Answer:
Both fish and bird embryos exhibit gill slits and a tail.
Explanation:
According to embryology, all vertebrates exhibit similar traits and structures at their embryonic stage. It becomes very difficult to differentiate between the embryos of a fish, and that of a bird, or embryo of a fish, and a human. These traits, however, disappear, as the case may be, as the embryo develops into an adult. For example, in the case of the embryo of a fish, and a bird, both shows gills slits at their respective embryonic stage. However, the gill slits in fish develop into gills, whereas in the case of birds, it disappears as the embryo develops into an adult.
When the surface water is heated by the sun it dissolves more salt i believe
The atria of the heart merely need to allow blood to flow into the ventricle, and therefore aren't very muscular.
The ventricles of the heart need to actually pump blood to the rest of the body, whether to the lungs or the the rest of the body.
True but to be exact its 40,075