A scientist is evaluating a proposal for raising large numbers of fish in ocean pens for human consumption. As part of the evaluation, the scientist is designing a plan for investigating how fish in the ocean pens might affect nearby ecosystems. Which of the following is the most appropriate factor to use as the dependent variable in the experimental investigation? a. the amount of metabolic wastes in the water where the fish are being raised
b. the water temperature in the natural habitat of the fish being studied
c. the types of fish that are preferentially consumed by humans

Examine the two squirrel populations in the accompanying figure. the populations are separated by a geographic barrier. if after a long period of time the two species are no longer separated, what evidence is needed to determine if speciation has occurred? the figure shows two populations of squirrels separated by a geographic barrier. examine the two squirrel populations in the accompanying figure. the populations are separated by a geographic barrier. if after a long period of time the two species are no longer separated, what evidence is needed to determine if speciation has occurred? the figure shows two populations of squirrels separated by a geographic barrier. polyploidy is creating new species. the two populations are not interbreeding freely. hybrid offspring of the two populations begin to appear. one species will increase into a population size twice as large as the other species.

Which statements describe resources? one of the factors people use when deciding where they will live is the availability of resources. renewable resources have little value for people. resources are unevenly distributed throughout the world. energy is the world resource which has the highest use. the use of nonrenewable resources has decreased in recent history. the use of resources is evenly distributed throughout the world. the world's oil supply will last for the next forty years if its use continues as expected.

The picture showed normal blood cells which are around and sickle cells which appear much longer people with sickle-cell suffer from the sickle cell anemia which is inherited diseaseit is caused by a change in gene responsible for production of hemo goblin this type of change is known as an