Cells and Their Environment Quiz

In the cell membrane, ion channels serve as

• Food molecules

• Cell identifiers

• Information receivers

• Passageways

The diffusion of water through a selectively permeable membrane is called

• Exocytosis

• Osmosis

• Active transport

• Endocytosis

Which of the following is NOT a characteristic of active transport?

• It moves substances against a concentration gradient

• It requires energy from the cell

• It involves facilitated diffusion

• It relies on carrier proteins that often function as pumps

Diffusion is the movement of a substance

• Through only a lipid bilayer

• From an area of low concentration to an area of higher concentration

• Only in liquids

• From an area of high concentration to an area of lower concentration

Which type of membrane protein transmits information into the cell by responding to signal molecules?

• Carrier protein

• Receptor protein

• Marker protein

• None of the above

An ion channel is a transport protein that

• Moves substances against a concentration gradient

• Pumps ions only out of a cell

• Allows ions to move across the cell membrane so that the ions do not come in contact with the nonpolar interior of the lipid bilayer

• Has pores that are always open

When particles move out of a cell through facilitated diffusion, the cell

• Gains energy

• Uses energy

• First gains and then uses energy

• Does not use energy

The sodium-potassium pump

• Helps cells maintain homeostasis

• Carries ions across the membrane from an area of high concentration to an area of lower concentration

• Helps maintain sodium ion gradient

• Helps maintain sodium ion gradient and maintain homeostasis

Tags

NGSS.HS-LS1-3

Molecules that are too large to be moved through the cell membrane can be transported into the cell by

• Osmosis

• Endocytosis

• Exocytosis

• Diffusion

Which of the following occurs when a signal molecule binds to a receptor protein on a cell's surface?

• The receptor can open an ion channel in the cell membrane

• The receptor can act as an enzyme, causing chemical changes in the cytoplasm

• The receptor can cause the formation of a second messenger

• All of the choices are correct