Defining Diffusion and Osmosis in IB Biology

The video tutorial covers the concepts of diffusion and osmosis. It begins with a demonstration of diffusion using potassium permanganate in water, illustrating how molecules move from an area of high concentration to low concentration, turning the water purple. The tutorial then transitions to osmosis, using dialysis tubing filled with distilled water and glucose solution. The experiment shows how water moves across a semi-permeable membrane from high to low water potential, affecting the mass of the tubing. The video concludes by emphasizing the principles of osmosis and diffusion.

What are the two main topics discussed in the video?

• Diffusion and Osmosis

• Osmosis and Filtration

• Diffusion and Filtration

• Filtration and Evaporation

What substance is used to demonstrate diffusion in water?

• Sodium chloride

• Potassium permanganate

• Glucose

• Distilled water

What happens to the water when potassium permanganate is added?

• It remains clear

• It turns purple

• It turns green

• It turns blue

What is the definition of diffusion?

• Movement of molecules from low to high concentration

• Movement of water from low to high concentration

• Movement of water from high to low concentration

• Movement of molecules from high to low concentration

What are the two solutions used in the osmosis demonstration?

• Salt solution and distilled water

• Glucose solution and distilled water

• Potassium permanganate and distilled water

• Sodium chloride and glucose solution

What is the starting mass of the tube containing glucose?

• 15.000 grams

• 12.500 grams

• 13.647 grams

• 14.070 grams

What is osmosis?

• Movement of molecules from low to high concentration

• Movement of molecules from high to low concentration

• Movement of water from high to low water potential

• Movement of water from low to high water potential

What happens to the mass of the tube containing glucose when placed in water?

• It decreases

• It remains the same

• It increases

• It fluctuates

What happens to the mass of the tube containing water when placed in glucose solution?

• It remains the same

• It increases

• It decreases

• It fluctuates

What is a key characteristic of osmosis?

• It involves only gases

• It occurs across a semipermeable membrane

• It does not involve water

• It occurs in open air