1. Chapter 1
Cell Structure

2. Cellular Organization
Cell- compartmentalization
Tissue
Organ
Organ System
Organism

3. How do people get sick?

4. Redi and Spontaneous Generation (1668)
Spontaneous generation: the idea that living organisms generate from nonliving matter, as inferred from rotting meat giving rise to maggots (fly lavae) Animation of Redi’s experiment

5. Cell History
Robert Hooke: examined thin slices of cork, noted appearance of regular box-like structures he names “cells” (1665)
Without realizing it, Hooke discovered the fundamental unit of all living things

6. Cell Theory
1. The cell is the basic unit of structure and function of all living things (Schleiden 1838, Schwann 1839)
Mathias Schleiden identified the first plant cells and concluded that all plants made of cells.
Thomas Schwann made the same conclusion about animal cells.
2. All cells arise from preexisting cells by cell division (Virchow1855)

7. Cell Theory: The History of the Cell
All known living things are made up of cells.
The cell is structural & functional unit of all living things. (at least one cell)
All cells come from pre-existing cells by division, (i.e. Spontaneous generation does not occur).

8. Types of Microscopes Used Today:
Light Microscope:
uses a beam of light to produce image; LIVING tissue/organisms
Compound Light microscope: multiple lenses (scanning, low, high power)
Electron Microscope:
uses an electron beam to produce image; more powerful than light; for NON-LIVING things
Scanning (SEM): external surface of cells
Transmission (TEM): internal structures of cells

9. Electron microscopes

10. Microscope Images Light microscope Scanning e- microscope
Transmission e- microscope
Scanning e- microscope

11. Everyday things under a scanning electron microscope

12. Goal: Students will be able to compare and contrast the structures of prokaryotes and eukaryotes; plant and animal cells.
Plant
Animal
Eukaryotes
(Protists,
Animal, Plant,
Fungi)
Prokaryotes
(Archaebacteria,
Eubacteria)

13. Visualizing Cells- Scaling and Size

14. What makes a cell distinct from its surroundings?
The thin membrane which surrounds all cells is essential in controlling exchange between the cell and its environment
Partially Permeable
Effective barrier
Allows for control
Freely Permeable
Chemicals of cell would mix with surroundings
No life

15. Visualizing Animal and Plant Cells
The material between the nucleus and cell surface membrane is the cytoplasm. (aqueous: fluid to jelly)
Organelles are functionally and structurally distinct parts of a cell.
Compartmentalization →division of labor (sharing of work between specialized organelles)

16. Prokaryotes Lacks internal compartments. No true nucleus.
Most are single-celled (unicellular) organisms.
Have circular DNA and ribosomes
Have cell wall
Some extra layer (PEPTIDOGLYCAN)
Examples: bacteria

17. A general prokaryotic cell

19. Microscopic Prokaryotes
MRSA Staph. bacteria
E. Coli bacteria

20. Eukaryotes Includes plant, animal, fungi and protists
Have several internal structures (organelles).
True nucleus: DNA is encapsulated
Either unicellular OR multicellular.
unicellular example: yeast
multicellular examples: most plants and animals

21. Visualizing Animal and Plant Cells using Light Microscopes
Cell surface membrane (aka plasma membrane)
Nucleus- large; stains very darkly (especially chromatin)
Nucleolus- located within the nucleus stains; even more deeply colored (variable amount; can be ~1-5); where ribosomes are made

22. Eukaryotic Cell

24. Microscopic EUKARYOTES
Paramecium (Protist)
Amoeba (Protist)
NOT PROKARYOTES!!! (i.e. Bacteria)
Yeast (Fungi)

26. Structures Visible with LIGHT Microscopes
Plasma (cell) membrane
Nucleus
Mitochondria (single mitochondrion) - The most numerous organelles seen with light
Golgi apparatus- only be seen with silver containing stains
Lysosomes
Rough ER

27. Animal Cells Only!
Centriole- appears as a small structure close to the nucleus; involved in nuclear division- MITOSIS!

28. Plant Cells Only Usually larger than animal cells
All surrounded by cell wall
Linked to neighboring cells by plasmodesmata (single plasmodesma)

29. Plasmodesmata (plants only)

30. Plant Cells Only Large central vacuole, surrounded by tonoplast
Chloroplasts: show grana (single granum) at high magnification

31. I=observed size of the image
Light Microscopes
There is a limit to how much can be seen w/light
Magnification is the number of times larger an image is, compared with the real size of the object.
𝒎𝒂𝒈𝒏𝒊𝒇𝒊𝒄𝒂𝒕𝒊𝒐𝒏= 𝒐𝒃𝒔𝒆𝒓𝒗𝒆𝒅 𝒔𝒊𝒛𝒆 𝒐𝒇 𝒕𝒉𝒆 𝒊𝒎𝒂𝒈𝒆 𝒂𝒄𝒕𝒖𝒂𝒍 𝒔𝒊𝒛𝒆 Or
𝑴= 𝑰 𝑨
I=observed size of the image
A= actual size

32. Magnification I
NEED TO KNOW! M × A

33. Check Your Understanding
This length of the displayed lymphocyte is 36 mm. The actual length of the lymphocyte is 6 µm. What is the magnification? (Pg 9, Ex2)

34. Check Your Understanding
(Pg 9, Ex2)
This length of the displayed lymphocyte is 36mm. The actual length of the lymphocyte is 6µm. What is the magnification?
1.) Convert mm → µm
36𝑚𝑚=36×1000𝜇𝑚=36,000𝜇𝑚
2.) Use the equation 𝑀= 𝐼 𝐴 to calculate magnification
(M=magnification, I= image size, A=actual size)
𝑀= 36,000𝜇𝑚 6𝜇𝑚
𝑀=×6,000

35. Let’s Practice! FINISH FOR HOMEWORK! Worksheet
Activity 1 – Pollen Grain
Activity 2 – Human leukocyte and pollen grain from oriental lily
FINISH FOR HOMEWORK!