General Biology

Romans

Discovered how to make glass in the 1st century BC, which helped create microscopes.

Theory

A set of principles developed over time via multiple investigations.

1665-1838

Years when microscopes improved and cells were first discovered.

What is Cell Theory?

Cell Theory is a fundamental principle in biology that describes the properties of cells and is composed of three major parts.

3 major parts of cell theory

1.All organisms are made of cells.

2.All existing cells are produced by other living

cells.

3.The cell is the most basic unit of life.

Robert Hooke

English scientist who used the compound microscope to observe cork.

What did Robert Hooke observe?

Cork made up of small, hollow compartments.

Origin of the Word "Cells"

Hooke thought the compartments looked like small rooms (cells) in a monastery, so he gave them that name.

Hooke’s Discovery

He discovered the cell in 1665, which started the formulation of the cell theory.

Anton van Leeuwenhoek

Dutch tradesman who studied new ways to make lenses for observing cloth.

Leeuwenhoek’s Microscope

His microscope was more powerful than Hooke’s compound microscope.

What did Leeuwenhoek observe with his microscope?

Single-celled organisms swimming in pond water.

What did Leeuwenhoek call these organisms?

Animalcules (tiny animals and plants).

Anton van Leeuwenhoek is known for

Being one of the first scientists to describe living cells.

Matthias Schleiden

German scientist fascinated with plant cells.

Schleiden’s Study

Used the compound microscope to examine plant cells.

Schleiden’s Discovery

all plant parts are made of cells.

Who did Schleiden discuss his findings with?

Theodor Schwann, his close friend and fellow scientist.

Theodor Schwann

German scientist who studied both plant and animal cells.

Schwann’s Discovery

Determined that all animals are made of cells.

similarities that Schwann noticed

Plant and animal cells share structural similarities.

Schwann’s Contribution

Published the first statement of the cell theory: all living things are made of cells and cell products.

Rudolf Virchow

Scientist who stated that all cells come from preexisting cells.

Virchow stated that

All cells come from preexisting cells.

Virchow’s Contribution

Completed the second part of the cell theory.

Cell Theory Formulation

After Virchow’s work, the cell theory was finally formulated in 1838.

sino ang papasa sa exam

tayo malamang hahahaha