1. …..as units of Life. Ch. 7.1 A View of the Cell
CELLS
…..as units of Life.
Ch. 7.1 A View of the Cell

2. CELLS
Basic units of:
Structure and
Function of all living things.

3. STRUCTURE= HOW IT IS BUILT/CONSTRUCTED.
FUNCTION= WHAT IT DOES, HOW IT WORKS.

4. Some Random Cell Facts
The average human being is composed of around 100 Trillion individual cells!!!
It would take as many as 50 cells to cover the area of a dot on the letter “i”

5. People who led to cell discovery
1665- English Scientist, Robert Hooke, discovered cells while looking at a thin slice of cork.
He described the cells as tiny boxes or a honeycomb “boxlike structures”
He thought that cells only existed in plants and fungi

6. Hooke named these tiny compartments “cells” as they resembled a monk’s chamber. Observed cork cells at 30X magnification

7. Anton van Leuwenhoek
1673- Used a handmade microscope to observe pond scum & discovered single-celled organisms
He called them “animalcules” (little animals)
He also observed blood cells from fish, birds, frogs, dogs, and humans
Therefore, it was known that cells are found in animals as well as plants

8. Development of Cell Theory
1838- German Botanist, Matthias Schleiden, concluded that all plant parts are made of cells
1839- German physiologist, Theodor Schwann, who was a close friend of Schleiden, stated that all animal tissues are composed of cells. TOGETHER they concluded “all plants and animals are made of cells”.
Schwann

9. Development of Cell Theory
1858- Rudolf Virchow, German physician, after extensive study of cellular pathology, concluded that “all cells must arise from preexisting cells.”

10. Development of Cell Theory
Robert Brown – discovered the cell nucleus.
Henri Dutrochet – said all living things are composed of cells.

11. The Cell Theory:
All organisms are composed of one or more cells
All cells carry on “life processes”
All cells come from pre-exiting cells

12. Modern Cell Theory
Modern Cell Theory contains 4 statements, in addition to the original Cell Theory:
1) The cell contains hereditary information(DNA) which is passed on from cell to cell during cell division.
2) All cells are basically the same in chemical composition and metabolic activities.
3) All basic chemical & physiological functions are carried out inside the cells.(movement, digestion,etc)
4) Cell activity depends on the activities of sub-cellular structures within the cell(organelles, nucleus, plasma membrane)

13. How Has The Cell Theory Been Used?
The basic discovered truths about cells, listed in the Cell Theory, are the basis for things such as:
Disease/Health/Medical Research and Cures(AIDS, Cancer, Vaccines, Cloning, Stem Cell Research, etc.)

14. Two basic cell types: Prokaryotic & Eukayotic
An Organelle Is:
A minute structure within a plant or animal cell that has a particular job or function.

15. Prokaryotic cells pro = no
1)Earliest cells
2)Lack membrane bound organelles (none)
3)No nucleus
4)No mitochondria
5)Have cell wall, cytoplasm & free DNA

16. Prokayrotic cells: Bacteria

18. Eukaryotic cells: Eu = true
1)May have evolved from Prokaryotic
2)Have a nucleus that holds the DNA inside a membrane
3)Have mitochondria
4)Also have cell membrane & cytoplasm

19. What are some differences between animal and plant cells?
Nucleus
Mitochondria
ANIMAL PLANT

20. Human muscle cells
With large nuclei

21. Eukaryotic Cells: are found in animals like Paramecium
Nucleus
With DNA
For reproduction

22. The power house of the cell:
Mitochondria = where energy is released
Has a membrane like
The nucleus
ATP

23. Exception:
A Eukaryotic Cell
With NO NUCLEUS !

24. What are some differences between animal and plant cells?
ANIMAL PLANT

25. Organelles found only in Plants:
Cell Walls
Cellulose
Chloroplasts

26. Cell wall
Chloroplast
Large
vacuole
PLANT CELL

27. Both plants & protists have: chloroplasts cell walls cellulose
Plant cells
Both plants & protists have:
chloroplasts cell walls cellulose

28. No Wall, Just a Cell Membrane
Animal Cell

29. Organelles found only in Animal cells:
Centrioles = involved in cell division

30. Some Parting Thoughts
It is amazing to think that the cells that make up our bodies are just as alive as we are. Humans are just an intricately designed community of cells, which must work together to survive.