In DNA the sugar used is called deoxyribose whereas in RNA the sugar is ribose (hence DNA and RNA). The important structural difference between the two types of RNA is that mRNA takes on the shape of a line whereas tRNA has a clover-like shape.
A. Immune system
It helps our bodies fight everything that comes in our path.
Answer:
Gradually, as generations of elephants continued to selectively use and develop their trunks.
Explanation:
Jean-Baptiste Lamarck was famous French Naturalist. He was a soldier, a biologist and an academic. He gave an early theory of evolution known as the theory of Lamarckism.
It was Lamarck who first believed that elephants earlier had small trunks. But eventual when there was scarcity of food and water, the elephants stretched out its trunk to reached out for food such as trees and also water. And as a result their offspring inherited long and powerful trunk.
In his theory of Lamarckism, he believed that the species passes on its traits to the offspring which they acquired through their use in their lifetime. In this case, the elephants might have used their trunks in such a way that they became long and strong over time and they passed tis trait to their babies.
Vestigial structures are often homologous to structures that are functioning normally in other species. Therefore, vestigial structures can be considered the evidence for evolution, the process by which beneficial heritable traits arise in populations over an extended period of time.
