Relationships
What is it called when two organisms benefit each other through interactions?
Mutualism.
In an ocean food web, which organism is most likely at the primary producer level? (Hint: makes most of our oxygen!)
Kelp/phytoplankton/algae.
In this process, individuals with traits better suited to their environment tend to survive and leave more offspring. What is this called?
Natural selection.
In the classic peppered moth example during the Industrial Revolution in England, which statement best describes why dark-colored moths became more common in polluted areas?
(Anything that says how Dark colored moths blended in better with their environment, increasing their fitness).
What relationship occurs when one organism benefits while the other is unaffected, such as barnacles hitching a ride on a whale without harming it?
Commensalism.
A grassland has high biomass at the producer level but relatively few apex predators. Which idea about trophic levels best explains this pattern?
Energy is lost as the trophic levels increase, leaving less energy available to higher trophic levels.
This requirement of natural selection means that individuals in a population differ from one another. What is this called?
Heritable variation.
In a population of bacteria exposed to an antibiotic, which scenario best explains why resistant bacteria become more common?
Some bacteria already have genes for resistance, so the successful ones carry this trait to their offspring.
What type of ecological relationship occurs when one organism lives on or in another organism, gaining nutrients while harming but usually not immediately killing the host, as with tapeworms in mammal intestines?
Parasitism.
In a freshwater lake, zooplankton eat phytoplankton, and small fish eat zooplankton. Into which trophic level do the small fish most appropriately fit?
Secondary consumers.
This term describes a trait that increases an organism’s chance of surviving and reproducing in its environment. What is it?
Adaptation.
During a severe drought, seeds became larger and tougher. How did this environmental change affect finch beak evolution?
Finches with naturally larger, stronger beaks were better able to crack the large, tough seeds that remained during drought conditions. This gave them a substantial survival and feeding advantage.
What interaction describes two species that both require the same limited resource, such as two predator species that hunt the same prey in the same habitat, affecting each other's success?
Competition.
A scientist notices that a certain species of crab eats both algae and dead fish. How should this crab’s trophic role be described within its food web?
Omnivores can occupy more than one trophic level.
In a changing environment, which traits will help organisms survive here? What is this factor called?
Selective pressure.
What happens in an insect population repeatedly sprayed with a pesticide?
When the pesticide is applied, many susceptible insects die, but those with resistant traits survive and go on to reproduce.
What relationship describes a close interaction where one organism kills and consumes another, such as a hawk capturing and eating a mouse, influencing both population sizes and energy flow in an ecosystem?
Predation.
Overfishing removes many large predatory fish from a marine food web. Which outcome best illustrates a trophic cascade triggered by this change?
(Anything along the lines of the prey increasing in number and producers decreasing in numbers. This changes the base of the food web!)
In natural selection, this outcome describes a population becoming better suited to its environment over many generations. What is this long-term process called?
Why is the heterozygous genotype for the sickle-cell allele favored?
Heterozygotes are less likely to die from severe malaria, giving them a survival and reproductive advantage in regions where malaria is widespread. Plus, they don't have sickle cell disease. (heterozygote advantage).