Unit 2 Day 5 Hw#4

_______ 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

Which type of passive transport uses proteins to help molecules pass through the membrane?

• Diffusion
• Facilitated diffusion
• Osmosis
• All of the above

Passive Transport

• Does require cell energy

• Does NOT require cell energy

What is diffusion?

• when molecules move from a low concentration to a high concentration 
• when molecules move from a high concentration to a low concentration.
• no movement 
• molecules move everywhere

When both inside and outside of a cell have the same amount of water it is said that the cell has reached a state of

• Osmosis
• Diffusion
• Equilibrium

What biomolecule is number one pointing to?

• Lipid

• Protein

• Nucleic Acid

• Carbohydrate

Phospholipids have a -

• nonpolar head and a nonpolar tail.

• polar head and a polar tail.

• nonpolar head and a polar tail.

• polar head and a nonpolar tail.

A cell has a salt concentration of 0.7 NaCl.  It was placed in a beaker containing pure water.  The water is considered a - 

• hypotonic solution.

• isotonic solution.

• myotonic solution.

• hypertonic solution.

Susan sprayed perfume in one corner of the room.  John, who sits across the room and is allergic to perfume, soon begins to sneeze.  Perfume travels across the room by - 

• active transport.

• osmosis.

• endocytosis. 

• diffusion.