Final answer:
Casimir Funk conducted studies on rats to investigate the relationship between beriberi disease and brown rice. He discovered a complex of micronutrients that could cure beriberi and proposed the term 'vitamine' for these micronutrients. Funk's studies on rats contributed to our understanding of the role of nutrition in disease.
Step-by-step explanation:
Casimir Funk, a Polish-born biochemist, conducted studies on rats to understand the relationship between beriberi disease and brown rice. In 1912, Funk isolated a complex of micronutrients from rice bran and proposed that it could cure beriberi. He named this complex 'vitamine', which later became known as thiamine or vitamin B₁. Funk's studies on rats helped demonstrate the role of nutritional deficiencies in causing disease.