Lab #5 Quiz - Brookdale BIO 105

Define lysis and describe the osmotic condition that would cause an animal cell to lyse. Explain why plant cells never lyse.

Lysis is when an animal cell bursts. It occurs when an animal cell is placed in a hypotonic solution for an extended period of time. Plant cells do not lyse because their cell walls prevent them from bursting.

Solvent

The dissolving agent

Osmosis

The movement of water molecules across a selectively permeable membrane

Diffusion

The net movement of molecules from a high concentration to low concentration

True or False: If a selectively permeable membrane separates two isotonic solutions, osmosis will occur.

True

How is water movement across membranes affected by the above tonic solutions?

increase the influx of water into the cell causing the cell to swell or cause the cell to lose water and shrivel

Isotonic Solution

two solutions are equal in concentration

Crenation

when an animal cell loses water and shrivels up (shrinkage of cells when solution is hypertonic)

Tonicity

Compares the relative concentration of two solutions. Tonicity measures the influence a solution will have on cell volume

What factors affect the rate of diffusion

Temperature, Size of molecule

Cell membranes are selectively permeable. What does this mean?

This means that the cell membrane will allow some substances in or out of the cell, but not other substances.

In a salt water solution name the solute

Water

Solute

What gets dissolved

Hypertonic Solution

the solution with the higher solute concentration

Hypotonic Solution

the solution with the lower solute concentration