A set of erythrocytes is placed in a beaker of 0.9% NaCl.Nothing appears to happen to the cells. Why?
0.9% NaCl is hypertonic to the cells.
Sodium blocks the movement of water.
0.9% NaCl is hypotonic to the cells.
0.9% NaCl is iostonic to the cells.
water has not moved at all.
Question 2
Select one answer.
Which substance would be mostlikely to pass through a lipid bilayer/plasma membrane withoutembedded proteins?
water
a steroid hormone
a large fatty acid
a large peptide hormone
a sodium ion
Question 3
Select all that apply.
Which of the following can cross the cellâs plasmamembrane without the assistance of protein transporters?Select all that apply.
large polar molecules
positively charged ions
small hydrophobic molecules
gasses
Question 4
Select one answer.
Biological Membranesare:
symmetrical.
impermeable.
static.
dynamic.
Question 5
Select one answer.
How does the selectivepermeability of the membrane help the cell.
This allows the cell to maintain the proper shape.
This allows the cell to regulate what enters and exits
This allows the cell to maintain a constant temperature.
All of these
Question 6
Select one answer.
What is the role of carbohydratesin the plasma membrane?
cellular identification
adhesion
transport materials across the membrane
help maintain fluidity
Question 7
Select one answer.
Which component of the plasmamembrane has the widest variety of functions?
sterols
carbohydrates
phospholipids
proteins
Question 8
Select one answer.
All of the following have aneffect on the fluidity of a membrane except:
interactions among fatty acids in the core of the bilayer
the cholesterol content
the ratio of saturated to unsaturated fatty acids
the presence of integral proteins in the membrane
