Exam 2 Flashcards
Learn the hell out of these
The region labeled “A” in the cartoon above
represents:
a. the protein component of a phospholipid
b. the cholesterol component of a phospholipid
c. the hydrophilic (polar) head group of a
phospholipid
d.the hydrophobic (nonpolar) head group of a
phospholipid
e.the hydrophobic (nonpolar) fatty acid tail of a
phospholipid
c.the hydrophilic (polar) head group of a
phospholipid
he region labeled “B” in the cartoon above
represents:
a. the protein component of a phospholipid
b. the cholesterol component of a phospholipid
c. the hydrophilic (polar) head group of a
phospholipid
d.the hydrophobic (nonpolar) head group of a
phospholipid
e.the hydrophobic (nonpolar) fatty acid tail of a
phospholipid
e.the hydrophobic (nonpolar) fatty acid tail of a
phospholipid
When phospholipids are placed in an aqueous
environment, they assemble into membranes. Which
of the following is true about a membrane?
a. It contains two layers of phospholipids with the
“B” regions facing the inside and the “A”
regions facing out.
b.It contains two layers of phospholipids with the
“A” regions facing the inside and the “B” regions facing out.
c. It contains a single layer of phospholipids with
the “B” region facing the inside and the A”
region facing out.
d. It contains a single layer of phosopholipids with
the “A” region facing the inside and the “B”
region facing out.
a. It contains two layers of phospholipids with the
“B” regions facing the inside and the “A”
regions facing out.
Why don’t Na+ ions move across the plasma membrane and down their concentration gradient all the time?
a. The plasma membrane is not permeable to Na+ ions.
b. The Na+/K+ pump is required and it only operates when ATP is plentiful.
c. A Na+ channel is required and it is usually closed.
d. A & C.
e. A, B, & C.
d. A & C.
The plasma membrane is not permeable to Na+ ions.
A Na+ channel is required and it is usually closed.
Which of the following is NOT TRUE about Na+ ion
channels?
a. They are proteins.
b. They are embedded in the plasma membrane.
c. They allow Na+ ions to move down their
concentration gradient.
d. They require energy in order to move Na+ ions.
e. They undergo a conformational change to open
or close.
d. They require energy in order to move Na+ ions.
Which of the following is NOT TRUE about the
Na+/K+ pump?
a. It is a protein.
b. It moves Na+ ions against their concentration
gradient.
c.The hydrolysis of ATP results in the Na+/K+
pump changing what side of the plasma
membrane it is open to.
d. The hydrolysis of ATP results in the Na/K+
pump changing its affinity for Na+ ions.
e.The pump has a high affinity for Na+ ions when
it is open to the outside of the cell.
e.The pump has a high affinity for Na+ ions when
it is open to the outside of the cell.
Which of the following is NOT an organelle with a membrane?
a. nucleus
b. rough endoplasmic reticulum
c. smooth endoplasmic reticulum
d. ribosome
e. Golgi
d. ribosome
Which of the following is present in plant cells, but
not animal cells?
a. plasma membrane
b. cell wall
c. Golgi
d. A&B
e. B&C
b.cell wall
Glucose is in lower concentration inside the fat cell
than outside. This is…
a. A concentration gradient
b. Facilitated diffusion
c. Activation energy
d. Impossible
a. A concentration gradient
Under these conditions, glucose would enter the fat
cell through the transporter by…
a. Diffusion
b. Facilitated diffusion
c. Active transport
d. Endocytosis
e. Exocytosis
b.Facilitated diffusion
Which of the following is TRUE about the synthesis
of the insulin protein?
a.Insulin is synthesized by ribosomes floating free
in the cytoplasm.
b.Insulin is synthesized by ribosomes attached to
the rough ER.
c.Insulinis synthesized by ribosomes attached to
the smooth ER.
d.Insulin is synthesized by ribosomes attached to
the Golgi.
b.Insulin is synthesized by ribosomes attached to
the rough ER.
The insulin protein goes through the secretory pathway in the B-islet cells, but is not immediately secreted out of the cell. Instead, the protein is packaged in a vesicle that waits in the cytoplasm for a signal that insulin is needed in the blood. When that signal arrives, the vesicle fuses with the plasma membrane, thereby releasing insulin out of the cell.
This vesicle fusion is an example of:
a. sorting
b. endocytosis
c. exocytosis
d. diffusione.
e. facilitated diffusion
c.exocytosis
If insulin has not folded into its proper conformation,
it cannot bind to the insulin receptors. A protein’s
conformation (or functional shape) refers to its:
a. primary structure
b. secondary structure
c. tertiary structure
d. quaternary structure
c.tertiary structure
Insulin is made up of two alpha helixes, which are
examples of _____.
a. primary structure
b. secondary structure
c. tertiary structure
d. quaternary structure
b.secondary structure
A
What type of interactions would serine most
likely participate in?
a. van der Waal’s interactions
b. ionic bonds
c. covalent bonds
d. hydrogen bonds
d.hydrogen bonds
When glucose enters the cells it enters glycolysis.
Which of the following is NOT true about glycolysis?
a. it occurs in the cytoplasm.
b. It occurs under both anaerobic and aerobic
conditions.
c.It makes a few ATP molecules by oxidative
phosphorylation.
d.It completely oxidizes the carbons in glucose to
carbon dioxide.
e.C & D
c.It makes a few ATP molecules by oxidative
phosphorylation.
d.It completely oxidizes the carbons in glucose to
carbon dioxide.
The first reaction in glycolysis is catalyzed by the enzyme hexokinase and it converts the substrates glucose and ATP to glucose-6-phosphate and ADP. The reaction is shownbelow.
glucose + ATP ↔ glucose-6-phosphate + ADP
This reaction is part of the _________ phase of
glycolysis.
a. energy investment
b. cleavage
c. energy release
d. reduction
e. oxidation
a.energy investment
The first reaction in glycolysis is catalyzed by the enzyme hexokinase and it converts the substrates glucose and ATP to glucose-6-phosphate and ADP. The reaction is shownbelow.
glucose + ATP ↔ glucose-6-phosphate + ADP
Which of the following is NOT TRUE about
hexokinase?
a. it speeds up the reaction.
b. It is not consumed in the reaction.
c. It lowers the activation energy of the reaction.
d. It lowers the G of the reaction.
d.It lowers the G of the reaction.
What conclusions about the NE transporter can be drawn from the graph above?
a. The NE transporter normally increases sensitivity to cocaine.
b. The NE transporter normally decreases sensitivity to cocaine.
c. The NE transporter has no affect on sensitivity to cocaine.
a.The NE transporter normally increases sensitivity to cocaine.
