Question

1. isle royale is a large island in lake superior. woodland caribou and lynx used to live on the island, but they disappeared in the early 1900s. at that time, moose made their way to the island. by 1925, the moose population on isle royale rose to about 2,000 individuals. wolves arrived on the island in the 1950s. which best explains how the moose population grew so rapidly?

a. the death rate was greater than the birth rate.
b. there was unlimited food for the moose to eat.
c. the birth rate was constant, and few moose died.
d. there were few predators to control the population.

1. male peacocks have large brightly colored tail feathers. what is the main reason for this?

a. to attract potential mates
b. to distract potential predators
c. to help catch food
d. to preserve warmth

1. gasoline for cars is produced from fossil fuels. using gasoline can most directly lead to which environmental problem?

a. soil erosion
b. water pollution
c. wildlife extinction
d. global warming

1. after fields of crops are harvested, parts of the plants remain on the ground. for many years, farmers have mixed these plant remains into the soil. what likely results from this practice?

a. more minerals are lost from the field.
b. more nutrients in the soil are dissolved.
c. the organic matter in the soil increases.
d. the number of organisms in the soil decreases.

1. which substance do biochemists often search for in fossils to help better understand the evolutionary relationships of the organism that formed the fossil?

a. atp
b. dna
c. iron
d. oxygen

Explanation:

1. Before wolves arrived, the moose had no major predators on the island, allowing their population to grow rapidly as there was no population control from predation. Option b is incorrect because food is never truly unlimited, just abundant initially. Option a would cause population decline, and option c is inaccurate as death rates were not near zero.
2. Male peacock tail feathers are a classic example of a sexual selection trait used to attract female peahens for mating.
3. Burning gasoline releases carbon dioxide, a greenhouse gas that traps heat in the atmosphere, leading to global warming.
4. Mixing harvested plant remains into soil adds decomposable organic material, increasing the soil's organic matter content which improves soil health and fertility.
5. DNA contains the genetic code of an organism, which can be extracted (when preserved) from fossils to map out evolutionary relationships between extinct and living species.

Answer:

1. d. There were few predators to control the population.
2. a. to attract potential mates
3. d. global warming
4. c. The organic matter in the soil increases.
5. b. DNA