The presence of a membrane bound nucleus describes the evolution of eukaryotes from prokaryotic organisms. The endosymbiotic theory describes the same, the large cells engulfed the smaller ones, and the engulfed cells were not digested but started living in mutual cooperation with the engulfing cell. Mitochondria and chloroplast are thought to be the engulfed cell
Claim: No tools to discover the impending Cell Theory.
Reasoning:
Schleiden and Schwann, as well as Virchow, are generally seen as the founders of the cell theory, due to their pioneering scientific work in the 1800s. The unified cell theory states that: all living things are composed of one or more cells; the cell is the basic unit of life; and new cells arise from existing cells.
Evidence: The cell theory has many complexities and is of importance due to its affect to nearly every aspect of biology, from our comprehension of life & death, managing diseases, cycles and etc. But early scientists had no tools to study cells. They didn't even know about them. It took the invention of the microscope to view them and to begin an understanding of cells.
(Two Dutch spectacle-makers and father-and-son team, Hans and Zacharias Janssen, create the first microscope.) Matthias Schleiden observed that all plants were made of cells from the microscope and Theodor Schwann observed that all animals were also made of cells. Rudolf Virchow observed that cells only come from other cells Virchow saw cells dividing and added that living cells arise only from other living cells. These ideas led to cell theory, which states that all organisms are made of cells, all life functions occur in cells, and all cells come from other cells.
Amino acids because the monomer for proteins is “Amino Acids”
The answer is calcaneus (heel bone) :)
Osler's nodes are split pea–sized, erythematous, tender nodules located principally on the pads of the fingers and toes. They are few in number at any given time and occur in about 15% of patients with subacute bacterial endocarditis.
Hope this help if not so sorry
