Osmosis Flashcards

Questions and Answers

During osmosis, individual molecules move:

Away from a membrane

Towards a higher concentration

All directions with equal probability (correct)

In one direction only

What causes the SimCell membrane in the Cell-O-Scope simulator to jiggle back and forth?

Pressure against the membrane

What will happen to the osmotic pressure of blood cells placed in a hypertonic solution?

Decrease

What will happen to the osmotic pressure of blood cells placed in an isotonic solution?

Neither increase nor decrease Signup and view all the answers

At what point does a system reach equilibrium in osmosis?

When the concentration of solute molecules on both sides of a membrane are equal Signup and view all the answers

What should happen to water molecules in a SimCell with 20 hemoglobin molecules and 480 water molecules placed in extracellular fluid with 20 dextrose molecules and 480 water molecules?

Water molecules will move back and forth equally across the membrane Signup and view all the answers

What will happen to a SimCell containing 20% alcohol and 80% water placed in a solution containing 40% alcohol and 60% water?

It will expand due to net movement of alcohol into the cell Signup and view all the answers

What will happen to water molecules in a SimCell containing 20 hemoglobin molecules and 480 water molecules placed in extracellular fluid with 40 dextrose molecules and 960 water molecules?

More water molecules will flow into the SimCell than out of it Signup and view all the answers

What are the water balance challenges faced by freshwater and saltwater fish?

Freshwater fish must get rid of excess water and saltwater fish must retain the water they have Signup and view all the answers

Study Notes

Osmosis Overview

Osmosis involves the movement of individual molecules in all directions with equal probability.
A system reaches equilibrium when the concentration of solute molecules is equal on both sides of a water-permeable membrane.

Cell Membrane Behavior

In a Cell-O-Scope simulation, membrane jiggling occurs due to pressure against the membrane.
A water-permeable membrane allows for the movement of water molecules across it depending on solute concentrations on either side.

Impact of Solutions on Blood Cells

Blood cells placed in a hypertonic solution experience a decrease in osmotic pressure.
In isotonic solutions, osmotic pressure remains stable, neither increasing nor decreasing.

Water Movement Dynamics

When placing a SimCell with equal concentrations of hemoglobin and water inside and outside, water molecules will move back and forth equally.
If a SimCell contains 20% alcohol in a solution with 40% alcohol, the cell expands as alcohol moves into it due to the concentration gradient.
A SimCell surrounded by a mixture with a higher water concentration than in the cell will see more water moving into the SimCell.

Osmosis in Aquatic Life

Freshwater fish struggle with excess water intake, needing to expel it, while saltwater fish focus on retaining the limited water available to them.

Description

Test your understanding of osmosis with these graded flashcards. Each card covers key concepts related to the movement of molecules and the behavior of cells in different solutions. Perfect for students looking to reinforce their knowledge in cell biology.