"scientific knowledge builds upon previous knowledge." which situation best illustrates the statement? a) repeating the experiment of another scientist. b) tina ignoring non-supportive results of an experiment. c) the development of the modern cell theory over the course of hundreds of years. d) tim classifying his experiment a failure because his results do not support his hypothesis.

The answer is C. This is because the discovery of the cell and its organelles began with the discovery of the microscope in the 17th century. As powerful microscopes were developed over time, the cell organelle become discover-able by different scientists. As other developments emerged, they enabled tagging of elements, hence monitoring of biochemical pathways also became possible.

during the process of dna replication, brdu can replace thymidine and incorporate into the newly synthesized dna, cell proliferation thus can be reflected in the extent of brdu incorporation.

answer: ice crystals in air

the water from the water body or another source of water gets evaporated as water vapor as an effect of heat on water. these water vapor rises in the upper layers of the earth atmosphere under high atmospheric pressure. the atmospheric pressure of these water molecules starts to decrease due to the effect of cold air. the invisible water vapor condenses into visible water droplets and ice crystals.these ice crystals and water droplets being less denser than the surrounding air floats on air as clouds.