On the galapagos islands, darwin observed tortoises with domed and saddle-shaped shells. how did darwin's observations of these tortoises him form the theory of evolution by natural selection? a. the tortoises to confirm that environmental changes cannot affect the characteristics of a species. b. the tortoises to confirm that two similar species do not necessarily share a common ancestor. c. the tortoises provided evidence that different species have adaptations suited to their particular environments. d. the tortoises provided evidence that the galapagos had been colonized by tortoises multiple independent times.

Lucia is walking barefoot in her yard. she accidentally steps on a nail. how will her nervous system work to generate a reaction? arrange the eventschronologically.

In which part of the body is a ball-and-socket joint found?

Embryonic stem cells are cells derived from an embryo. these cells can be used to create new tissues for patients suffering from certain illnesses and disorders. which statement best summarizes why the use of embryonic stem cells could be seen as unethical? a. some people consider embryos to possess rights equal to those of fully developed human beings. b. extracting stem cells from embryos is a very energy-intensive process, which consumes resources that could be used elsewhere. c. embryos are difficult to obtain, so the monetary cost of using them for research outweighs their benefit. d. the process of extracting stem cells from embryos generates biohazardous waste that cannot be safely disposed of.