Answer:
<em>The correct option is A) increase in atmospheric O2</em>
Explanation:
The nerve cells and the muscle cells suggest that the the presence of oxygen in the atmosphere was an adaptive radiation which brought the existence of different animals. The conditions became favorable for different animals to survive on Earth only when the availability of oxygen improved in the atmosphere. As animal cells like the muscle cells require a constant supply of oxygen, we can hence say that increase in atmospheric oxygen was the adaptive radiation for supporting many group of animals.
Answer:
Humans have about a thousand genes similar to those of bacteria ,because the genes are so vital that thier DNA structure has remained much the same over millions of years of decent from a common ancestor.
Explanation:
Answer:
Development
Explanation:
Development is the process that organisms undergo beginning with fertilization and continuing until an organism reaches maturity. It includes cell division and differentiation.
It involves progressive changes that occurs in an organism including a plant, animal or bacteria. Changes usually occur in shape, function and size throughout the life of the organism.
Examples of development is the metamorphosis of a tadpole to an adult frog or the metamorphosis if a larva to an adult insect or even the process of development from a fertilized egg all through to the maturation of a human.
Replication Fork! Is the answer! Hope this helps!
Trisomy 21 is the name for down syndrome
