1 Blood Cells: The most common types of blood cells are:  red blood cells (erythrocytes). The main function of red blood cells is to collect oxygen in the lungs and deliver it through the blood to the body tissues. Gas exchange is carried out by simple diffusion.
Rutherford and Bohr describe atomic structure1913. Photo: Niels Bohr's research notes for his new atomic theory. In 1911, Niels Bohr earned his PhD in Denmark with a dissertation on the electron theory of metals. Right afterwards, he went to England to study with J.J. Thomson, who had discovered the electron in 1897.
John Dalton. Best-known for his work in modern atomic theory, John Dalton was an English chemist, meteorologist and physicist. The son of a weaver, Dalton's major contribution to the field of chemistry is his atomic theory proposed in 1803.In the theory he reasoned that tiny particles called atoms make up elements.Early beginnings Though he came from a family of shoemakers and weavers, Dalton earned his living as a lecturer.n fact, it was Dalton's work in this field that turned what was considered by many to be folklore into a respectable science. Dalton's atomic theory In his famous atomic theory, Dalton stated that tiny particles called atoms form elements. Different elements would have atoms of different sizes and mass.