Dolphins produce a variety of vocalizations, usually in the form of clicks and whistles. Dolphins are sometimes hunted in places like Japan, in an activity known as dolphin drive hunting. Besides drive hunting, they also face threats from bycatch, habitat loss, and marine pollution.
The DNA sequence of a gene can be altered in a number of ways. Gene mutations have varying effects on health, depending on where they occur and whether they alter the function of essential proteins. The types of mutations include:his type of mutation is a change in one DNA base pair that results in the substitution of one amino acid for another in the protein made by a gene.
A change to the DNA in a gene can alter a protein's amino acid sequence, thereby changing its shape and function and rendering the protein ineffective or even malignant (e.g. sickle cell anemia). Changes to genes are called mutations. single 'gene' is most similar to a single 'word' in the English language. The nucleotides (molecules) that make up genes can be seen as 'letters' in the English language. Nucleotides are named according to which of the four nitrogenous bases they contain. The four bases are cytosine, guanine, adenine, and thymine.