Illustration of Cell theory

1839 Cell theory

The book of science

Tom Sharp

Matthias Jakob Schleiden, Theodor Schwann, Barthélemy Charles Joseph Dumortier, Hugo von Mohl, Robert Remak, Rudolf Virchow cell biology Illustration of Cell theory

Cell theory

Schleiden said that plants are made of cells or of things that are made by cells. Schwann said that animals, too, are made of cells or of things that are made by cells. Schleiden thought that cells were formed spontaneously, like crystals, but Dumortier and von Mohl pointed out that cells with two nuclei were in the process of cell division. Subsequently, Remak, then Virchow claimed that cells are created only by cell division.

Factory prototype

The fact that each cell in your body contains your body’s complete instructions doesn’t mean that it’s easy. Fallen hairs and drops of spittle do not make little humans like yourself scattered all over your house. Bacteria, fungi, and pollens have an easier time, being simpler and able to survive on their own. The genetic code in each cell must be nurtured in a nuclear envelope, the nucleus, and surrounded by several other types of organelles. Membranes, pores, tubules, and vesicles, endoplasmic reticula, Golgi apparatuses, mitochondria, vacuoles, centrosomes, lysomes, and floating ribosomes make up millions of tiny biological factories that not only have a job to do but take care of their own maintenance and janitorial.


Every part of a mustard plant grows from a tiny seed. Every mustard seed grows from a mustard plant. Every moment of grace grows from a tiny hope. Every hope in every life grows from a moment of grace. Every moment in a life is like a mustard seed. Every life in every place may nurture a tiny hope.

Schleiden is accused of plagiarizing from Dumortier; Virchow is accused of plagiarizing from Remak. Wind-blown pollen, or a seed carried by the wind can result in a discovery, and it’s not always easy to tell if it had been discovered before.

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