_______ regulates what enters and leaves a cell.  

• Cell Membrane
• Nucleus
• Mitochondria
• Cytoplasm

What is diffusion?

• The movement of particles from low conc. to high conc. in a given space
• The movement of particles from high conc. to low conc. in a given space

Cell membranes are described as selectively permeable.

Four students were asked to explain what this means. Which one is correct?

• Student 1: Cell membranes prevent all materials from entering the cell.

• Student 2: Cell membranes only provide structural support for the cell.

• Student 3: Cell membranes regulate which substances can enter and exit the cell.

• Student 4: Cell membranes allow water and water-soluble substances to enter the cell.

The movement of water through a semi-permeable membrane is called ___________.

• active transport

• respiration

• osmosis

• diffusion

Which cell is placed into a hypotonic environment? 

• A
• B
• C
• D

 An animal cell placed in a hypertonic (salty) solution will

• Stay the same
• Shrink- get smaller
• Swell- get bigger

Moving from areas of LOW concentration to areas of HIGH concentration is called?

• Passive Transport
• Active Transport
• Diffusion
• Osmosis

Passive transport is called "passive" because it occurs WITHOUT

• cause.

• using energy.

• a concentration gradient.

• a cell wall.

If you were looking for transport proteins, where would you find them?

• in a cell's nucleus

• in a cell's membrane

• in a cell's cell wall

• in a cell's lysosome

Which is true about active transport?

• It requires energy

• it is a type of diffusion

• It moves substances down the concentration gradient

• it moves material from high to low concentration