zaman pertengahan dulu - masyarakat barat during the middle age / medieval amatlah jahil , setelah keruntuhan roman empire, dan selepas itu muncullah zaman renaissance - kelahiran semula...
okay dalam zaman ni - muncul teori spontanoeous generation - yg katanya non life elments cretae living organism...
so , kalau anda percaya , dan ada atheist percaya ini makanya tak lah advance pun pemikiran anda?
anda sama jah macam masyarakt barat from 5th - 15th century
It was once believed that life could come from nonliving things, such as mice from corn, flies from bovine manure, maggots from rotting meat, and fish from the mud of previously dry lakes. Spontaneous generation is the incorrect hypothesis that nonliving things are capable of producing life. Several experiments have been conducted to disprove spontaneous generation; a few of them are covered in the sections that follow.
Redi's Experiment and Needham's Rebuttal
In 1668, Francesco Redi, an Italian scientist, designed a scientific experiment to test the spontaneous creation of maggots by placing fresh meat in each of two different jars. One jar was left open; the other was covered with a cloth. Days later, the open jar contained maggots, whereas the covered jar contained no maggots. He did note that maggots were found on the exterior surface of the cloth that covered the jar. Redi successfully demonstrated that the maggots came from fly eggs and thereby helped to disprove spontaneous generation. Or so he thought.
In England, John Needham challenged Redi's findings by conducting an experiment in which he placed a broth, or “gravy,” into a bottle, heated the bottle to kill anything inside, then sealed it. Days later, he reported the presence of life in the broth and announced that life had been created from nonlife. In actuality, he did not heat it long enough to kill all the microbes.
Spallanzani's Experiment
Lazzaro Spallanzani, also an Italian scientist, reviewed both Redi's and Needham's data and experimental design and concluded that perhaps Needham's heating of the bottle did not kill everything inside. He constructed his own experiment by placing broth in each of two separate bottles, boiling the broth in both bottles, then sealing one bottle and leaving the other open. Days later, the unsealed bottle was teeming with small living things that he could observe more clearly with the newly invented microscope. The sealed bottle showed no signs of life. This certainly excluded spontaneous generation as a viable theory. Except it was noted by scientists of the day that Spallanzani had deprived the closed bottle of air, and it was thought that air was necessary for spontaneous generation. So although his experiment was successful, a strong rebuttal blunted his claims.
Bioterms
[size=0.9em]Pasteurization originally was the process of heating foodstuffs to kill harmful microorganisms before human consumption; now ultraviolet light, steam, pressure, and other methods are available to purify foods—in the name of Pasteur.
Pasteur's Experiment
Louis Pasteur, the notable French scientist, accepted the challenge to re-create the experiment and leave the system open to air. He subsequently designed several bottles with S-curved necks that were oriented downward so gravity would prevent access by airborne foreign materials. He placed a nutrient-enriched broth in one of the goose-neck bottles, boiled the broth inside the bottle, and observed no life in the jar for one year. He then broke off the top of the bottle, exposing it more directly to the air, and noted life-forms in the broth within days. He noted that as long as dust and other airborne particles were trapped in the S-shaped neck of the bottle, no life was created until this obstacle was removed. He reasoned that the contamination came from life-forms in the air. Pasteur finally convinced the learned world that even if exposed to air, life did not arise from nonlife.
tapi yang pasti, kalau tuhan benar2 wujud, Dia tak sebodo tuhan2 yang ada pada agama2 yang wujud sekarang ni
agama yang Tuhan sebenar cipta pon tak mungkin ada kecacatan macam yang dimiliki oleh agama2 yang sedia wujud sekarang.. agama itu panduan.. kalau panduan pon caca merba dan banyak percanggahan, maka itu bermaksud agama itu bukannya dari tuhan, tapi dari manusia
LOL , you bring nothing new to the table.
Kalo ko klaim yg Islam ada cacat cela , bagi examples
Cakap aje tak guna. Bagi bukti. Hanya org tak cukup akal aje mampu cakap tanpa bukti
zaman pertengahan dulu - masyarakat barat during the middle age / medieval amatlah ...
baca la tentang miller-urey experiment dan chemical evolution, kat situ baru tahu camne tindakbalas kimia bagi unsur yang simple boleh "hidup" dan menjadi lebih kompleks..
cer tengok "game of life" kat video bawah ni..
If you ask me , it is a regressive form of thinking wrapped in arrogance.
This might interest you :
5. Montmorillonite catalysis of Ribonucleic acid oligomer formation
The ability of montmorillonite to catalyse a reaction was first observed in the studies on the cyclization of 3′-nucleotides to 2′,3′-cyclic nucleotides (Ferris et al. 1986). The yield of the cyclic product was twice as high, when the reaction was performed in the presence of Zn2+-montmorillonite. This finding prompted our investigation of the formation of a phosphodiester bond between 5′-nucleotides using a carbodiimide (figure 6a; Ferris et al. 1989) and then with the phosphorimidazolides of nucleosides using Na+-montmorillonite as the catalyst. (figure 6b; Kebbekus 1988; Ferris & Ertem 1993b). The latter reaction resulted in the formation of 6–14 mers, in an aqueous, pH 8 solution, with the oligomer length dependent on the base present in the nucleotide (Ferris & Ertem 1993a; Ding et al. 1996; Kawamura & Ferris 1999). Kinetic studies of the reaction of ImpA revealed that the montmorillonite enhanced the rate constant for oligomer formation by about 100–1000 times over that for the hydrolysis of the imidazole-activating group (Kawamura & Ferris 1994).
