who determined that all animals are made of cells
Robert Hooke
title: Cell theory text: Cell theory In biology, cell theory is the historic scientific theory, now universally accepted, that living organisms are made up of cells, that they are the basic structural/organizational unit of all organisms, and that all cells come from pre-existing cells. Cells are the basic unit of structure in all organisms and also the basic unit of reproduction. With continual improvements made to microscopes over time, magnification technology advanced enough to discover cells in the 17th century. This discovery is largely attributed to Robert Hooke, and began the scientific study of cells, also known as cell biology. Over a century later, title: Cell (biology) text: contain more than 10 trillion (10) cells. Most plant and animal cells are visible only under a microscope, with dimensions between 1 and 100 micrometres. Cells were discovered by Robert Hooke in 1665, who named them for their resemblance to cells inhabited by Christian monks in a monastery. Cell theory, first developed in 1839 by Matthias Jakob Schleiden and Theodor Schwann, states that all organisms are composed of one or more cells, that cells are the fundamental unit of structure and function in all living organisms, and that all cells come from pre-existing cells. Cells emerged on Earth at least title: Cell theory text: types), compared with 10–20 in plants, fungi, and protoctista. Cell theory In biology, cell theory is the historic scientific theory, now universally accepted, that living organisms are made up of cells, that they are the basic structural/organizational unit of all organisms, and that all cells come from pre-existing cells. Cells are the basic unit of structure in all organisms and also the basic unit of reproduction. With continual improvements made to microscopes over time, magnification technology advanced enough to discover cells in the 17th century. This discovery is largely attributed to Robert Hooke, and began the scientific study of cells, title: Cell theory text: is no longer accepted with modern cell theory. In 1839, Theodor Schwann states that along with plants, animals are composed of cells or the product of cells in their structures. This was a major advancement in the field of biology since little was known about animal structure up to this point compared to plants. From these conclusions about plants and animals, two of the three tenets of cell theory were postulated. 1. All living organisms are composed of one or more cells 2. The cell is the most basic unit of life Schleiden's theory of free cell formation through crystallization title: Cell biology text: such as cancer, and other diseases. Research in cell biology is closely related to genetics, biochemistry, molecular biology, immunology and cytochemistry . Cells, which were once invisible to the naked eye, were first seen in 17th century Europe with the invention of the compound microscope. Robert Hooke was the first person to term the building block of all living organisms as "cells" after looking at cork. The cell theory states that all living things are made up of cells. The theory also states that both plants and animals are composed of cells which was confirmed by plant scientist, Matthias Schleiden