Which substances are most commonly used as building blocks in the synthesis(making) of some lipids a.) amino acids and nucleotides b.) sugars and starches c.) glycerol and fatty acids d.) starches and enzymes

Which are evidence of seafloor spreading? check all that apply. molten material magnetic stripes continent material drilled core samples ocean water samples

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.

Which organelle in a eukaryotic cell is most noticeable under a microscope? nucleus nucleolus ribosome nuclear envelope