Biology STAAR Review Day 5 - Ecology

What would be the most likely effect of a wildfire that burned a large area of a forest? (12D)

• More sugars and starches would be available for animals in the area.

• The availability of fossil fuels for use by industries in the area would be reduced.

• Less carbon dioxide would be removed from the atmosphere in the area by plants.

• An increase in animal respiration would increase the release of carbon dioxide in the area.

The San Marcos salamander, Eurycea nana, is a light reddish-brown translucent salamander about 2–5 cm in length. E. nana is found only in Spring Lake and a portion of the San Marcos River.

Which human activity would most likely decrease the ability of the salamanders to survive? (12E)

• Increasing water consumption that decreases the flow of clean water from the springs that feed the river

• Public transportation that reduces the number of automobiles that contribute to pollution runoff into the river

• Tourism that helps fund the educational programs related to river ecosystem conservation

• The addition of a new food source into the river that limits competition for resources

A partial Texas food web is shown.

The populations of which organisms will most likely increase as a result of a disease that suddenly reduced the population of Texas horned lizards? (12C)

• Grasses and ants

• Ants and grasshoppers

• Grasshoppers and Texas cottonmouths

• Texas cottonmouths and red-shouldered hawks

During secondary succession, which of these best describes why decomposing pioneer plants give way to larger, more complex plants species, such as hardwood trees? (11B)

• Increased amounts of sunlight are able to reach the ground while the pioneer species are decomposing.

• Increased soil temperatures from decomposing pioneer species help tree seeds germinate more quickly.

• Increased amounts of decomposing pioneer species remove nutrients that tree seedlings need to grow and mature.

• Increased amounts of soil from decomposing pioneer species allow plants with more extensive root systems to become established.

The diagrams show a partial food web containing the Glyptapanteles wasp and the life cycle of this wasp.

Based on the two diagrams, which list correctly identifies the relationships Glyptapanteles wasp larvae have with other organisms? (12A)

• Competition: stinkbugs

  Parasitism: geometrid moths

• Competition: geometrid moths

  Commensalism: stinkbugs

  Mutualism: guava and eucalyptus trees

• Competition: stinkbugs and geometrid moths

  Commensalism: guava and eucalyptus trees

• Parasitism: geometrid moths

  Commensalism: stinkbugs

  Mutualism: guava and eucalyptus trees

Some species of millipedes will roll into a ball when threatened, while other species of millipedes can secrete noxious chemicals from their bodies.

These adaptations allow the millipedes to — (12B)

• survive in different temperatures

• avoid different types of predators

• conserve different amounts of energy

• blend into different types of environments

The ocean sunfish (Mola mola) is a large, flat fish that spends most of its time in deep water feeding mainly on jellyfish. Sunfish often have many species of copepods, small crustaceans, that bury their heads into the soft tissue of the sunfish. Sunfish will swim to the surface of the water and lie sideways, allowing seabirds to eat the copepods from their skin.

Which list describes the types of relationships the sunfish has with other marine organisms? (12A)

• Seabirds: mutualism

  Jellyfish: predation

  Copepods: parasitism

• Seabirds: parasitism

  Jellyfish: commensalism

  Copepods: predation

• Seabirds: predation

  Jellyfish: mutualism

  Copepods: commensalism

• Seabirds: commensalism

  Jellyfish: parasitism

  Copepods: mutualism

Grassland ecosystems in Texas have evolved to depend on periodic fires to return nutrients to the soil and encourage plant reproduction. Humans have prevented fires in many of these grassland areas, resulting in plant and animal communities with little diversity. Wildlife biologists often recommend purposefully starting fires called prescribed burns, which are monitored and controlled, in grassland ecosystems every 3 to 4 years. These biologists observe greater diversity in plant and animal life in the years following a prescribed burn.

What natural processes are the biologists attempting to imitate? (11B)

• Biomagnification

• Succession

• Population bottleneck

• Species extinction

A biomass pyramid of an ecosystem is shown.

Which statement provides the best explanation for the difference in biomass of organisms found at each trophic level? (12C)

• Organisms at higher trophic levels have less energy available to them than organisms at lower trophic levels.

• Organisms at higher trophic levels require smaller habitats than organisms at lower trophic levels.

• Organisms at lower trophic levels provide less energy than organisms at higher trophic levels.

• Organisms at lower trophic levels outcompete organisms at higher trophic levels.

Which role of protists has the most positive effect on maintaining the plant population in an ecosystem? (11A)

• Protists are a major food source for animals.

• Protists produce approximately 75 percent of the oxygen on Earth.

• Protists decompose dead materials, returning nutrients to the soil.

• Protists found in the gut of animals assist in digestion.