Problem: While the Grants were on the Galapagos, a drought occurred. As a result, fewer seeds were available for finches to eat. Birds with smaller beaks could crack open and eat only the smaller seeds. Birds with bigger beaks could crack and eat seeds of all sizes. As a result, many of the small-beaked birds died in the drought. Birds with bigger beaks survived and reproduced (see Figure below ). Within 2 years, the average beak size in the finch population increased. Evolution by natural selection had occurred. Two neighboring islands inhabited by thousands of birds each were hit by extreme weather. While Port island experienced wet weather over the past 3 summers, Bank island experienced severe drought, therefore the food supply on the island diminished. Which island had fewer birds with bigger beaks survive?

A: Port

Problem: Hypertension , which is also called "high blood pressure," occurs when a person's blood pressure is always high. Hypertension is said to be present when a person's systolic blood pressure is always 140 or higher, and/or if the person's diastolic blood pressure is always 90 or higher. Having hypertension increases a person's chance for developing heart disease, having a stroke, or suffering from other serious cardiovascular diseases. Hypertension often does not have any symptoms, so a person may not know that he or she has high blood pressure. For this reason, hypertension is often called the "silent killer." Treatments for hypertension include diet changes, exercise, and medication. Foods thought to lower blood pressure include skim milk, spinach, beans, bananas and dark chocolate. Jeremy went to the doctor for his yearly physical along with his wife Brenda. The doctor told Jeremy that his blood pressure was consistently high. Brenda, on the other hand, was told that her blood pressure was in the normal range. Aside from this difference, the overall health of Jeremy and Brenda was similar. Who has a higher risk of suffering from other cardiovascular diseases?

A: Jeremy

Problem: If a solution has a higher concentration of hydronium ions than pure water, it has a pH lower than 7. A solution with a pH lower than 7 is called an acid . As the hydronium ion concentration increases, the pH value decreases. Therefore, the more acidic a solution is, the lower its pH value is. Did you ever taste vinegar? Like other acids, it tastes sour. Stronger acids can be harmful to organisms. For example, stomach acid would eat through the stomach if it were not lined with a layer of mucus. Strong acids can also damage materials, even hard materials such as glass. Alexiev and Sabrina were enthusiastic chemistry students completing the first experiment of their new course. They both started the experiment with pure water, and had to perform different experimental protocols to make changes to the water. At the end of the experiment, both of them measured the concentration of hydronium ions present in their reaction mixtures. Alexiev had a high concentration of hydronium ions present, while Sabrina had a low concentration present in her mixture. Which person's mixture, Alexiev's or Sabrina's, would be less harmful if swallowed?

A: Sabrina's

Problem: As time passes, the number of HIV copies keeps increasing, while the number of helper T cells keeps decreasing. The graph in Figure below shows how the number of T cells typically declines over a period of many years following the initial HIV infection. As the number of T cells decreases, so does the ability of the immune system to defend the body. As a result, an HIV-infected person develops frequent infections. Medicines can slow down the virus but not get rid of it, so there is no cure at present for HIV infections or AIDS. There also is no vaccine to immunize people against HIV infection, but scientists are working to develop one. Mike is a physician who treats HIV-infected patients. Today, he is seeing two patients, patient A and patient B. Patient A is infected with HIV, but patient B is not infected with HIV. Mike is trying to figure out how HIV-infected patient is different from the patient who is not infected with HIV. Would patient B's immune system be stronger or weaker than patient A's immune system?

A:
stronger