Interdependence

Two plant species that grow in the same area are shown. Which statement best explains a difference between Plant 1 and Plant 2?

• Plant 1 obtains more water from the soil because of its root surface area and root depth.

• Plant 1 obtains more sunlight because of its root surface area and root depth.

• Plant 2 obtains more water from the soil because of its root surface area and root depth.

• Plant 2 obtains more sunlight because of its root surface area and root depth

Tags

8.11A

Sea anemones and clown fish live together in the ocean. Which statement best describes one way sea anemones depend on clown fish for an abiotic factor in an ecosystem?

• Clown fish protect sea anemones from predatory fish.

• Clown fish decrease competition among sea anemones.

• Clown fish consume the remains of organisms paralyzed by sea anemones.

• Clown fish move water near sea anemones when dissolved oxygen levels are low.

Tags

8.11A

Immediately after a forest fire, the primary consumers in the area will compete most for which biotic factor?

• food

• space

• oxygen

• sunlight

Tags

8.11A

Plants that live on the floors of densely populated forests must compete for sunlight. Which type of leaves are most likely found on plants that are best suited to living on the floor of a dense forest?

• leaves that are needle-shaped

• leaves that are smallest

• leaves that store the greatest amount of water

• leaves with the greatest amount of surface area

Tags

8.11A

Plants grow in many different shapes and sizes. Much of their shape depends on an internal structure that is composed of carbon-containing molecules such as cellulose and lignin. Plants that have a strong internal structure can grow larger than any other plants because their structure can support their size.

Plants obtain the majority of the carbon necessary for building these structural molecules from

• air

• microorganisms

• soil

• water

Tags

8.11A

Trees lose water through transpiration, when water evaporates from leaves. The list describes types of tree leaves that help reduce the amount of transpiration. Which of these is most likely observed in an area experiencing a long-term drought?

• Trees with broad leaves will be more healthy than trees with needlelike leaves.

• Trees with leaves that have waxy coverings will be more healthy than trees without waxed-covered leaves.

• Trees with broad leaves will be more healthy than trees with small, flat leaves.

• Trees with leaves without any hairlike structures will be more healthy than trees with leaves covered by hairlike structures.

Tags

8.11B

A student observes several species of plants growing in a drainage ditch. Some species have short roots, while others have long roots. During periods of heavy rain, the ditch fills with fast-moving water, which uproots more plants that have short roots than long roots.

Which short-term effect will most likely result from a year with more heavy rain than normal?

• Most plants in the ditch will be plants with long roots.

• Most plants in the ditch will be plants with short roots.

• There will be no change in the number of plants with long roots and short roots.

• There will be an equal number of plants in the ditch with long roots and short roots.

Tags

8.11B

Researchers are studying lichens growing on trees in a forest ecosystem. At the beginning of the study, the researchers identified twelve lichen species in the forest. Later, a forest fire happened in the study area. The researchers returned to the area and found only six lichen species.

Which inference is best supported from the researchers' observations?

• Most lichen species are unaffected by forest fire.

• The biodiversity in a forest increases after a fire.

• Certain lichen species are better adapted to survive forest fires than others.

• Forest fires will permanently remove certain species from the ecosystem.

Tags

8.11B

To fight a bacterial infection, a patient was given an antibiotic to take 10 for 10 days. After the patient finished taking the antibiotics as directed, almost all the bacteria were killed. After another 10 days, the patient was sick again with the same type of infection.

What most likely happened?

• A few bacteria survived the antibiotics and stopped reproducing.

• The patient's high fever inactivated the antibiotic, allowing the surviving bacteria to grow rapidly.

• The antibiotic slowed the life cycle of the bacteria.

• Some of the bacteria were resistant to the antibiotic, and they reproduced.

Tags

8.11B

Which of the following is most likely to cause a change in the genetic traits in an isolated population of a ground dwelling lizard species?

• The exposure of an individual lizard in the population to radiation that caused a mutation that is not passed on to its offspring.

• An unusually dry summer in the lizard population's ecosystem.

• The introduction of an invasive predator that preys on the brightest colored individuals in the lizard population.

• A fast moving wildfire that burns the canopy of the trees in the lizard population's ecosytem.

Tags

8.11B