7th Grade CBA #3 Review

Which would result in the most diverse offspring?

• an orchid with a flower structure that forces self pollination
• planting a cutting from a potato to grow a new potato plant
• bees bringing pollen from the flower of one plant to the flower of another
• an amoeba in a fresh water pond reproducing through binary fission

Some moths have a brown body and brown wings while other moths have a white body and white wings. The brown moths often rest on the bark of pine trees and the white moths rest on the white bark of aspen trees. If all aspen trees in an area were cut down, what would be the likely result?

• more brown moths will survive than white moths because predators will be able to spot the white moths more easily. Over time, there will be no white moths in the area
• The white moths will grow brown wings in order to blend in with the environment. Over time, there will be no white moths in the area.
• The white moths will migrate to a new area where aspen trees are found. The brown moths will remain in the original area. The number of brown moths will increase.
• The white moths will rest on the remaining trees. Over time, they will become brown moths, so the number of moths will increase.

Which internal structure is an adaptation that provided organisms with the function to perform gas exchange on land?

• gills
• lungs
• hollow bones
• chambered heart

Mudskippers are a species of fish which, over thousands of generations, have developed adaptations that allow them not only to survive outside of the water, but to actually travel from one water source to another. What environmental condition likely led to these adaptations?

• lower temperatures
• frequent droughts
• larger predators
• increased precipitation

Galapagos finches are birds that live on islands off the coast of South America. The finches on the various islands are very different from each other. As a result of the different food resources on the islands, which of the following structures of the Galapagos finches experienced the greatest change through natural selection?

• head size
• eye shape
• feather color
• beak shape

Antibiotics are used to kill bacteria or prevent them from infecting cells. Over time, many bacteria have become resistant to antibiotics. That means that the antibiotics no longer kill the bacteria. Through which process do bacteria become resistant to antibiotics?

• cloning
• natural selection
• selective breeding
• genetic engineering

Which of these is an example of natural selection?

• farmers crossbreed two types of cows
• dogs of the same breed that have a desirable coat color are bred with one another to produce offspring with that same coat color
• giraffes with longer necks survive a dry season by eating leaves from the tops of trees. Those giraffes breed more successfully that year
• people capture yellow fish from a pond and breed only the most attractive ones

What is variation?

• an explanation for why some organisms survive and other to not
• a range of physical traits among members of a species
• the process by which populations change over time
• a group of organisms that live longer in the same ecosystem

Energy flows from:

• wildflowers to the grasshopper to the field mouse
• wildflowers to the rattlesnake to the grasshopper
• wildflowers to the field mouse to the grasshopper
• the grasshopper to the rattlesnake to the field mouse

In a food chain, what organism provides the initial energy for the chain?

• producer
• consumer
• herbivore
• decomposer