Ecology Test Review

Approximately 50 million acres of tropical rainforest are cleared each year. Which effect most

likely would result from the clearing of these forests?

• a decrease in soil erosion

• a decrease in biodiversity

• an improvement in air quality

• an improvement in water quality

A ship sank in the Atlantic Ocean, near Cape Town in South Africa, and spilled 1300 tons of oil. Which of these would be the most likely effect on the ocean ecosystem from this spill?

• Ocean plankton populations would increase after obtaining nutrients from oil

• Predator numbers would increase as animals killed by oil were eaten.

• Sea bird numbers would decrease due to ingesting oil while preening.

• Bottom-dwelling shellfish populations would be unaffected.

The cane toad was introduced in Australia in the 1930s by farmers to control the beetles that fed on sugarcane crops. The cane toad can weigh up to a kilogram and eats almost any insect that fits in its large mouth.

Though the cane toads were able to control the beetle problem, what threat did the toads pose to the native Australian frog populations?

• Cane toads eat the eggs of the native frogs.

• Cane toads compete with the native frogs for food.

• Cane toads pollute the water in which native frogs breed.

• Cane toads mate with native frogs to form new species.

A frog species is highly dependent on water for its reproduction and survival. How could an increase in environmental temperature due to global warming pose a threat to the frog species?

• Increased temperatures could increase sweating, which results in the deaths of adults due to dehydration.

• Increased temperatures could dry out the breeding pools of frogs, which results in the deaths of

  tadpoles and eggs.

• Increased temperatures could decrease the appetites of frogs, which results in the deaths of tadpoles and adult frogs due to starvation.

• Increased temperatures could force adult frogs to drink excess water, which results in their deaths

  due to low salt concentrations in their bodies.

Following a massive oil spill in the Gulf of Mexico, oil contaminates the freshwater streams of Louisiana, decreasing the crayfish population. How would this most likely impact the bass (predator) population in local streams?

• They would remain unchanged.

• They would increase and then decrease.

• They would increase due to an increasing food supply.

• They would decrease due to declining food supply.

Which human action has had the most positive

ecological impact on the environment?

• overhunting predators to reduce the death of their prey

• reforestation to reduce the amount of carbon dioxide in the atmosphere

• introduction of non-native species such as kudzu into the U.S. to reduce erosion

• use of pesticides to reduce crop damage by insects

How can the use of electric rather than gas powered vehicles benefit the environment?

• Electric vehicles generate less air pollution than gas-fueled cars.

• Electric vehicles can transport more people at a time.

• Electric vehicles are made from recycled materials.

• Electric vehicles run faster than gas-fueled vehicles.

Deforestation in the rainforest can lead to localized extinctions of populations of some organisms. Once an area is deforested, which is most likely to decrease and result in organisms’ extinctions?

• the amount of annual rainfall

• competition between consumers

• the energy available to producers

• diversity of the resources in the habitat

A particular species of snake was accidentally introduced into a region where it had no natural enemies. These introduced snakes fed on birds and insects that were the food of native snake species. Over the next few years, the introduced snake population grew rapidly in size. How will the introduced snakes most likely impact the native snake population?

• Native snakes will mate with the invaders to form a new species.

• Native snakes will adapt to eating different varieties of food.

• The native snake population will increase as it migrates to new areas.

• The native snake population will decrease as competition for food increases.

Which cellular process removes carbon dioxide from the atmosphere?

• active transport

• aerobic cellular respiration

• asexual reproduction

• photosynthesis