Exam 3: The Plasma Membrane and Membrane Potential

Integrins

Which of the following is not part of the extracellular matrix?

Opening a sodium channel during the resting potential would cause sodium ions to move along an electrical gradient and along a concentration gradient.

If an electrical gradient is present for a given substance, the substance may be able to get through the membrane without going through a carrier or channel.

Use the figure above to answer the corresponding questions.Assume the membrane is always permeable to water. -In beaker 1, the solution on the right side of the membrane a.has a lower osmolarity than the solution on the left side of the membrane b.will gain water from the solution on the left side of the membrane c.has a higher osmotic pressure than the solution on the left side of the membrane d.has a lower osmolarity than the solution on the left side of the membrane and will gain water from the solution on the left side of the membrane e.will gain water from the solution on the left side of the membrane and has a higher osmotic pressure than the solution on the left side of the membrane

Connexons are carbohydrate building blocks of gap junctions that allow ions to pass from the cytosol of one cell into the cytosol of an adjacent cell.

Glucose moves against its concentration gradient through the cell membrane by passing through carriers that simultaneously transport ____________________ ions.

A common antiporter transports ____________________ ions out of the cell while it transports ____________________ ions into the cell.

Use the figure above to answer the corresponding questions. -In this figure, the carrier is a.transporting Na+ ions into the ECF b.transporting K+ ions into the ICF c.about to become phosphorylated. d.performing secondary active transport e.transporting K+ ions into the ICF and performing secondary active transport

Which extracellular fiber does not develop properly in scurvy?

Indicate whether the force in question tends to move the involved ion into or out of the cell by filling in the blank using the following code. a.tends to move the ion into the cell b.tends to move out of the cell -Na⁺-K⁺ pump for Na⁺

The rate of carrier-mediated transport is limited by

The primary barrier to passage of water-soluble substances across the plasma membrane is the outer layer of carbohydrates.

Exocytosis involves expelling a substance when the plasma membrane unites with a special carrier protein.

Match the term to the correct description. a.collagen b.elastin c.fibronectin d.keratin -Important in cell aggregation to form tissues

Some carrier molecules do not require energy to accomplish transport of a substance across the membrane.

Scurvy is the result of a vitamin ____________________ deficiency and results in abnormal formation of the protein called ____________________.

Use the figure above to answer the corresponding questions. -Describe the effects of the concentration and electrical gradients on the movement of Na⁺ and K⁺ ions through the membrane.

Most gases and small ions are highly soluble in lipids and can, therefore, pass easily between phospholipid molecules in the plasma membrane.

The surface carbohydrates within the plasma membrane serve as cell adhesion molecules (CAMs), which cells use to grip hold of one another and to surrounding connective-tissue fibers.