Lab 2: Membrane Transport- Diffusion, Osmosis, Tonicity

Diffusion

net movement of a substance from region of
high concentration to low concentration

what is this experiment showing?

• Diffusion

diffusion in liquids

what is this experiment showing?

• diffusion rate vs. molecular weight

what diffused fastest and why?

KMnO₄; because of the molecular weight

what is this experiment showing?

Diffusion and membrane permeability

what is the color of the breaker?

amber color

what is the color of the bag?

blue to black

what is in the bag

starch

what was the substance that crossed over?

iodine(IKI)

Osmosis

diffusion of water through selectively permeable membrane

how is the movement of osmosis

waters moves from higher water concentration (lower solute concentration) to an area of lower water concentration

what is this experiment showing?

Osmosis

which way is the water moving?

Water molecules move into the thistle tube

what is the name of the tool used?

thistle tube osmometer

what is the solution being showing in the cell?

• hypertonic

• isotonic

• hypotonic

isotonic

what does it mean when the cell is isotonic

solute concentration equal to inside the cell

what does isotonic mean

the cell is normal

what is the solution being showing in the cell?

• hypertonic

• isotonic

• hypotonic

Hypotonic

what is the movement inside the cell?

solute concertation is less than inside the cell

what happens to a cell inside of a hypotonic solution?

Hemolysis

what is the solution being showing in the cell?

• hypertonic

• isotonic

• hypotonic

hypertonic

what is a hypertonic solution mean?

solute concentration is greater than that inside the cell

what happens to the cell in the hypertonic solution?

crenation

identify the cell and what solution they are in?

isotonic, normal

identify the cell and what solution they are in?

crenated; hypertonic

identify the cell and what solution they are in?

hypotonic; hemolyzed

Filtration

forced movement of a fluid across a membrane whose pore size restricts the passage of solutes

what does the filtration experiment represent in the body?

kidneys

what is this experiment represent in the body?

kidneys

what was in the filter paper

water, copper sulfate, charcoal and starch

what passed through the filter paper?

water, copper sulfate, and starch

How do we know that the charcoal didn’t pass through

the charcoal is still in the top part

how do we know that the starch passed through

iodine(IKI) testing

active transport

require cellular energy/ (ATP)

what is active transport movement?

lower concentration → higher concentration

what is an example of active transport?

sodium potassium pump & proton pump

vesicular transport

cellular packaging

endocytosis

vesicular transport of large molecules into a cell

phagocytosis

“cell eating”

phagocytosis is done by what type of cell

white blood cells

pinocytosis

cell drinking

What is an example of pinocytosis in the body

absorption of some nutrients by cells in the S.I.

how is pinocytosis done in the cell?

absorption of ECF

receptor mediated

specific receptor sites located within the cell membrane

an example of receptor mediated in the body

cholesterol uptake ↑ by liver cells

exocytosis

vesicular transport of molecules out of cell

examples of exocytosis

newly synthesized proteins (enzymes, insulin)