Porcupines have long sharp hairs called quills. What is the main function of the quills on the porcupine?

Afarmer has applied a pesticide to control a pest population that is affecting her crops. the pest population has reacted as shown below. which best describes the process that the pest population has experienced due to this environmental change? a genetic diversity b natural selection c natural resistance d genetic resistance

Why do some dna fragments move farther than others during gel electrophoresis? a. because their shapes are different b. because they are different types of molecules c. because the samples are different colors d. because their masses are different

How do water’s relative densities as a solid and a liquid differ from that of most other substances? water’s solid and liquid forms have different densities, while most other substances have solid and liquid forms with similar densities. water’s solid and liquid forms have similar densities, while most other substances have solid and liquid forms with different densities. water’s liquid form is less dense than its solid form, while the opposite is true of most other substances. water’s solid form is less dense than its liquid form, while the opposite is true of most other substances.