Tadpoles lose their tails as part of their life cycle. At a certain
stage in development, the
human fetus acquires individual
fingers and toes. What occurs
in some cells of both species
to explain these changes?

Nucleic acid certain protein cell membranes certain carbohydrates

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.

What does the hardy-weinberg principle relate to? a. chances of survival of an organism b. frequency of alleles in a population c. natural selection in a species d. causes of evolution among organisms