Understanding the Plasma Membrane and Transport Mechanisms

What is the primary function of the plasma membrane?

• To control what enters and leaves the cell

• To produce proteins

• To store genetic information

• To provide energy to the cell

Which part of a phospholipid is hydrophilic?

• The phosphate head

• The entire molecule

• The fatty acid tails

• The glycerol backbone

What role do glycoproteins play in the cell membrane?

• They act as energy sources

• They provide structural support

• They transport water

• They serve as identification tags

What is the role of cholesterol in animal cell membranes?

• To synthesize lipids

• To transport proteins

• To stabilize the membrane

• To provide energy

How does the cell membrane contribute to homeostasis?

• By producing hormones

• By controlling the movement of substances

• By storing nutrients

• By generating electrical signals

What is facilitated diffusion?

• Active transport of ions

• Diffusion of water across a membrane

• Diffusion of molecules through a membrane with the help of carrier proteins

• Movement of molecules against the concentration gradient

What is active transport?

• Movement of molecules from high to low concentration

• Diffusion of water across a membrane

• Movement of molecules from low to high concentration requiring energy

• Passive movement of ions

What is the main difference between diffusion and osmosis?

• Diffusion involves water, osmosis does not

• Osmosis involves water, diffusion does not

• Diffusion requires energy, osmosis does not

• Osmosis requires energy, diffusion does not

In a hypertonic solution, what happens to a cell?

• It swells

• It remains the same

• It shrinks

• It bursts

Which type of solution causes no net movement of water into or out of a cell?

• Hypertonic

• Isotonic

• Hypotonic

• Supersaturated