This document provides an overview of cellular structures as observed through light and electron microscopy. It summarizes the appearance of organelles and other structures under different microscopy techniques, including the nucleus and nuclear pores, ribosomes and rough endoplasmic reticulum, Golgi apparatus, lysosomes, mitochondria, cytoskeleton components like microtubules and microfilaments, and the cell membrane and surface structures. Diagrams and electron micrographs are presented to illustrate these various intracellular components at both low and high magnification.

1. The Cell Observed by Light and Electron Microscopy

2. Overview of the Cellular Organelles

3. Light Microscopy – Hematoxylin & Eosin (H&E) Stain Basophilic (blue) Nuclei Eosinophilic (red) cytoplasm

4. Colorized low mag TEM of a cell Red = Mitos Blue = Ribos Green = RER

5. Colorized TEM of a cell nucleus Arrow = Nucleolus Red = Mitos Green = RER

6. Nuclear Structures

7. Low mag TEM of a nuclei

8. Nuclear pores (arrows) Nuclear pores (en face)

9. Colorized TEM of nuclear pores (blue) en face

10. High mag TEM of a nucleolus Pars fibrosa/granulosa (dense black) and fibrillar center (arrow)

11. TEM of interphase nuclei and a mitotic cell with condensed chromosomes (arrow)

12. Cytoplasmic Structures Ribosomes, RER and Glogi

13. Ribosomes by light microscopy = basophilic cytoplasm

14. TEMs of free ribosomes – 25 nm granules – in clusters called polysomes

15. Colorized TEM of polysomes (yellow highlighted)

16. Low mag TEM of rough endoplasmic reticulum (RER)

17. Colorized higher mag TEM of RER (green)

18. TEM of RER – arrows indicate cisternae

19. Low mag TEM of RER and Golgi (Go)

20. Colorized TEM of a Golgi system

21. TEM of a Golgi system

22. TEM of lysosomes (arrows) & a residual body Residual Body

23. Cytoplasmic inclusions by Light Microscopy Basophilic granules (top picture) Eosinophilic granules (bottom picture)

24. Mitochondria

25. Colorized TEM of Mitochrondria (red)

26. TEMs of Mitochrondrial shapes

27. TEM of a Mitochrondrion Arrows = cristae

28. The Cytoskeleton

29. Light microscopy of mitotic spindles = Microtubules

30. Colorized TEM of Cilia in cross section showing microtubules

31. Immunofluorescence of Microtubules in cultured cells (green)

32. TEM of Microfilaments (arrows)

33. Immunofluorescence of microfilament stress fibers in cultured cells

34. Cell Membrane

35. High mag TEM of two cell membranes (unit membrane)

36. Colorized TEM of two cell membranes (unit membrane)

37. TEMs of membrane specializations Top 4 = microvilli Middle = Stereo cilia Bottom = Cilia

38. TEM of Cilia (C) with microtubular cores forming from basal bodies (BB)

39. High mag TEM of Cilia with microtubular cores (Fil) with the basal body (FiC) at top of image