1. AIM: How do we describe cells?
TOPIC: CELLS
AIM: How do we describe cells?

2. How do we know that cells exist?
The discovery of the microscope

3. Robert
Hooke
Observed slices of cork with a comp. microscope (1600’s)

4. Anton van
Leeuwenhoek
1600’s
Used a simple microscope
First to look at living cells

6. Observed one- celled organisms like bacteria
Rain pond water, the mouth, intestines

7. Matthias
Schleidan
Observed plant cells
All plants are made of cells

8. Theodor
Schwann
Observed animal cells
All animals are made of cells

9. Robert Virchow All cells are made from pre-existing cells.
(Cells divide  more cells)

10. Cell
Theory
1. Cells are the basic unit of structure in all living things.
(Living things are made of cells)

11. 2. Cells are the basic unit of function of all living things
(They carry out life processes)
3. All cells come from pre-existing cells.

13. 1. Viruses are NOT cells, and are NOT made of cells.
Exceptions
to the
Cell
Theory
1. Viruses are NOT cells, and are NOT made of cells.

14. Virus do not reproduce by division because they are not cells.

15. 2. Mitochondria & Chloroplasts
cell parts that have their own DNA and reproduce on their own.
(Don’t need the nucleus to reproduce)

17. 3. The first cell could not have come from a pre-existing cell.

18. Cells Microscopic Found in living things There are different types
Smallest living thing on earth

19. EXAMPLES OF CELLS
Skin cells
Bone cells

20. MORE CELLS
Brain cells
Blood cells

21. If there are so many cells how do we classify them?
Based on location or function of the cell
blood cell
muscle cell
If there are so many cells how do we classify them?
2.Based on the type of organism it belongs to
Plant cell
Animal cell

22. Any living thing
Examples:
Shark -Tree
-Bacteria
Human
-Bird
Organism

23. Nucleus or No Nucleus?? EUKARYOTES
Some cells have a nucleus, they are called
EUKARYOTES
(Hey, you!! Do you have a nucleus?)
Animal and Plant cells are eukaryotes.
Some cells don’t have a nucleus, they are called PROKARYOTES
Bacteria are prokaryotic cells.

24. Organelles they contain organelles
Cells work (perform life activities) because
they contain organelles
Structures that are found in the cell that perform all cell activities
a.k.a cell parts
Organelles

25. Examples of organelles
Nucleus
Located in the center of the cell
Appears as a circle
Sometimes solid in color
The function is to be the control center for the cell and contains chromosomes. Contains a Nucleolus – helps in protein production. Chromosomes - contain hereditary genetic information

26. Cell Membrane Located around the entire cell Appears as a thin line
Similar to the walls of the classroom
The function is to be a barrier (wall) between the outside of the cell and the inside. AND……
Allows materials to transport in and out of the cell

27. Cytoplasm Located inside the cell membrane and outside the nucleus
Appears as the “liquid” between all the organelles
The function is to support all the organelles AND…
Transport materials around the cell
Similar to the ______in our bodies

28. Vacuole Location is scattered around the cytoplasm
Appears as an empty circle
Vacuole
The function is to be the storage site for wastes and other cellular materials
Similar to the garbage pails in each room

29. Endoplasmic Reticulum
Located around the nucleus
Appears as canals
A.k.a. – ER
The function of the ER is to transport materials within the cell
AND….
Sometimes contains ribosomes

30. Ribosomes Located on the ER and scattered around the cytoplasm
Appears as dots
The function is protein formation (synthesis)
RIBosomes---Baby-back ribs give you protein

31. What do cells need to do all this work?
Mitochondria
Located within the cytoplasm
Appear as bean shaped structures
The function is the production of energy
A.k.a – the powerhouse

32. More Organelles Golgi Bodies Located in the cytoplasm
Appear as a structure with many folds
The function is to package all the wastes for removal

33. Lysosome Located in the cytoplasm
Appear as small circular structures with particles inside
The function is to digest (break down) cellular materials

34. Centriole Located in the cytoplasm Often near the nucleus
Appears in a set of two
ONLY IN ANIMAL CELLS
Centriole
The function is to help the cell with cellular division of the chromosomes

35. Chloroplasts The function is to perform photosynthesis
                                                   
                                                   
Located around the edge of the cell
Appear as oval structures with lines
ONLY IN PLANT CELLS
Contain Chlorophyll
Chloroplasts
The function is to perform photosynthesis
Photosynthesis
process in which plants
produce their own food

36. Cell wall Located outside the cell membrane ONLY IN PLANT CELLS
The function is to provide support and structure for the cell

37. Organelle Challenge