10. Today I will:
Discuss the discovery of the cell and
the development of the cell theory;
Describe the unicellular and
multicellular cells; and
Realize the fruits of patience and
perseverance.
11. INSTRUCTION:
•Go to your respective groups for an
activity. Bring with you your lecture
notebook and ballpen.
12. Read the selection
“The Development of Cell
Theory”
and prepare for questions
that will be answered by
group.
13. •Have you ever seen a cell?
•When?
•What do you remember about
it?
14. •The cell is the smallest unit of matter that
can carry on all the processes of life.
•Most cells are visible only with a
microscope.
•Cells contain a variety of internal
structures called ORGANELLES.
15. According to the selection, who were
the pioneers in the discovery of cells
and what are their contributions?
16. ROBERT HOOKE
(1635 –1703)
An Englishman, he
coined the term “cell”
and was responsible for
introducing cytology as
a discipline in biology.
17. ANTON VAN
LEUWENHOEK (1632 –
1723)
A Dutch naturalist, he
discovered bacteria and
other microscopic
organisms in rainwater. He
studied the structure of
plant and animal cells.
18. ROBERT BROWN
(1773 – 1858)
A Scottish botanist,
he discovered the
presence of nuclei
within cells.
19. MATTHIAS SCHLEIDEN
(1804 – 1881) &
THEODOR SCHWANN
(1810 – 1882)
The German botanist
and zoologist,
respectively,
introduced the concept
that all plants and
animals are made up of
cells.
20. RUDOLF VIRCHOW
(1821 – 1902)
A German physician, he
found that cells divide to
form new cells. He
concluded that cells
come from preexisting
cells.
21. State the CELL
THEORY.
According to the cell theory, proposed over 150
years ago:
• All living things are composed of cells.
• All cells come from pre-existing cells.
• Cells are the fundamental (smallest) units of
life.
22. WHAT IS A UNICELLULAR?
Organisms that are
made-up of only one
cell.
23. WHAT IS A MULTICELLULAR?
Organisms that are
composed of
countless cells.
24. WHAT DO YOU THINK:
•Are cells alive?
•Why do you think this is true?
•Where are cells located in your
body?
26. ¼ Sheet of paper: Match column A
with column B. Write letters only.
Column A Column B
___16.Matthias Schleiden
___17. Robert Brown
___18. Rudolf Virchow
___19.Theodore Schwann
___20. Robert Hooke
a. discovered the nucleus.
b. concluded that plants are
composed of cells.
c. the first to use the term “cell”.
d. stated that animals are made up
of cells.
e. stated that all cells come from
pre-existing cells.