Figure 6
Figure 6
(a) A carbodiimide condensing agent; (b) RNA monomer activated with imidazole; (c) a monomer activated with 1-methyladenine; (d) and a monomer activated with 2-methyl imidazole.
Changing the reaction conditions and the phosphate-activating group led to the formation of significantly longer oligomers. A ‘feeding reaction’, where the activated monomer is added daily to a 10 mer nucleic acid primer bound to montmorillonite, resulted in the addition of 30–40 mers to the primer in 12–14 days (figure 7; Ferris et al. 1996; Ferris 2002). Changing the phosphate-activating group from imidazole to 1-methyladenine (figure 6) resulted in the formation of 40–50 mers of A or U in 1–3 days without the need of a primer (Huang & Ferris 2003). These advances were important because they generated longer oligomers with the capability of storing more genetic information as well as having enhanced catalytic capability.
Figure 7
Figure 7
Elongation of a primer by the daily addition of the activated monomer ImpA for 12–14 days.
Na-montmorillonite prepared from Volclay by the titration method facilitates the self-condensation of ImpA, the 5'-phosphorimidazolide derivative of adenosine. As was shown by AE-HPLC analysis and selective enzymatic hydrolysis of products, oligo(A)s formed in this reaction are 10 monomer units long and contain 67% 3',5'-phosphodiester bonds (Ferris and Ertem, 1992a). Under the same reaction conditions, 5'-phosphorimidazolide derivatives of cytidine, uridine and guanosine also undergo self-condensation producing oligomers containing up to 12-14 monomer units for oligo(C)s to 6 monomer units for oligo(G)s. In oligo(C)s and oligo(U)s, 75-80% of the monomers are linked by 2',5'-phosphodiester bonds. Hexamer and higher oligomers isolated from synthetic oligo(C)s formed by montmorillonite catalysis, which contain both 3',5'- and 2',5'-linkages, serve as catalysts for the non-enzymatic template directed synthesis of oligo(G)s from activated monomer 2-MeImpG, guanosine 5'-phospho-2-methylimidazolide (Ertem and Ferris, 1996). Pentamer and higher oligomers containing exclusively 2',5'-linkages, which were isolated from the synthetic oligo(C)s, also serve as templates and produce oligo(G)s with both 2',5'- and 3',5'-phosphodiester bonds. Kinetic studies on montmorillonite catalyzed elongation rates of oligomers using the computer program SIMFIT demonstrated that the rate constants for the formation of oligo(A)s increased in the order of 2-mer < 3-mer < 4-mer ... < 7-mer (Kawamura and Ferris, 1994). A decameric primer, dA(pdA)8pA bound to montmorillonite was elongated to contain up to 50 monomer units by daily addition of activated monomer ImpA to the reaction mixture (Ferris, Hill and Orgel, 1996). Analysis of dimer fractions formed in the montmorillonite catalyzed reaction of binary and quaternary mixtures of ImpA, ImpC, 2-MeImpG and ImpU suggested that only a limited number of oligomers could have formed on the primitive Earth rather than equal amounts of all possible isomers (Ertem and Ferris, 2000). Formation of phosphodiester bonds between mononucleotides by montmorillonite catalysis is a fascinating discovery, and a significant step forward in efforts to find out how the first RNA-like oligomers might have formed in the course of chemical evolution. However, as has been pointed out in several publications, these systems should be regarded as models rather than a literal representation of prebiotic chemistry (Orgel, 1998; Joyce and Orgel, 1999; Schwartz, 1999).
3.5. Adsorption of nucleic acid bases by clay minerals
The adsorption of nucleic acid bases by montmorillonite has been widely investigated. Lawless et al. (1984) and Banin et al. (1984) reported that the adsorption of adenosine monophosphate (AMP) by montmorillonite, containing different exchangeable cations (Zn, Cu, Mn, Fe, Ca, Co, Ni), generally increased as solution pH decreased [33, 34]. In the case of Zn-montmorillonite, adsorption of 5’-AMP reached a maximum at pH ~7. The extent of adsorption was primarily influenced by the acid dissociation constant of the nucleic acid base. Winter and Zubay (1995) investigated the relative ability of montmorillonite and hydroxylapatite in adsorbing adenine and adenine-related compounds [35]. They found that montmorillonite adsorbed more adenine than the other compounds (adenosine, 5’-AMP, 5’-ADP, 5’-ATP), while hydroxylapatite preferred adenosine phosphate to adenine and adenosine. The extent of adsorption depended on solution pH, and might also be affected by the buffer used.
More recently, Hashizume et al. (2010) investigated the adsorption of adenine, cytosine, uracil, ribose, and phosphate by Mg-montmorillonite [36]. At comparable concentrations in the equilibrium solution, adsorption decreased in the order adenine > cytosine > uracil, while ribose was hardly adsorbed. Hashizume and Theng (2007) found that allophane had a greater affinity for 5’-AMP than for adenine, adenosine, or ribose [37]. Again, very little ribose was adsorbed. The strong adsorption of 5’-AMP accords with the high phosphate-retention capacity of allophane [38].
The adsorption of nucleic acid bases to clay mineral surfaces has also been assessed by computer simulation. An ab initio study by Michalkova et al. (2011) suggests that uracil was adsorbed perpendicularly to the kaolinite surface [39]. With montmorillonite, on the other hand, nucleic acid bases tend to adsorb in a face-to-face orientation with respect to the basal siloxane plane [40].
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