Answer:
B). Pollution and boat traffic
Explanation:
At the end of the esophagus is a thick ring of a muscle called a sphincter which allows food to enter the stomach but not from the stomach back into the esophagus. Once the food enters the stomach it is mixed with the digestive juices.
Answer:
As comic is not available, lets try to understand genetic drift generally.
Explanation:
Genetic drift can be described as the changes in the allele frequency or changes in the genotype variations of a population due to certain reasons such as death etc. In genetic drift, a particular genotype of a species starts to decrease, while the other genotype might start to increase. For example, imagine there are 6 colours of rabbits to be seen in a population. An event such as a diseases takes over which results in death of most of the rabbits. Only a few rabbits are left having brown and grey colour. Hence, the genetic drift changes from 6 to only 2.
DNA is the bio molecule that contains all of the organisms genes. when cell divides through mitosis, the daughter cells contains exact copies of DNA from both of its parents.
