Perform an experiment of regeneration on flatworms. Observe the cut ends of the flatworms using the hand lens or the dissection microscope immediately after cutting. What do you see?
Are there distinct differences between the two ends?
Observe the cut ends of the flatworms over a period of several days. Do the flatworm halves continue to exhibit the same degree of difference that was seen right after they were cut in two?

What kinds of changes occur in the flatworms as they recover from having been cut in two?

Identify the missing parts of the carbon cycle

During crossing-over, a. genetic material is exchanged between nonsister chromatids, resulting in new combinations of alleles. b. nonsister chromatids from each homologous chromosome of a tetrad are exchanged, resulting in new combinations of alleles. c. one homologous chromosome of a tetrad is exchanged with another tetrad, resulting in new combinations of alleles. d. sister chromatids from each homologous chromosome of a tetrad are exchanged, resulting in new combinations of alleles. e. genetic material is exchanged between sister chromatids, resulting in new combinations of alleles.

How does climate change affect producers?