Theodor Schwann(1810-1882)
A German physician and physiologist
who:
Theorized that animals are developed
from cells that divide into new cells.
Therefore, all animals are built from
dividing cells just like plants.
EXPERIMENT
In his experiment, he exposed sterilized
broth to heated air in a test tube. The
results showed that no microorganisms
were detected, and no chemical changes
occurred within the broth; therefore,
allowing him to conclude that the idea
of spontaneous generation is false.
Friedrich Gustav Jacob Henle
(1809-1885)
He was a German physician and pathologist
who made significant contributions to the
understanding of contagious diseases.
In his paper(1840), he embraced the
unpopular “microorganism theory of
contagion” put forth by the Renaissance
forerunner of modern epidemiology.
Cell Theory and Infectious
Diseases
Henle, along with his
contemporary Theodor
Schwann, contributed to the
formulation and acceptance of
the cell theory, which proposed
that the basic unit of life is the
cell. This laid the foundation
for understanding the role of
cells in infectious diseases.
Postulates
1. The agent must be
demonstrable in every case of
the disease.
2. The agent is not present in
other diseases
3. After isolation in culture, the
agent must be able to produce
the disease in experimental
animals
4. The agent can be recovered
from the experimental animal.