Sara just found out that her sister conceived about seven days ago. She rushes to find a book on pregnancy so that she can learn more about it. The book says that around the seventh day of pregnancy the cells of the zygote begin to:

Which of the following statements is true? 1. the mantle of the earth is made of solid nickel and iron. 2. the crust of the earth is made of solid nickel and iron. 3. the inner core is made of solid nickel and iron.

Which ideas did your answer contain? check all that apply. no food for organisms no oxygen in the atmosphere no trees or flowering plants no products based on trees or plants (building materials, medicines, fuels, fibers) no fossil fuels

According to the cladogram, which organisms have roundworms as a common ancestor?