Alexander Fleming is the answer ;D
<span>Most of the nitrogen gas in Earth's atmosphere comes from _____.
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D. the breakdown of carbon dioxide</span>
Multi cellular colonies of plant cells adhere to each other primarily by cell walls, whereas multi cellular colonies of animal cells are typically held together by proteins
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Explanation:</u></h3>
The organisms that contains more than single single are called as multi cellular organisms. They are just opposite to the uni cellular organisms. When many identical organisms groups to form together it is called as colonies.
It will be difficult in removing any organisms that forms colonies with the multi cellular organisms.The multi cellular organism of the cells in the plants are bonded to each other with the help of the cells walls. In animal cells these are bounded together with the help of the proteins.
No generations or hybrid would form before meselson and stahl would have observed evidence of a band in the cscl gradient.
The conservative model predicts that, following a single replication, half of the newly formed DNA double helices will be made entirely of the original, or old, DNA, and the other half will be entirely new. Then, each double helix would be completely replicated during the second round of replication. After that, 25% of the double helices would be all new, and 25% would be entirely old. Thus, the fraction of entirely new DNA double helices would increase with each succeeding round of replication, but the total number of completely unique DNA double helices would remain constant. Therefore, no hybrid DNA molecule containing 14N and 15N is replicated in the conservative model.
To learn more about conservative model. Click, brainly.com/question/14025877
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