Angraecoid orchid flowers have a long, tubular throat, while African moths have long probosci for gathering nectar. The orchids are dependent on the moth for pollination, while the moths are dependent on the orchids for nectar. Which pattern is best represented by this pair of organisms? A. coevolution B. adaptive radiation C. convergent evolution D. divergent evolution A

Why is angiosperm reproduction so effective. A Why is angiosperm reproduction so effective? A. Seeds are their only form of reproduction. B. Their seeds are uncovered and easily spread. C. They reproduce through both sexual and asexual reproduction. D. Their leaves and stems contain many spore-producing structures. C

How do viruses, such as the tobacco mosaic virus, infect plants. A How do viruses, such as the tobacco mosaic virus, infect plants? A. They enter the plant through insect bites or wounds. B. They enter the plants through osmosis in leaf cells. C. They are absorbed through the stomata of the leaves. D. They are absorbed through the roots of the host plant. A

Which species most likely coevolved with flowering plants. A. bees B Which species most likely coevolved with flowering plants? A. bees B. Deer C. Squirrels D. non-flowering plants A

Which adaptation would be most beneficial to a mammal in reducing its body temperature? A. oil glands B. sweat glands C. increased muscular movement D. decreased blood flow to appendages B

More than 300,000 Americans have died from AIDS since 1981 More than 300,000 Americans have died from AIDS since 1981. However, the virus that causes AIDS does not directly kill the host. Which best explains how this virus leads to the eventual death of the host? A. The virus destroys nerve and brain cells. B. The virus affects muscle cells, which eventually weakens the heart. C. The virus weakens the immune system, allowing for opportunistic diseases. D. The virus causes a loss of respiratory function, leading to the inability to breathe. C

Which characteristics have many butterflies acquired through evolution to defend themselves against birds? A. Butterflies have developed larger wings, so they can fly fast and escape the birds. B. Butterflies have developed marks on their wings that look like eyes and confuse the birds. C. Butterflies have developed larger antennae so they can detect birds before they get too close. D. Butterflies have developed a proboscis that can sting birds with a toxin that prevents the birds from wanting to eat them. B

Which mechanism is used by many fruit-bearing plants to spread seeds? A. sporulation B. wind dispersal C. water dispersal D. animal consumption D

Why do some people who are vaccinated against influenza (the flu) still contract the virus? A. The vaccine does not cover all strains of influenza mutations. B. The vaccine may have been given as a nasal spray rather than an injection. C. People who receive the vaccine and have not had the influenza virus previously are not protected. D. People who have had the influenza virus and also receive the vaccine are the only ones who are protected. A

Which would most likely occur in an aquatic protist population that relied on a declining supply of decaying matter for energy? A. Genetic alterations would be minimal, and the protists would begin to consume each other. B. Genetic alterations of the protists may give some the ability to gain nutrition through photosynthesis. C. Over time, the protists would develop the ability to utilize freshwater as their primary source of nutrition. D. Over time, the protists would become complex multicellular organisms with increased mobility to feed on terrestrial organic matter. B