In population genetics, directional selection is a mode of natural selection in which an extreme phenotype is favored over other phenotype, causing the allele frequency to shift over time in the direction of that phenotype
Answer:
Fossil fuels, including coal, oil and natural gas, are currently the world's primary energy source. Formed from organic material over the course of millions of years, fossil fuels have fueled U.S. and global economic development over the past century. Yet fossil fuels are finite resources and they can also irreparably harm the environment. According to the U.S. Energy Information Administration, the burning of fossil fuels was responsible for 76 percent of U.S. greenhouse gas emissions in 2016. These gases contribute to the greenhouse effect and could lead to potentially catastrophic changes in the Earth’s climate. Technologies such as Carbon Capture and Storage (CCS) may help reduce the greenhouse gas emissions generated by fossil fuels, and nuclear energy can be a zero-carbon alternative for electricity generation. But other, more sustainable and less risky solutions exist: energy efficiency and renewable energy.
As light intensity increases, the rate of photosynthesis increases. As the intensity decreases, so does the rate of photosynthesis
