Answer:
Genetic variation in a group of organisms enables some organisms to survive better than others in the environment in which they live. Organisms of even a small population can differ strikingly in terms of how well suited they are for life in a certain environment.
Explanation:
Genetic variations are important because a diverse gene pool is good for long-term survival of a species since the environment is always changing, so the diversity of DNA offers the most fit of the species a better chance of surviving because they are most adapted to the constantly changing environment.
The answer could be either B or D. Both are important for marine biology. I would have to say D is the best answer though!
It is transplanted routinely to treat a variety of blood and bone marrow diseases, blood cancers, and immune disorders. More recently, stem cells from the blood stream (called peripheral blood stem cells) and umbilical cord stem cells have been used to treat some of the same blood-based diseases
The saliva has enzymes that start to break down food using the lock and key system.The teeth chews the food and begins mechanical break down of food