1. Basic Structure of a Cell

2. History of Cell Theory 1850 – Rudolf Virchow
mid 1600s – Anton van Leeuwenhoek
Improved microscope, observed many living cells
mid 1600s – Robert Hooke
Observed many cells including cork cells
Named the cell
1850 – Rudolf Virchow
Proposed that all cells come from existing cells

3. SCI.9-12.B [Indicator] - Recall the three major tenets of cell theory (all living things are composed of one or more cells; cells are the basic units of structure and function in living things; and all presently existing cells arose from previously existing cells).

4. SCI.9-12.B-2 - [Standard The student will demonstrate an understanding of the structure and function of cells and their organelles.]

5. *Cell Theory All organisms consist of 1 or more cells.
Cell is the smallest unit of life.
All cells come from pre-existing cells.

6. Observing Cells (4.1) Light microscope
Can observe living cells in true color
Magnification of up to ~1000x
Resolution ~ 0.2 microns – 0.5 microns

7. Observing Cells (4.1) Electron Microscopes
Preparation needed kills the cells
Images are black and white – may be colorized
Magnifcation up to ~100,000
Transmission electron microscope (TEM)
2-D image
Scanning electron microscope (SEM)
3-D image

8. SEM
TEM

9. *Introduction to Cells
Cells are the basic units of organisms
Cells can only be observed under microscope
Basic types of cells:
Bacterial Cell
Animal Cell
Plant Cell
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10. copyright cmassengale
*Number of Cells
Organisms may be:
Unicellular – composed of one cell
Multicellular- composed of many cells that may organize
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11. *Cells May be Prokaryotic or Eukaryotic
Prokaryotes include bacteria & lack a nucleus or membrane-bound structures called organelles
Eukaryotes include most other cells & have a nucleus and membrane-bound organelles (plants, fungi, & animals)

12. SCI.9-12.B [Indicator] - Compare the structures and organelles of prokaryotic and eukaryotic cells.

13. *Prokaryotes Nucleoid region contains the DNA
Cell membrane & cell wall
Contain ribosomes (no membrane) to make proteins in their cytoplasm
Only example is bacteria

14. *Eukaryotic Cell Contain 3 basic cell structures: Nucleus
Cell Membrane
Cytoplasm with organelles

15. Video clip about pro vs eu
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16. Two Main Types of Eukaryotic Cells
Animal Cell
Plant Cell

17. Organelles Very small size Can only be observed under a microscope
Have specific functions
Found throughout cytoplasm

18. How small is a cell?

19. SCI.9-12.B [Indicator] - Summarize the structures and functions of organelles found in a eukaryotic cell (including the nucleus, mitochondria, chloroplasts, lysosomes, vacuoles, ribosomes, endoplasmic reticulum [ER], Golgi apparatus, cilia, flagella, cell membrane, nuclear membrane, cell wall, and cytoplasm).

20. Nucleolus Chromatin Nuclear membrane CYTOSKELETON RIBOSOMES ROUGH ER
MITOCHONDRION
SMOOTH ER
CENTRIOLES
GOLGI BODY
LYSOSOME
PLASMA MEMBRANE
Fig. 4-15b, p.59

22. Organelles Found in Cells
Examples of Organelles include:
Endoplasmic reticulum (rough & smooth) – canals for movement
Golgi Bodies – wrap & export proteins
Nucleolus – makes ribosomes
Lysosomes – digests & gets rid of wastes
Ribosomes – makes proteins

23. *Golgi Bodies Stacks of flattened sacs
Have a shipping side & a receiving side
Receive & modify proteins made by ER
Transport vesicles with modified proteins pinch off the ends
Transport vesicle

24. *Lysosome Contain digestive enzymes
Break down food and worn out cell parts for cells
Programmed for cell death (lyse & release enzymes to break down & recycle cell parts)

25. *Control Organelle Nucleus Controls the normal activities of the cell
Contain the DNA
Bounded by a nuclear membrane
Contains chromosomes

26. More on the Nucleus Nucleus
Each cell has fixed number of chromosomes that carry genes
Genes control cell characteristics

27. *Nucleolus Cell may have 1 to 3 nucleoli Inside nucleus
Disappears when cell divides
Makes ribosomes that make proteins

28. SCI.9-12.B [Indicator] - Summarize the structures and functions of organelles found in a eukaryotic cell (including the nucleus, mitochondria, chloroplasts, lysosomes, vacuoles, ribosomes, endoplasmic reticulum [ER], Golgi apparatus, cilia, flagella, cell membrane, nuclear membrane, cell wall, and cytoplasm).

29. *Smooth & Rough Endoplasmic Reticulum
Smooth ER lacks ribosomes & makes lipids also detoxifies poisons from medicine and alcohol
Rough ER has ribosomes on its surface & makes proteins to EXPORT

30. Cell Powerhouse *Mitochondrion (mitochondria ) Rod shape
*Site of Cellular respiration

31. * Mitochondria Active cells like muscles have more mitochondria
*Burn sugars to produce energy ATP

33. Cytoskeleton

34. Cytoskeleton
A network of fibrous proteins that help maintain cell shape, support the cell and help with movement.

35. Cytoskeleton All are proteins Function Structure
gives cells internal organization, shape, and ability to move
Structure
Interconnected system of microtubules, microfilaments, and intermediate filaments (animal only)
All are proteins

36. Cilia and flagella - structures for cell movement

37. SCI.9-12.B [Indicator] - Summarize the structures and functions of organelles found in a eukaryotic cell (including the nucleus, mitochondria, chloroplasts, lysosomes, vacuoles, ribosomes, endoplasmic reticulum [ER], Golgi apparatus, cilia, flagella, cell membrane, nuclear membrane, cell wall, and cytoplasm).

38. *Cell or Plasma Membrane
Cell membrane
Living layer
Controls the movement of materials into and out of the cell
Selectively permeable

39. Read this!
Proteins and carbohydrates on the outside of cells give cells their “identity.” This lets the immune system know that the cells belong in that body. Transplanted organs are often rejected by the body because the immune system recognized the proteins and carbs as not belonging to that person’s body.

40. SCI.9-12.B [Indicator] - Summarize the structures and functions of organelles found in a eukaryotic cell (including the nucleus, mitochondria, chloroplasts, lysosomes, vacuoles, ribosomes, endoplasmic reticulum [ER], Golgi apparatus, cilia, flagella, cell membrane, nuclear membrane, cell wall, and cytoplasm).

41. Cytoplasm of a Cell Cytoplasm
Jelly-like substance enclosed by cell membrane
Provides a medium for chemical reactions to take place

42. *More on Cytoplasm Cytoplasm
Contains organelles to carry out specific jobs
Examples: chloroplast & mitochondrion