Answer:
The atomic model is our understanding of how the atom is structured. At one point in history, people believed that any substance was simply made of that substance and would retain that property no matter how small a quantity it was reduced to. Later, some argued that all matter was made of tiny particles called atoms. While this is correct, later researchers found that even the atoms were made of smaller particles called electron, protons, and neutrons. More recently, scientists have discovered quarks, tiny particles that makeup protons and neutrons.
To reproduce (asexually). Most unicellular organisms only live for mere hours. The best bet for the species to survive and thrive as a whole is for them to reproduce, or replicate.
Answer:
Option 4 - Calcium
Explanation:
The <em>divalent cation </em>called <em>calcium</em> is needed to provide additional support to the bone matrix.
Calcium is considered one of the most <em>important components</em> in bone development. It helps in the formation as well as maintenance of bone. During the modeling and remodeling process of bones, calcium facilitates the formation of <em>semi-hard new tissues</em> which leads to the formation of new bone which is very hard.
Due to this reason, calcium is needed to create extra bone matrix support.
The correct answer is D. Tortoises and snails have analogous organs, and they don't belong to the same species.
