Darwin hypothesized that there are definite steps to natural selection. one is populations are large and in the population variation exists. consider this population of disease-causing bacteria. what is the most likely cause for variation in this population?

How is the male reproductive system different from other body systems? it isn’t necessary to vital signs. it monitors other body systems, and adjusts if necessary. it transports items from one system to another. it is the only system that produces hormones in the male.

One of the purposes of transcription is to produce a sequence of bases that

Which of the following is a period in the paleozoic era? devonian cambrian permian all of the above