Explain why drinking saltwater causes diarrhea and dehydration. Describe the difference between the size of bacteria and the size of a salt ion. Explain how water’s properties are important for plant cells.

U-tube Consider the image below, which shows a U-tube divided with a selectively permeable membrane. Use arrows to depict how water will move. Hypertonic solution Hypotonic solution Selectively permeable membrane

net water movement

Using the information and drawings, answer the question below: Explain the correlation between the original green area and the area stained by the iodine.

Name a substance that is unique to acid fast cell walls.

Do you think that each sample occupies space? Explain why

Read the following scenario and answer the associated questions. Hydrogen peroxide was added to a piece of potato and potatoes contain the enzyme, catalase. When hydrogen peroxide was added to the potato, bubbles appeared due to the presence of oxygen gas. The presence of the oxygen gas indicates that the catalase was breaking down the hydrogen peroxide into oxygen gas and water. If the hydrogen peroxide was removed and re-added to the potato, would bubbling occur again? Explain why or why not What do you think would happen if the potato in the above question was boiled before being placed into a container with hydrogen peroxide? Why is the reusability of enzymes important?

Use the analogy of the cell as a manufacturing factory to describe the function of the following cell structures: plasma membrane, mitochondria, nucleus, Golgi, ribosomes, lysosomes, endoplasmic reticulum.

Compare and contrast the Gram-positive and Gram-negative bacterial cell walls. Discuss the cell wall components that make the Gram-positive and Gram-negative bacterial cell wall different from each other. Explain why you think one cell wall is stronger than the other.

Examine the plant cell shown below, and answer the following questions about it. A. Does the liquid surrounding this plant cell have a higher or lower concentration of water? B. How can you tell?