HRT-2020 Chapter : Chapter 1
Document Summary
4. 6 billion years!, know how many zeros: miracle around 4 billion years ago, living species were on planet, one. At some point, life must have spontaneously appeared on planet. From that life, first species on planet: today we have 100 million species on the plant-exam question, came up with the idea that if earth was spontaneously started, they could redo it in a lab and produce organisms. O2 and o3 were in trace amounts. there was carbon, hydrogen such. After a few days, the water based solution was no longer clear. What they did find was basic biological molecules. Simple building blocks that may after many years of the experiment produce nucleotides and carbs and proteins. Called cell theory-states that existing cells come from preexisting cells on the planet: 10" s of trillions of cells in the body. Started out as one cell: mitosis to divide cells.
