17 questions
A company purchased a large forest and cut the trees for lumber. Sunlight which had not reached the forest floor before was now very bright on the bare ground. Holly ferns began to grow rapidly because of increased access to light and moisture.Which population of organisms would be in direct competition with the Holly ferns for the same resources?
Spotted owls
Squirrels
Hawks
Wildflowers
Plants need sunlight to perform photosynthesis. In the tropical rainforest, the survival of a plant depends upon its ability to adapt in order to reach sunlight.
Which of the following is an example of one such adaptation?
Vines that wrap around a tree
Thin, shallow roots that run across the forest floor
Numerous small leaves on one stem
Colorful petals
Which of the following is NOT an example of how biotic factors interact with abiotic factors in an ecosystem?
A lion preys on a herd of gazelle.
Plants remove carbon dioxide from the air and add oxygen.
Animals cause erosion by digging in the dirt.
A lizard raises its body temperature by using heat from the Sun.
Which organisms are in competition for the same food source?
Fox and owl
Spider and fly
Rabbit and mouse
Deer and owl
The graph below shows the percent of seeds from two plant species that sprout when grown in water containing different amounts of salt.
Which of the following best summarizes the effect of saltwater on these plant species?
Species 1 can sprout only in freshwater, and Species 2 can sprout only in saltwater.
Both species can sprout in freshwater and saltwater, but Species 2 can sprout in a higher salt concentration than Species 1.
Both species need salt in their water, but Species 2 needs more salt than Species 1.
Species 1 can sprout only in water with a low salt concentration, but Species 2 is not affected by the salt concentration.
Which organisms in the food web shown above compete for the same food source in this environment?
Grasshoppers and snakes
Hawks and frogs
Frogs and snakes
Decomposers and grasses
The graph below shows the range of water conditions preferred by three species of fish in an Ozark stream.
Water with which of these conditions would cause the most competition for resources among all three species of fish?
Very cold, very clear, and very fast
Very warm, very clear, and very slow
Mild temperatures, some suspended particles, flows very fast
Mild temperatures, some suspended particles, flows at a medium speed
A scientist named Joseph Connell studied two species of barnacles on the shore of a Scottish island. In the area between the average tide and the neap high tide, he found that the population of Species A was smaller than that of Species B. He removed Species B from one area but left both Species A and B in a similar area. The graph below shows the results of this study.
Based on these data, which hypothesis was Connell most likely testing?
The populations of both species of barnacles increase more in warm water than in cool water.
Barnacles grow larger when they are isolated from other species.
The two species of barnacles compete with each other for resources.
The two species of barnacles are closely related to each other.
Black walnut trees produce a nontoxic chemical that becomes highly toxic when it is exposed to air or soil. How does this chemical help black walnut trees compete with plants growing nearby?
By attracting herbivores to the other plants
By suppressing the growth of the other plants
By increasing the photosynthesis rates in the other plants
By limiting the amount of water available to the other plants
Molly filled up three 2 liter jars with aged water and stuck an aquarium thermometer inside each jar. After a couple of days, she added 1 stalk of Elodea to jar 1, 1 stalk of Elodea and 1 guppy to jar 2, and 1 guppy to the jar 3. Predict what happened in Molly’s experiment.
Because animals and plants are interdependent, the fish in jar 3 quickly ran out of dissolved oxygen and showed signs of distress.
The fish in jar 2 showed signs of distress because the production of oxygen by the Elodea was insufficient.
The temperature in jar 1 dropped too low and the plant died.
Because there were no fish in jar 1, the plant in jar 1 increased in size.
Wild Soay sheep live in a cold environment on a small Scottish island. The sheep used to be large because they gained extra weight during the summers in order to survive the harsh winters. A recent change in the island’s climate has caused grass to be available for a longer period each year, so survival conditions for the sheep have become less challenging.
Researchers who study these sheep have most likely observed a decrease in the wild Soay’s —
size
life expectancy
reproduction rates
body temperature
Some scientists studying aquatic plants notice that flooding often leads to a decrease in the rate of photosynthesis among aquatic plants. Flooding causes more sediment to be suspended in thewater. The increased sediment concentration decreases the amount of light that reaches the plants. Why does a decreased rate of photosynthesis lead to a decrease in a plant population?
Less water is available for absorption.
Less tissue is available for plant growth.
Less energy is available for reproduction.
Less soil is available for leaf development.
Scientists are studying the effects of climate change on the Baltic Sea. Some scientists predict that if current trends continue, the Baltic Sea will become less salty, and it will contain less dissolved oxygen. As a result of these changes, the Baltic Sea will have less biodiversity. The location of the Baltic Sea is shown on the map below.
Which statement best explains why biodiversity in the Baltic Sea could decrease if these changes occur?
Fewer types of plants and animals are found in warm water than in cool water.
Plants and animals adapted for living in saltwater will grow more slowly in water that has less salt.
Plants and animals adapted for living in saltier conditions will not be able to survive and reproduce.
Animals adapted for living in warm water will eat all the plants and animals adapted for living in cool water.
Copper compounds are used in large amounts to control the growth of algae and other aquatic plants. Copper interferes with photosynthesis in these organisms. What would be the most likely result of an accidental spill of these compounds in an aquatic environment?
The fish would grow larger than usual.
The zooplankton population would increase.
The plants would increase in size but decrease in number
The plant populations would be reduced.
The organism in the photo is a daphnia, or water flea. Daphnia are tiny aquatic organisms that live in most freshwater habitats. Adults range from less than 1 to 5 mm in length. They are good swimmers and eat mostly algae. Daphnia become mature at 5 to 10 days, and an adult female can produce up to 100 eggs every 3 or 4 days during its 2-month life span. When harmful algae rapidly increase in the daphnia’s environment, daphnia can develop adaptations to tolerate the negative effects of the algae within 10 years.
What characteristic of the daphnia allows the population to adapt to environmental change?
Its small size
Its short generation time
Its freshwater environment
Its herbivorous diet
In Austin, Texas, a well-known salamander inhabits the waters of the spring outflows of Barton Springs. This is the perfect habitat for the Barton Springs salamander since it thrives in fresh and pure continuous flowing water. They may inhabit underground or surface environments. They have been observed in water, under and among rocks and gravel, as well as within plants and algae. They consume small aquatic organisms.
What is the most likely way that humans could have a damaging impact on the Barton Springs salamander?
Polluting the water
Floating down the river
Adding new water vegetation
Adding new crustaceans
Fossils of tropical plants and animals can be found buried in limestone rock in the North Texas area. These plants and animals are no longer found in this region.What is the most likely cause of the disappearance of these tropical plants and animals?
Earthquakes and volcanoes destroyed all the tropical plants and animals.
Tropical animals ate all the tropical plants and everything died out.
Air pollution and acid rain killed off all the tropical plants and animals.
The climate in that area is different today than when tropical plants and animals lived there.