Science 8B Unit 1 Test Review

Based on the pyramid, which organism(s) provide the MOST available energy?

• predator fish

• birds and mammals

• insects and zooplankton

• phytoplankton

A biome associated with fluctuations in water salinity will MOST LIKELY be found near the letter

• A

• B

• C

• D

Cacti and succulents can survive in the desert MOST LIKELY because they both

• need direct sun

• can store water

• have long tap roots

• have chlorophyll for photosynthesis.

Which biome would be the MOST hostile for animals displaced from a tropical rainforest?

• tundra

• grassland

• temperate forest

• tropical forest

An ecological pyramid is sometimes used to show both the flow of matter and energy in an ecosystem. The pyramid narrows as matter and energy flow from the bottom to the top. Draw a conclusion about what this pyramid tells you about the energy in this ecosystem.

• Energy stays the same. Only the number of living things change.

• Energy decreases from the top to the bottom as organisms are larger in size.

• Energy increases from bottom to top because the organisms get larger in size.

• Energy decreases from bottom to top because some is used at each level for life processes

A marine ecosystem off the California coast consists of leatherback turtles that feed on jellyfish, and killer whales that prey on the leatherback turtles. Habitat loss and fishing have been identified as the main reasons for the reduced numbers of leatherback turtles, who are on the verge of being declared an endangered species. What would be the first effect on the ecosystem if habitat loss and fishing continue unchecked?

• A spurt in the population of jellyfish

• A spurt in the population of killer whales

• A change in the feeding habits of jellyfish

• A migration of jelly fish from the ecosystem

The tundra is cold year-round. it has short cool summers and long, severe winters. The tundra has a permanently frozen sublayer of soil called permafrost. Like the desert, the tundra receives little precipitation, about 4 to 10 inches per year, and what does fall is usually in the form of snow or ice. It has long days during the growing season, sometimes with 24 hours of daylight, and long nights during the winter. Which adaptations would you expect to see in plants growing in the tundra?

• leaves with hair help shade the plant, reducing water loss.

• small and grow in clumps for protection form the wind and cold

• deep roots to help capture nutrients from deep below the surface

• tall plants with broad, thin, and waxy leaves leaves so water easily runs off

The population of mice in a local forest ecosystem has recently died out due to disease. In the past, these mice were the main predators of the forest beetles. What is the best prediction about what will happen to the beetles?

• The drop in the mouse population will lead to a drop in the beetle population.

• The drop in the mouse population will lead to no change in the beetle population.

• The drop in the mouse population will lead to an increase in the beetle population

• The increase in the mouse population will lead to an increase in the beetle population..

All living things within an ecosystem are interdependent. A change in the size of one population affects all other organisms within the ecosystem. One well known predator/prey relationship is between Canadian lynx and snowshoe hare. Examine the graph and develop a logical conclusion regarding the population of Canadian lynx if there is an decrease in snowshoe hare population.

• The Canadian lynx population will decrease

• The Canadian lynx population will increase.

• The Canadian lynx population will remain the same.

• The Canadian lynx population will remain the same because Canadian lynx can only eat so may snowshoe hare.

A characteristic of the open-loop system is that it does not use feedback to determine if its output has achieved the desired goal of the input. This means that the system does not observe the output of the processes that it is controlling. Closed-loop systems employ feedback and a reference of correctness. Deviations from the norm are detected and corrections made in order to maintain a desired output. The image shown is the Food web. What kind of system is the Food web?

• feedback system

• open-loop system

• regulated system

• closed-loop system