Membrane Structure and Function
either direction
Passive transport permits the solute to move in ________.
turgor pressure
A cell placed in a hypotonic solution would exude a high _________.
Endocytosis
A nursing infant is able to obtain disease-fighting antibodies, which are large protein molecules, from its mother's milk. These molecules probably enter the cells lining the baby's digestive tract via which process?
membrane potential; electrogenic pumps
All cells have voltages across their membranes. This voltage is called a(n) __________ and is often maintained by __________.
B; the diffusion gradient in cell B is steeper
Cells A and B are the same size, shape, and temperature, but cell A is metabolically less active than cell B; cell B is actively converting oxygen to water in cellular respiration. Oxygen will diffuse more rapidly into cell __________ because __________.
channel
In facilitated diffusion, __________ proteins provide openings in the plasma membrane for substances to flow through without changing structure
the concentration gradient of the molecule
Net movement of the population of solute molecules occurs down ________.
into the cell
The sodium-potassium pump transports sodium ions out of the cell and transports potassium ions __________.
Cell-to-cell recognition
What function do carbohydrates fulfill in the plasma membrane?
These proteins exhibit both hydrophilic and hydrophobic properties.
Which of the following is correct regarding integral proteins?
Facilitated diffusion of solutes may occur through channel or transport proteins in the membrane.
Which of these statements describes some aspect of facilitated diffusion?
Because it moves solutes against their concentration gradient
Why is energy required for active transport?
Carrier
__________ proteins allow passage of substances through the plasma membrane after undergoing a subtle change in shape.
the surface of the plasma membrane
Where are peripheral proteins found?
It is a passive process.
Which of the following statements about diffusion is true?