Read each of the scenarios below, and respond to each question that follows in the space provided. You may refer to your notes, textbook, a reliable online source, and/ or work together in order to determine the best responses.

Scenario #1: A person became stranded on an island following a shipwreck. In her quest to quench her thirst, she found no freshwater sources. Knowing that she needed to consume water relatively soon in order to survive, she used her hands as a ‘cup’ and began drinking saltwater. Finally, a couple of days later a rescue plane arrived at the island, but to their dismay, found her dead.

Saltwater contains roughly 3.5% dissolved salts (solute), while red blood cells within our body contain 0.9% dissolved salts. What type of environment did the saltwater create for this person as it was consumed? (Hypotonic, Hypertonic, Isotonic)

What would happen to the red blood cells within her body as a result of this type of environment?

Scenario #2: A male athlete was training for a marathon outside on a hot, summer day. In attempting to quench his thirst he consumed about 3 liters of bottled water within 2-3 hours. Not long after, he suffered from a severe headache, nausea, and vomiting.

What type of environment did the bottled water create for the male athlete? (keeping in mind that red blood cell salt concentration is 0.9%, and salt concentration is much less in bottled drinking water.)

What would happen to the red blood cells within his body as a result of this type of environment?

Scenario #3: Each of the following solutions were placed into a bag containing a semi-permeable barrier:

Bag A: 50% glucose solutionBag B: 20% glucose solution

Each bag of solution was placed into a separate beaker containing 100% water. Which bag will gain weight? Explain your answer.

Scenario #4: An inexperienced farmer wanted to greatly enhance his corn crop quality and yield. In order to accomplish this he doubled the amount of fertilizer that was recommended in the instructions on the bag. Following a slow and steady rain shower, the young farmer was shocked to see that his corn crop had not improved. Instead of erect, bright green, and lively looking plants, the leaves were somewhat pale and withered.

What type of environment did the extra fertilizer create for the corn following the rain? What would be the result of this environment on the plant cells?

Describe the role of a central vacuole in plants:

What is turgor pressure? Why is turgor pressure beneficial to plants?

Based on your previous response, which type of environment (hypertonic, hypotonic, isotonic) will best maintain a plant cell’s turgor pressure?