Evolution of Cell Theory: Microscope Milestones & Cell Structures Revealed

1. Chapter 7 Cell Structure and Function

2. Section 7-1 The History of the Cell Theory and Microscopes

3. Historical View of the Cell Theory • As science improves, so do improvements in scientific instruments, and improved scientific instruments lead to new discoveries.

4. 1590 – Zacharias Janssen • Built first simple microscope (one set of lenses)

5. 1670’s Anton Van Leeuwenhoek • Made improvements • 270x magnification • Saw bacteria, protozoa, gametes, red blood cells and yeast cells.

6. 1665 – Robert Hooke • Produced a compound microscope • Saw hollow boxes and named them “cells”

7. 1665 – Robert Hooke

8. 1831 – Robert Brown • Saw central structure in plant cells, called this structure a nucleus

9. 1838 – Theodore Schwann • Concluded that all animals are made of cells

10. 1838 – Matthias Schleiden • Concluded that all plants are made of cells

11. 1839 – Johannes Purkinje • Stated that “the cell is the unit of function of life”

12. 1858 – Rudolf Virchow • Concluded that “ cells come only from previously existing cells”

13. The Cell Theory • All living things are composed of cells • Cells are the basic units of structure and function • New cells are produced from existing cells

14. Section 3-2 Prokaryotes and Eukaryotes

15. Eukaryotes • Have a nucleus and membrane covered organelles

16. Prokaryotes • Don’t have a nucleus and membrane covered organelles

18. Eukaryotic Cell Structures

19. Plasma Membrane • Separates the cell from its environment • Controls the transport of materials in and out • Allows some materials but not others to pass through this is called… • Selectively permeable

21. Endoplasmic Reticulum • Extensive network of tube-like structures that forms a passageway that functions in the transport of materials throughout the cells

23. Ribosomes • Site of protein synthesis • Attached to the walls of the ER or move freely in the cytoplasm

24. Golgi Bodies • Stack of tiny, flattened sac-like tubes used in secretion • Package protein molecules in a membrane and send the package to the cells surface

26. Mitochondria • Where cellular respiration takes place to release energy • “Mighty Mitochondria” • Powerhouse of the cell

28. Microtubules • Tubes that serve as support for the cell

30. Microfilaments • Thin threads attached to the cell membranes, play a role in movement

32. Lysosomes • Vesicles that contain enzymes used in digestion • Fuses with food vacuoles to digest food into smaller pieces • Digest old cell structures to dispose of them or even entire cells

35. Nucleus • Regulates all the cells activities

37. Chromosomes • Long coiled fibers that carry the material of heredity • Made of protein and DNA

39. Nucleolus • Composed of RNA • Involved in the passage of RNA into the cytoplasm

40. Centrioles • Small cylinders in the cytoplasm that play a role in cell division

42. Cilia

44. Flagella

46. Chloroplasts • Organelle found only in plants, used to make food

48. Vacuoles • Spherical, bubble-like storage sacs • Plant cells have very large vacuoles compared to animal cells

49. Cell Wall • Rigid structure that surrounds the cell membrane • Made of cellulose • Permits most things to pass through Cell Wall

50. Section 3-3 Cellular Processes