Osmosis

Osmosis

A Passive Cell Transport

DO NOW: Read the procedure for Day 2 of Gummy Bear Osmosis Lab and answer the questions that follow.

Multiple Choice

Procedure 1. Use the scale to weigh the piece of ____________.

• Gummy Bear

• wax paper

Multiple Choice

Procedure 2. Gently take your gummy bear that was in _____ _______ out of the beaker using a spoon.

• tap water

• 4% salt solution

• 0.2% salt solution

Multiple Choice

Procedure 3. Use the _____ to find the height and width of the tap water bear.

Record your results in the data table.

• weighing scale

• ruler

• spoon

Presentation of Gummy Bear Osmosis Lab Results

​What happened to the gummy bears in tap water? in 0.2 % salt solution? in 4% salt solution?

Review: What do you already know about the Cell Membrane? What is its function?

Multiple Choice

What is the function of a cell membrane?

• Store genetic information
• Produce energy for the cell
• Regulate the movement of substances in and out of a cell

​Recall: What is Simple Diffusion?

​channel

Multiple Choice

What is true of diffusion?

• Diffusion is the process by which molecules move from an area of lower concentration to an area of higher concentration.
• Diffusion only occurs in liquids and gases, not in solids.
• Diffusion is a process that requires energy input.
• Diffusion is the process by which molecules move from an area of higher concentration to an area of lower concentration.

What caused the change in size and mass of the gummy bears after 24 hours?

Fill in the Blanks

What caused the change in size and mass of gummy bears after 24 hours?

Because of the movement of

molecules in and out of the gummy bear.

Osmosis

A Passive Cell Transport

​Osmosis is the diffusion of water molecules
from a high concentration of water to a
low concentration of water across a
partially permeable membrane.

​How do you know which direction will the water molecules move?

​Let's watch a video about
cell transport and solutions

https://www.youtube.com/watch?v=-l-KaBtqLU8

​In hypertonic solutions, water moves out of the cell, causing it to shrink.

​The cell shrinks!

​In isotonic solutions, water concentration on both sides are the same so there is no net movement of water molecules.

​No change in size.

​In hypotonic solutions, water moves into the cell, causing it to swell and potentially burst.

​The cell became bigger!

​THINK of a BIG, SWOLLEN hippopotamus!

​The cell swells in
hypotonic solutions!

1.     Osmosis Diagram- Create a labeled diagram illustrating the process of osmosis with gummy bears. 2.     Osmosis Quiz- Develop a quiz with multiple-choice questions to assess understanding of osmosis and its application to gummy bears. 3.     Osmosis Infographic - Create an infographic that visually explains the concept of osmosis using gummy bears. 4.     Osmosis Poster- Design a visually appealing poster that educates others about osmosis.

​Choice Board

Multiple Choice

What happens to a cell in hypotonic solution?

• The cell will remain the same size.
• The cell will swell or expand.
• The cell will shrink or contract.

Multiple Choice

What happens to a cell in a hypertonic solution?

• The cell will swell or expand.
• The cell will remain the same size.
• The cell will shrink or contract.
• The cell will burst or explode.

Multiple Choice

What happens to a cell in an isotonic solution?

• The cell will swell or expand.
• The cell will remain the same size.
• The cell will shrink or contract.
• The cell will burst or explode.

EXTRA CREDIT!
Research about aquaporins and explain why osmosis is just a special case of facilitated diffusion. Present a short summary of their findings.