Membranes are fluid mosaics of what major components?

• Proteins, cholesterol, and sugar

• Phospholipids, proteins, and cholesterol

• Phospholipids, nucleic acids, and cholesterol

• Glucose, proteins, and phospholipids

The fluid mosaic model of the membrane proposed that membranes:

• Consist of a single layer of phospholipids and proteins

• Consist of a phospholipid bilayer composed of a variety of fatty acids

• Consist of protein molecules embedded in a dynamic bilayer of phospholipids

• Consist of a phospholipid bilater between two layers of hydrophilic proteins

Which of the following is NOT a function of membrane proteins?

• Transducing signals from the environment into the cell

• Synthesizing proteins

• Anchoring the cell cytoskeleton and extracellular matrix

• Marking cells for recognition

Which of the following statements about diffusion is true?

• It's a process where water moves across a semi-permeable barrier to a region of high solute concentration

• It requires an expenditure of energy by the cell

• It's a process where molecules move from a region of lower concentration to a region of higher concentration

• It's a process where molecules move from a region of higher concentration to a region of lower concentration

Which molecule most easily diffuses across a biological membrane's lipid bilayer, without help of a protein?

• H2O (water)

• O2 (molecular oxygen)

• H2PO4-

• Glucose

• Na+

What type of molecule transport is also called the process of "cell eating"?

• Phagocytosis

• Receptor-mediated Endocytosis

• Exocytosis

• Pinocytosis

• Facilitated diffusion

Passive membrane transport processes include ______.

• Consumption of ATP for energy.

• The use of transport proteins to move a substance from high to low concentration.

• Movement of a substance with (down) its concentration gradient.

• Movement of a substance up (against) its concentration gradient.

What is the difference between active and passive transport across a membrane?

• Both active and passive transport move substances down their concentration gradients.

• Active transport is ATP dependent. Passive transport does not require energy.

• Active transport requires cell to cell communication. Passive transport does not require cell communication.

• Active transport can be performed without transport proteins while passive transport cannot.

Osmosis is best defined as the movement of:

• Water molecules across a semi-permeable membrane into a region of low solute concentration.

• Solute molecules from an area of high concentration to an area of lower concentration.

• Water molecules across a semi-permeable membrane into a region of high solute concentration.

• Water molecules inside a cell that can't be transported out.

• Solute molecules from an area of low concentration to an area of higher concentration.

Plants become turgid when placed in this type of solution:

• Hypotonic

• Isotonic

• Hypertonic

• Megatonic