Watson and Crick's model allowed them to visualize all of the following except the molecular bonds of DNA. the sugar and phosphate component of the DNA molecule's surface. how the purines and pyrimidines fit together in a double helix. the antiparallel design of two strands of the DNA double helix. that DNA replication was semiconservative.

Watson and Crick's model did not allow visualizing any of the options given in the above question.

Explanation:

Only in 1951 did Francis Crick meet James Watson, initiating a partnership that two years later would be responsible for one of the most important discoveries in the biological sciences: together they devised the double helix model for the DNA molecule. In 1953, Watson and Crick presented a model compatible with the experimental results that had been obtained so far in other DNA studies. This model served as the basis for historical experiments that confirmed the initial hypothesis of these scientists.

The strategy employed by Watson and Crick was to build a molecular model that took into account the size and spatial configuration of nucleotides. Thus, through X-ray diffraction studies, Watson and Crick revealed that the DNA molecule is a compound made up of two long parallel strands, consisting of nucleotides arranged in sequence. However, the Watson and Crick model did not allow visualization of the molecular bonds of DNA, the sugar and phosphate component of the DNA molecule surface, as purines and pyrimidines fit into a double helix, the double strand antiparallel design of the double helix. DNA replication and that DNA replication was semi-conservative.