Viruses are not considered "alive" because they lack many of the properties that scientists associate with living organisms. Primarily, they lack the ability to reproduce without the aid of a host cell, and don't use the typical cell- division approach to replication.
Answer:
<em>The name for a complex group of organisms is system Hope this helps!</em>
The nucleaus controls everything within cells
The first step of DNA replication is the separation of the two DNA strands to create a replication bubble. DNA Helicase is what breaks the hydrogen bonds joining the two strands, allowing it to unravel.
The components that make up the cardiovascular system are....
The Heart.
The Arteries.
The Veins.
The Capillaries.
<em>Hope this helps</em>