chp 6 quiz Flashcards
(92 cards)
Proteins that extend from the cytoskeleton within the cell, through the plasma membrane, and into the extracellular matrix are ________.
integrin proteins
Which of the following types of transport does not require membrane proteins?
simple diffusion
A membrane that allows only certain molecules to pass through it is called ________.
selectively permeable
active transport_______
utilizes energy
the rate of diffusion is influence by______
the concentration gradient, membrane permeability, membrane surface area
hydrophobic molecules usually enter a cell via
diffusion
A six molar sucrose (molecular weight = 342g) solution would contain ________.
2052g sucrose per liter
Ion channels that can be opened by physiological stimuli are said to be ________.
gated
The transport of amino acids across epithelial membranes requires the ________.
Na+/H+pump
Where are GLUT carriers located in an unstimulated muscle fiber?
within the cytoplasmic vesicles
Glucose transported via the GLUT carrier is characterized as ________.
passive transport
Active transport carriers are also called ________.
pumps
Hyperkalemia would ________ the resting membrane potential of the cell.
decrease
If the intracellular concentration of Ca2+ was 10mEq/L and the extracellular concentration was 150mEq/L, the Ca2+ equilibrium potential would be ________.
+35.9mV
If the Na+/K+ pump did not function, the ________ of the cell would become more ________.
interior; positively-charged
The sodium equilibrium potential using an extracellular Na+ concentration of 145 mEq/L and an intracellular concentration of 14 mEq/L would be approximately ________.
+62mV
Which of the following is NOT a general category of cell signaling molecules?
enzymatic signaling
Regardless of solubility, a cell signaling molecule could not affect a target cell without ________.
specific receptor proteins within the cell or in the plasma membrane
Where is the G-protein complex when a regulatory molecule is not bound to its receptor?
The three subunits are together AND attached to the inner surface of the receptor.
What determines how a regulatory molecule influences its target cell?
polarity, solubility, presence of receptor proteins for the regulatory molecule
Active transport requires______
both ATP and a carrier protein
the binding of ATP to the carrier protein causes______
the carrier to change its shape
The movement of substances across the plasma membrane will continue until the ATP is used up
true