BS 161 EXAM 2 NEWEST EXAM COMPLETE 200 QUESTIONS AND
CORRECT DETAILED ANSWERS (VERIFIED ANSWERS) |ALREADY
GRADED A+
Which of the following is least likely to cross a lipid bilayer with no proteins?
a steroid hormone such as testosterone
CO2
H2O
ATP
O2 - correct answer ATP
Which one of the following describes the hydrophilic component of cholesterol?
a phosphate group only
a hydroxyl group only
a single hydrocarbon tail
a phosphate group and a chemical group called choline
a group of four planar rings and a hydroxyl group - correct answer a hydroxyl group only
For translation to occur in eukaryotes, mRNA molecules must be transported through which
membrane(s)?
nuclear envelope (inner and outer nuclear membranes)
mitochondrial membrane (inner and outer)
,plasma membrane
endoplasmic reticulum membrane
ribosome membrane - correct answer
In intestinal epithelial cells, a transport protein moves glucose into the cytoplasm against its
concentration gradient at the same time that it transports Na+ into the cell down its
electrochemical gradient. Which of the following CORRECTLY describes this cotransport of
glucose and sodium?
Energy from ATP directly drives the movement of glucose
No energy source is required for glucose to move against its concentration gradient
Na+ can move by simple diffusion, but glucose transport requires a carrier protein
The Na+ concentration gradient provides the energy for glucose transport - correct answer The
Na+ concentration gradient provides the energy for glucose transport
The lipid components of cellular membranes often include:
fatty acids and cholesterol.
phospholipids and fatty acids.
phospholipids and cholesterol.
phospholipids - correct answer phospholipids and cholesterol.
, In response to seasonal changes in temperature, many organisms must alter the composition of
their plasma membranes to maintain the proper degree of fluidity. As summer turns to fall and
eventually into winter, which of the following would you predict you would observe in the
plasma membranes of organisms that are unable to regulate their body temperature?
a decrease in phospholipid fatty acid side chain length and an increase in side chain saturation
an increase in phospholipid fatty acid side chain length and an increase in side chain saturation
a decrease in phospholipid fatty acid side chain length and a decrease in side chain saturation
an increase in phospholipid fatty acid side chain length and a decrease in side chain saturation -
correct answer a decrease in phospholipid fatty acid side chain length and a decrease in side
chain saturation
Which component of a phospholipid is found in the interior of a lipid bilayer?
fatty acids
glycerol
phosphate group - correct answer fatty acids
Suppose you are studying the transport of a certain polar molecule across the plasma
membrane of cells in culture. Over a period of time, you measure the concentration of a polar
molecule inside and outside of the cells. You find that the concentration of the molecule is
lower in the cell but is gradually increasing. You also measure the ATP concentration inside the
cell and find that it is not changing. Which of the following is probably responsible for the
transport of this polar substance into the cell?
endocytosis
simple diffusion
CORRECT DETAILED ANSWERS (VERIFIED ANSWERS) |ALREADY
GRADED A+
Which of the following is least likely to cross a lipid bilayer with no proteins?
a steroid hormone such as testosterone
CO2
H2O
ATP
O2 - correct answer ATP
Which one of the following describes the hydrophilic component of cholesterol?
a phosphate group only
a hydroxyl group only
a single hydrocarbon tail
a phosphate group and a chemical group called choline
a group of four planar rings and a hydroxyl group - correct answer a hydroxyl group only
For translation to occur in eukaryotes, mRNA molecules must be transported through which
membrane(s)?
nuclear envelope (inner and outer nuclear membranes)
mitochondrial membrane (inner and outer)
,plasma membrane
endoplasmic reticulum membrane
ribosome membrane - correct answer
In intestinal epithelial cells, a transport protein moves glucose into the cytoplasm against its
concentration gradient at the same time that it transports Na+ into the cell down its
electrochemical gradient. Which of the following CORRECTLY describes this cotransport of
glucose and sodium?
Energy from ATP directly drives the movement of glucose
No energy source is required for glucose to move against its concentration gradient
Na+ can move by simple diffusion, but glucose transport requires a carrier protein
The Na+ concentration gradient provides the energy for glucose transport - correct answer The
Na+ concentration gradient provides the energy for glucose transport
The lipid components of cellular membranes often include:
fatty acids and cholesterol.
phospholipids and fatty acids.
phospholipids and cholesterol.
phospholipids - correct answer phospholipids and cholesterol.
, In response to seasonal changes in temperature, many organisms must alter the composition of
their plasma membranes to maintain the proper degree of fluidity. As summer turns to fall and
eventually into winter, which of the following would you predict you would observe in the
plasma membranes of organisms that are unable to regulate their body temperature?
a decrease in phospholipid fatty acid side chain length and an increase in side chain saturation
an increase in phospholipid fatty acid side chain length and an increase in side chain saturation
a decrease in phospholipid fatty acid side chain length and a decrease in side chain saturation
an increase in phospholipid fatty acid side chain length and a decrease in side chain saturation -
correct answer a decrease in phospholipid fatty acid side chain length and a decrease in side
chain saturation
Which component of a phospholipid is found in the interior of a lipid bilayer?
fatty acids
glycerol
phosphate group - correct answer fatty acids
Suppose you are studying the transport of a certain polar molecule across the plasma
membrane of cells in culture. Over a period of time, you measure the concentration of a polar
molecule inside and outside of the cells. You find that the concentration of the molecule is
lower in the cell but is gradually increasing. You also measure the ATP concentration inside the
cell and find that it is not changing. Which of the following is probably responsible for the
transport of this polar substance into the cell?
endocytosis
simple diffusion
