What are motor skills? You might hear about the development of fine and gross motor skills in the pediatricianâs office, parenting magazines or a baby development book. What exactly are they? This is actually a pretty complicated question.
The cell was first discovered by Robert Hooke in 1665 using a microscope. The first cell theory is credited to the work of Theodor Schwann and Matthias Jakob Schleiden in the 1830s. In this theory the internal contents of cells were called protoplasm and described as a jelly-like substance, sometimes called living jelly.
Hi there. The cell membrane was discovered by Swiss botanist Carl Naegeli and C. Cramer in 1855. For about 200 years after the microscope was discovered, no one thought the cell membrane existed as they could only see the cell wall. Eventually though, It was discovered that there had to be some sort of extra covering in the cells.