Scientists use fossils to learn about organisms' lives and evolutionary relationships, to understand geological change, and even to locate fossil fuel reserves.
Answer:
The KID protein is responsible for the no pigmentation at the juvenile stage. When the KID protein inhibits in the adult state, the pigmentation occurs in the body. This might occur because the KID protein acts as the repressor molecule and acts as a negative regulator of PIG protein.
The KID protein is responsible for pigmentation an adult stage. Any mutation in the KID gene might result in the loss of pigmentation in the adult. The KID gene is responsible for the binding of the KID protein and mutation in this gene can lead to the arrest of KID protein. The protein is unable to release and PIG continuously repressed in the adults.
Cellular differentiation describes how different cells perform different processes and have unique functions. There are at least 250 cells in the human body and each one plays a different role, and <em>all</em> of them are crucial to the body's ability to maintain homeostasis. For example, liver cells produce proteins that are important in blood clotting. If these cells are damaged, blood will not clot properly. If blood does not clot, a body cannot maintain homeostasis and the person will fall ill.
TL;DR: every cell plays its part and keeps the organism alive.
It is thought that life arose on earth around four billion years ago. The endosymbiotic theory states that some of the organelles in today's eukaryotic cells were once prokaryotic microbes.
