Answer:
in 1978, he discovered a 52-million-year-old skull in Pakistan that resembled fossils of creodonts
<span>If a scientist is trying to determine whether the use of cell phone contributes to brain cancer, then the most significant weakness in this type of study is the relationship between the cell phone and brain cancer itself. It is hard to identify its connections and consequences with each other.</span>
Answer:
Energy is released when new bonds form.
Explanation:
Bond-making is an exothermic process. Whether a reaction is endothermic or exothermic depends on the difference between the energy needed to break bonds and the energy released when new bonds form.
The yolk sac functions to form blood cells in early development (embryonic phase) for nourishment of the embryo and early fetus. Towards the end of the 1st trimester, the yolk sac disappears and the placenta takes over for the fetus.
During prophase, the chromosomes condense and the nucleolus disappears, and the nuclear envelope breaks down