You are studying the development of a poorly-understood marine species. Watching an embryo develop, you see asymmetric cleavage and what appear to be protein granules apportioning to a few of the cells. Your labmate suggests pinching the embryos in half, so you have twice as many animals for your next experiment. Do you follow his advice?Multiple ChoiceNo -- this would result in twins, but they would be smaller and less healthy.No -- this would result in deformed embryos, since this species does not appear to have regulative development.Yes -- separating the blastomeres should result in two identical twins.Maybe -- it would depend whether the egg has large amounts of yolk to support two embryos.

In the early stages of vertebrate development, the process of cleavage yields successive blastomeres. How are these blastomeres described?Multiple choice question.They grow larger and larger.They begin cellular differentiation immediately.They become smaller and smaller.They are about the same size as the original zygote.

Which is a true statement about regulative development?Multiple ChoiceEarly blastomeres are committed to the development of a specific type of tissue.If an embryo splits in two, identical twins result.Body form is determined by cell fates genetically predetermined in each cell.Only invertebrates exhibit regulative development.

If the cells of the morula or the inner cell mass split, what type of twins will develop?Multiple choice question.FraternalDoubleConjoinedIdentical

Looking at the outside of a mammalian blastocyst, some of the cells that you see will become what extraembryonic structure?Multiple Choiceectodermendodermmesodermplacenta

What is the normal result if more than one egg is fertilized and there are multiple zygotes?