Origin of the cell by Andrea Cabral Sanchez https://padlet.com/andreacabral2/pwcbg7vw53qekbwr en-us 2023-04-28 16:19:56 UTC 2025-11-14 00:10:54 UTC hello@padlet.com Aristotle Theory - (350 b.c.) andreacabral2 https://padlet.com/andreacabral2/pwcbg7vw53qekbwr/wish/2572021045 Bugs born from dew drops on the leaves]]> 2023-04-28 16:32:46 UTC https://padlet.com/andreacabral2/pwcbg7vw53qekbwr/wish/2572021045 Theoprastus - (370 b.c.) andreacabral2 https://padlet.com/andreacabral2/pwcbg7vw53qekbwr/wish/2572028713 The Silphium plant sprouts  from the bare ground ]]> 2023-04-28 16:40:10 UTC https://padlet.com/andreacabral2/pwcbg7vw53qekbwr/wish/2572028713 Paracelsus - (1493) andreacabral2 https://padlet.com/andreacabral2/pwcbg7vw53qekbwr/wish/2572031980 Mice, toads and cells can be created from water, air, or decaying matter. ]]> 2023-04-28 16:43:17 UTC https://padlet.com/andreacabral2/pwcbg7vw53qekbwr/wish/2572031980 Francesco Redi - (1668) andreacabral2 https://padlet.com/andreacabral2/pwcbg7vw53qekbwr/wish/2572096630 Experiment in which two pieces of meat were put in two different jars. One of the jars was left uncovered and the other was covered with gauze to prevent flies from reaching the meat. After some time, it was observed that the meat in the uncovered jar had attracted worms, while the meat in the jar covered by the gauze had no worms.]]> 2023-04-28 17:48:39 UTC https://padlet.com/andreacabral2/pwcbg7vw53qekbwr/wish/2572096630 Lazzaro Spallanzani - (1729-1799) andreacabral2 https://padlet.com/andreacabral2/pwcbg7vw53qekbwr/wish/2572118846 He used nutrient-rich broth to observe microbial growth and found that the broth became cloudy due to microbial growth, unless it was sterilized and sealed. Spallanzani boiled the nutrient broth and observed that the covered boiled broth did not become cloudy, while the uncovered boiled broth did become cloudy, indicating the presence of microorganisms in the air. ]]> 2023-04-28 18:12:41 UTC https://padlet.com/andreacabral2/pwcbg7vw53qekbwr/wish/2572118846 Luis Pasteur - (1822-1895) andreacabral2 https://padlet.com/andreacabral2/pwcbg7vw53qekbwr/wish/2572125244 Pasteur disproved the widely held belief in the spontaneous generation of life. In a simple experiment using a sterilized flask with a bent neck, he showed that plain air cannot initiate the growth of microorganisms. A culture can grow in the flask only if germs enter it.]]> 2023-04-28 18:19:11 UTC https://padlet.com/andreacabral2/pwcbg7vw53qekbwr/wish/2572125244 Miller and Urrey - (1952) andreacabral2 https://padlet.com/andreacabral2/pwcbg7vw53qekbwr/wish/2572352467 Hypotheses:
1.
The production of Carbon compounds like sugars and amino acids:
Scientists passed vapor through a mix of     Methane (CH4), Hydrogen (H2) and Ammonia (NH3), to represent atmospheric gases from the beginnings of the earth.  They used electric discharges as a source of energy. Amino acids were formed and other carbon compounds necessary for life.    Amino acids are the basic units of proteins. 
2. 

Assembly of carbon compounds into polymers.

The assembly of  carbon compounds into polymers requires a source of energy.   

 A possible site for the origin of the first carbon compounds is around deep-sea vents. These are cracks in the Earth's surface, characterized by gushing hot water carrying reduced inorganic chemicals such as iron sulphide. These chemicals represent readily accessible supplies of energy. 

3.

Formation of membranes.

If phospholipids or other amphipathic carbon compounds were among the first carbon compounds, they would have naturally assembled into bilayers. Experiments have shown that these bilayers readily form vesicles resembling the plasma membrane of a small cell. This would have allowed different internal chemistry from that of the surroundings to develop. 


4.

  • In the early  phases of evolution…the RNA was the genetic material, and it could keep the same information as the actual DNA does. 

  • The ARN could auto replicate and also could act as an enzyme (catalyzer).


]]> 2023-04-29 02:24:36 UTC https://padlet.com/andreacabral2/pwcbg7vw53qekbwr/wish/2572352467 Assembly of carbon compounds into polymers - (1953) andreacabral2 https://padlet.com/andreacabral2/pwcbg7vw53qekbwr/wish/2572355516 The assembly of  carbon compounds into polymers requires a source of energy.    A possible site for the origin of the first carbon compounds is around deep-sea vents. These are cracks in the Earth's surface, characterized by gushing hot water carrying reduced inorganic chemicals such as iron sulphide. These chemicals represent readily accessible supplies of energy. ]]> 2023-04-29 02:34:55 UTC https://padlet.com/andreacabral2/pwcbg7vw53qekbwr/wish/2572355516 Endosymbiosis - (1960s) andreacabral2 https://padlet.com/andreacabral2/pwcbg7vw53qekbwr/wish/2572356850 The endosymbiotic theory sustains:

  • The mitochondrion  was a free prokaryote that developed the respiration process. 

  • The mitochondrion where “eaten” by prokaryotes thru the process of endocytosis and instead of digesting them, they live inside their hostage cytoplasm. 

  • The mitochondrion and the prokaryote organism had a symbiotic relationship helped by each other (mutualism).

  • The natural selection favored this kind of cells.   

  • This theory also explains the formation of chloroplasts. 
]]> 2023-04-29 02:38:45 UTC https://padlet.com/andreacabral2/pwcbg7vw53qekbwr/wish/2572356850 References andreacabral2 https://padlet.com/andreacabral2/pwcbg7vw53qekbwr/wish/2572358576 Libretexts. (2023). 1.3: The Myth of Spontaneous Generation. Biology LibreTexts. https://bio.libretexts.org/Bookshelves/Microbiology/Microbiology_Laboratory_Manual_(Hartline)/01%3A_Labs/1.03%3A_The_Myth_of_Spontaneous_Generation
Yo. (2022). Resumen del experimento de Francesco Redi sobre la generación espontánea - Celebérrima.com. celeberrima.com. https://www.celeberrima.com/resumen-del-experimento-de-francesco-redi-sobre-la-generacion-espontanea/
Louis Pasteur. by Brig Klyce. (s. f.). https://www.panspermia.org/pasteur.htm#:~:text=As%20for%20theoretical%20significance%2C%20Pasteur%20disproved%20the%20widely,in%20the%20flask%20only%20if%20germs%20enter%20it.
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