I had always thought of cells as simple diagrams on the pages of textbooks. In biology, we learned what the different organelles and structures contained in the cell are called and what functions they perform. Yet, despite knowing that all living things are made up of cells, I never thought of cells as hectic and lively structures that vaguely resemble "vast, teeming metropolis[es]". The excerpt from Bryson's book describes cells as "hazardous place[s]" and organelles as "some [being] the size of basketballs, others the size of cars", comparing the cytoskeleton to a "complex framework of girders", and calling DNA "full-time occupants" of the cell. This view of the cell as a structure resembling a city bustling with life surprised me, and made me realize the complexity behind what all living organisms are composed of. The organelles and substances within the cell are shown to have many different "mundane" tasks, many of which are akin to jobs that humans have in a modern society, for example "getting rid of waste, warding off intruders, sending and receiving messages, [and] making repairs," and the degree of similarity between the basic units of structure that we're composed of and the interactions between us as humans is quite startling, and made me view cells in a completely different light than I had before.In the excerpt, Bryson starts off with a description of cells' miniature sizes, and how scientists overcame many difficulties in order to gain knowledge about them. He describes how Hooke was the first to identify cells which he saw as "little chambers in plants," how Leeuwenhoek, a simple "linen draper", was able to get "magnificent magnifications" in his examinations, and how Brown was discovered nuclei in atoms. He states that, at a molecular level, even water becomes a "kind of heavy-duty gel" and "a lipid is like iron." That made me wonder: if lipids have only 'the consistency of a "light grade of machine oil"', then what prevents the cells from being sliced open or popped whenever we hold something like metal or paper, substances that are evidently more rigid than lipids? Once I was convinced of how incomprehensibly small and inconceivably complex cells are, "too small to be seen, but roomy enough to hold thousands of complicated structures," Bryson astonished me yet again with the magnitude of what cells can do: our hearts "must pump..... 657,000 gallons a year--enough to fill four Olympic-sized swimming pools" just to keep our cells oxygenated. It's no wonder that red blood cells die every 120 days. They have to carry oxygen to the cells of our body when our bodies have such rigorous demands and require them to work so hard. The contrast between the microscopic size of cells and the many functions they perform to keep us alive hit me after reading this excerpt, and increased my appreciation of cells and what they do for us, changing my earlier belief that cells were simply another subject in biology instead of structures that play such monumental roles in keeping us alive.
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