Answer:
what is the question? please let me know
Answer:
Either the cell wall or the cell membrane.
Explanation:
All cells have cell membranes which line the outside of the cell, and some cells have cell walls, which also line the outside of the cell. Since all cells have cell membranes I am inclined to believe that the correct answer would be cell membranes.
No genes make up chromosomes. Chromosomes contain DNA sequences and specific sequences aka genes make specific traits.
Answer:
The correct option is <u><em>A. they evolved from land mammals.</em></u>
Explanation:
The process of evolution explains how closely one organism is to another based on their common ancestors. Scientists believe that those organisms which show many similarities in their structures or functions might have evolved from a common ancestor in the past.
As in the above-mentioned question, scientists have observed that cetaceans lack gills and breath air, this is a property of land mammals. The cetaceans have fin bones which are similar to the limb bones. As limb bones are present in land mammals, hence they cetaceans and land mammals might have common ancestors in the past.
Every organism is unique, even though the nucleotides making up DNA are all the same, because the structure is different in every organism. In other words, it's just the order in which nucleotides are placed that differs each organism from one another.