1. Summarize how Anton van Leeuwenhoek, Robert Hooke, Matthias Schleiden and Theodore Schwann contributed to the study of cell biology.
Anton van Leeuwenhoek, a Dutch linen merchant, invented the microscope that magnified objects up to 300x. About the same time Leeuwenhoek was making his observations in Holland, Robert Hooke, an English scientist, looked at a thin piece of cork through his own microscope, and saw tiny boxlike compartments of it, which reminded him of a honeycomb. He described the boxes as cellulae, which has now given us our present-day word, cell. In 1839, Matthias Schleidon, a German botanist, and Theodore Schwann, a German zoologist, combined their observations and made the hypothesis that all organisms are composed of cells. They, along with the German scientist Rudolf Virchow, made general statements about living things and later formed a set of hypotheses called the Cell Theory.
2. What does spontaneous generation mean?
Spontaneous generation means that living organisms, could be produced from non-living matter such as air or water. This idea was used to explain such observations as maggots appearing suddenly in decaying carcasses.
3. Explain how Francesco Redi’s experiment disproved
Redi placed rotting meet in two experimental jars and two control jars. He used the control jars to ensure accurate results. He placed a cloth over the experimental jars of rotting meat. He did not believe in spontaneous generation, but believed that only flies could produce more flies. Over time, because Redi had covered the experimental jars with the cloth, the flies settled into the control jars. They laid eggs and the maggots and flies filled the control jars while the experimental jars were empty. This proved that maggots were produced only after eggs were laid and not by spontaneous generation.
4. In the 1700s, people used to say that they “suffered
from the vapours” if they felt unwell. What...