AP Biology Cells

According to the fluid mosaic model of cell membranes, phospholipids___________________.

• can shift laterally along the plane of the membranee

• frequently flip-flop from one side of the membrane to the other

• occur in an uninterrupted bilayer, with membrane proteins restricted to the surface of the membrane

• have hydrophilic tails in the interior of the membrane

Which of the following types of molecules are hydrophilic and therefore excluded from the hydrophobic portion of the phospholipid bilayer?

• transmembrane proteins

• integral membrane proteins

• peripheral proteins

• cholesterol

In what way do the membranes of a eukaryotic cell vary?

• Phospholipids are found only in certain membranes

• Certain proteins are unique to each membrane

• Only certain membranes of the cell are selectively permeable

• Some membranes have hydrophobic surfaces exposed to the cytoplasm while others have hydrophilic surfaces facing the cytoplasm.

Which of the following processes is an "umbrella" term for the others?

• Osmosis.

• Facilitated diffusion.

• Passive transport.

• Transport of an ion down its electrochemical gradient.

Which of the following membrane activities requires energy from ATP?

• Facilitated diffusion of chloride ions through a chloride channel.

• Movement of Na⁺ ions from lower concentration in a mammalian cell to a higher concentration in the extracellular fluid.

• Movement of glucose molecules into a bacteria cell from a medium containing a higher concentration of glucose than inside the cell.

• Movement of carbon dioxide out of a paramecium.

An animal cell lacking in carbohydrates on the external surface of its plasma membrane would likely be impaired in which function?

• transporting ions against an electrochemical gradient

• cell-cell recognition

• attaching the plasma membrane to the cytoskeleton

• establishing a diffusion barrier to charged molecules

cells contain an internal membrane system known as the ______ ____ where lipid components of the cell membrane are assembled along with proteins and other materials

• Eukaryotic, endoplasmic reticulum (ER)

• Prokaryotic, endoplasmic reticulum (ER)

• Mutant, oxygen exchanger

• New, permeable membrane

______ are the biological equivalent of a solar cell.

• Mitochondria

• Chloroplasts

• ER

• Golgi Apparatus

Tags

NGSS.HS-LS2-5

NGSS.HS-LS1-5

Most prokaryotic cells produce a strong supporting layer around the cell membrane known as a(n) ___ ____. 

• plastic cellotite

• cell wall

• selective argroleme

• vacuole pyrite

The ____ ____ gives cell membranes a flexible structure

• lipid bilayer

• lipid loped

• loped liped

• multi lingual