Build several models of his tree house out of different materials, and see which model holds up best to wind, water, and ice.
Answer:
The right answer for the blank is cleavage.
Explanation:
After fertilization the next step is cleavage in which zygote divide mitotically. As the embryo move from oviduct down the fallopian tube it divide into two cell and then four cells. four cell embryo is known as blastomere.
The periodic table only accounts for elements. It does not account for compounds, such as water.
This indicator is an estimate of the amount of space on the earth that an individual uses in order to survive using existing technology. This space includes the biologically productive land and water area that produces the resources consumed by that individual such as food, water, energy, clothing, and building materials. It also includes the amount of land and water required to assimilate the wastes generated by that person. In other words, the ecological footprint measures a person's demand on the bio-capacity of the Earth.