Ecology Keystone Practice

Which description is the best example of a population?

• all of the red foxes in a forest

• all of the red foxes in every forest

• all of the organisms in a forest

• all of the organisms in every forest

Yellowstone National Park contains many different plants and animals that interact with one another. What is this level of ecological organization called?

• Ecosystem

• Organism

• Population

• Community

Which set of ecological organization levels is most likely to contain the largest variety of species?

• multiple biomes in a biosphere

• multiple ecosystems in a biome

• multiple individuals in a population

• multiple populations in a community

Which ecological term includes everything represented in

the illustration below?

• Community

• Population

• Ecosystem

• Species

At the bottom of a stream, various bacteria, fungi, protozoans, vertebrates, and invertebrates all live in one common area. Which terms best defines this group of organisms?

• Biome

• Population

• Ecosystem

• Community

A student studying the biosphere makes a list of biotic and abiotic characteristics of various biomes. Of the four choices, which characteristic is considered a biotic factor?

• dry, sandy, nutrient-poor soil in a desert

• less than 25 cm of precipitation in a desert

• evergreen trees present in a coniferous forest

• temperature range of -40 to 40°C in a grassland

Rainfall and leaves dropping from the surrounding forest greatly affect the amount and quality of water entering an ecosystem. The water quality affects the microbes and vertebrate populations within the ecosystem. Which feature of this ecosystem is an example of an abiotic factor?

• Leaves

• Rainfall

• Microbes

• Vertebrates

An ecosystem includes the organisms listed in the table.

Identify the initial source of energy for the ecosystem.

• plants

• birds

• sunlight

• eagles

Which energy transfer most likely occurs between organisms in the food web?

• from owl to fox

• from rabbit to fox

• from sparrow to grass

• from mouse to grasshopper

Which ecological term best describes the polar bears in the cartoon below?

• Herbivores

• Parasites

• Carnivores

• Producers