What secondary structure found in proteins is often used to enable
it to cross a membrane? - Answer✔️✔️-alpha helices
An inhibitory acetylcholine receptor would - Answer✔️✔️-be a K+
channel
The nonpolar part of a phospholipids consists of - Answer✔️✔️-fatty
acid chains
Which of the following is true concerning passive transport and
active transport: - Answer✔️✔️-passive transport transfers molecules
down an electrochemical gradient while active transport transfers
molecules against an electrochemical gradient
An example of an amphiphilic phosphoglyceride is: - Answer✔️✔️-
phosphatidlyserine
Reactions that add a phosphate to specific sites on proteins in an
ATP dependent manner are important in cell signaling. The type of
enzyme that catalyzes this reaction is: - Answer✔️✔️-a protein kinase
1
, ©SOPHIABENNET@2024/2025 Wednesday, August 21, 2024 12:13 PM
In a depolarized membrane, repolarization of the neural membrane
would occur as a result of: - Answer✔️✔️-opening of K+ channels
How does an action potential travel down an axon? - Answer✔️✔️-
voltage gated Na+ channels go from closed to open to inactivated in
an orchestrated sequential manner
In the presynaptic nerve cell, opening of voltage gated Ca+2
channels at the nerve terminal leads to: - Answer✔️✔️-exocytosis of
the contents of secretory vesicles into the synaptic cleft
The Na+-K+ pump requires ______ molecule(s) of ATP to transport
______ Na+ ions out of the cell and _______ K+ ions into the cell. -
Answer✔️✔️-1, 3, 2
Phospholipase C and Phospholipase A1 differs differ - Answer✔️✔️-in
the specific site where they cleave phospholipids
Which of the following are used to transport K+ ions against their
electrochemical gradient? - Answer✔️✔️-the sodium potassium pump
Why is it that in a resting neuron with K+ leak channels open, there
are different concentrations of K+ ions on the two sides of the
plasma membrane? - Answer✔️✔️-the membrane potential of a cell is
negative and thus the equilibrium concentration of positively
charged K+ ions is higher inside than outside the cell.
Phosphatidylinositol 3-Kinase (also known as PI3K) is a lipid
kinase. The 3 is letting you know that: - Answer✔️✔️-it catalyzes the
addition of a phosphate to the 3 position of the inositol ring.
2
, ©SOPHIABENNET@2024/2025 Wednesday, August 21, 2024 12:13 PM
A glycolipid that is part of the plasma membrane will be found: -
Answer✔️✔️-only on the side of the bilayer that faces away from the
cell (towards the extracellular fluid)
When transporting a negatively charged ion through a ligand gated
ion channel across the plasma membrane, which of the following is
True? - Answer✔️✔️-the direction of transport is determined by both
the concentration gradient and the membrane potential
Both lipid and protein molecules can diffuse in the plane of a
membrane. This is referred to as: - Answer✔️✔️-Lateral diffusion
The forces that hold together the lipids in the membranes that
surround organelles are: - Answer✔️✔️-Non-Covalent interactions
A prokaryotic organism is isolated from a hydrothermal vent in
Yellowstone national park where despite the fact that the
temperature is extremely high, it has been thriving. In the plasma
membrane of such an organism, which of the following concerning
its phospholipid composition will help it adapt to the high
temperature of its environment? - Answer✔️✔️-a predominance of
long chain saturated fatty acids
The reason that an action potentials cannot move backward is: -
Answer✔️✔️-voltage gated sodium ion channels cannot go directly
from the inactive state to open
The sodium potassium pump is a - Answer✔️✔️-P-type ATPase
3
