Unit 4: Cell Structure, Function and Transport Test

Passive transport can best be described as:

• the movement of materials across the cell membrane against a concentration gradient.
• the movement of materials across the cell membrane using cellular energy.
• the movement of materials across the cell membrane without using cellular energy.
• the movement of materials across the cell membrane using ATP.

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

• endocytosis
• protein pumps
• exocytosis
• facilitated diffusion

Aquaporins are necessary protein channels in the cell membrane required for osmosis. Why are they needed in order for water to pass through the membrane?

• The internal portion of the cell membrane is hydrophobic.
• The external portion of the cell membrane is hydrophobic.
• The internal portion of the cell membrane is hydrophilic.
• The external portion of the cell membrane is hydrophilic.

In which type of solution would a human blood cell most likely maintain homeostasis?

• isotonic
• hypertonic
• hypotonic
• lysotonic

A raw egg is placed in vinegar and the shell is removed. The egg is then placed in a solution of corn syrup. Which description below best describes what will happen to the egg?

• The corn syrup solution is hypotonic and will cause the egg to swell.
• The corn syrup solution is isotonic and will result in no change.
• The corn syrup solution is lysotonic and will cause the egg to burst.
• The corn syrup solution is hypertonic and will cause the egg to shrink.

Some particles move across the cell membrane with ease while others are not allowed to pass. This is because cell membranes are

• selectively permeable.

• impermeable.

• multicellular.

• unicellular.

Which form of cellular transport requires energy:

• osmosis
• facilitated diffusion
• diffusion
• pinocytosis

In active transport, particles:

• move from an area of high concentration to low concentration.
• move from an area of low concentration to high concentration.
• move across the cell membrane without the use of cellular energy.
• move across the cell membrane using faciliated diffusion.

Which of the following structures serves as the cell’s boundary from its environment?

• mitochondrion
• cell membrane
• chloroplast
• channel protein

The cell membrane acts as a barrier between the cell and its environment. Which best describes the type of barrier that the cell membrane forms?

• impermeable, like a brick wall
• permeable but selective, like a wall with gates
• very permeable, like a fishing net
• permeable only to water, like a very fine net