The document provides an overview of cell biology, including the history and development of cell theory. It discusses key discoveries such as Hooke observing cells in 1665 and van Leuwenhoek observing single-celled organisms in 1673. The three main components of cell theory developed between 1838-1858 - that all organisms are made of cells, cells are the basic unit of life, and cells come from preexisting cells. The document also describes characteristics of prokaryotic and eukaryotic cells, examples of major cell structures like the nucleus and mitochondria, and differences between plant and animal cells.

1. Cell Biology
Zoljargal Chinbat
Plant biology

2. 
Cell biology is the study of cell structure and function,
and it revolves around the concept that the cell is the
fundamental unit of life.

3. Discovery of Cells
 1665- English Scientist, Robert Hooke, discovered cells
while looking at a thin slice of cork.
 He described the cells as tiny boxes or a honeycomb.
 He thought that cells only existed in plants and fungi.

4. Anton van Leuwenhoek
 1673- Used a handmade microscope to observe pond scum
& discovered single-celled organisms
 He called them “animalcules”
 He also observed blood cells from fish, birds, frogs, dogs,
and humans
 Therefore, it was known that cells are found in animals as
well as plants

5. Development of Cell Theory
 1838- German Botanist, Matthias Schleiden,
concluded that all plant parts are made of cells.
 1839- German physiologist, Theodor Schwann,
who was a close friend of Schleiden, stated that all
animal tissues are composed of cells.

6. Development of Cell Theory
 1858- Rudolf Virchow, German physician, after
extensive study of cellular pathology,
concluded that cells must arise from preexisting
cells.

7. The Cell Theory Complete
The 3 Basic Components of the Cell Theory were
now complete:
 1. All organisms are composed of one or more
cells. (Schleiden & Schwann)(1838-39)
 2. The cell is the basic unit of life in all living things.
(Schleiden & Schwann)(1838-39)
 3. All cells are produced by the division of
preexisting cells. (Virchow)(1858)

8. Modern Cell Theory
Modern Cell Theory contains 4 statements, in addition to
the original Cell Theory:
 The cell contains hereditary information(DNA) which is
passed on from cell to cell during cell division.
 All cells are basically the same in chemical composition and
metabolic activities.
 All basic chemical & physiological functions are carried out
inside the cells.(movement, digestion,etc)
 Cell activity depends on the activities of sub-cellular
structures within the cell(organelles, nucleus, plasma
membrane)

9. Characteristics of all cells
 Surrounded by cell membrane (plasma)
 Contain DNA – genetic material.
 Contain cytoplasm

10. Examples of Cells
Amoeba Proteus
Plant Stem
Red Blood Cell
Nerve Cell
Bacteria

11. Prokaryotic
 No nucleus (nucleoid
region).
 Few internal
structures - have
simple ribosomes.
 Smaller & simpler
than eukaryotic cells.
 One-celled
organisms
 Ex. Bacteria

12. Prokaryotic Cells
 Some use flagellum for locomotion
 threadlike structures protruding from cell
surface Bacterial cell wall
Flagellin
Rotary
motor
Sheath

13. Eukaryotic
 Have a membrane bound nucleus,
control center that holds DNA (genetic
material)
 Contain organelles surrounded by
membranes (small organs)
 Most living organisms – lots of variety
 Larger & more complex than prokaryotic
cells

14. Eukaryotic cells

15. Diversity of Life
 Unicellular
Organisms
 1 cell
 Ex. Bacteria,
Amoeba
 Multicellular
Organisms
 2 or more cells
 Ex. Plants & Animals
 Levels of
Organization
 Cells
 Tissues
 Organs
 Organ Systems

16. Plant Cells vs. Animal Cells
 Plant Cells
 Chloroplasts
 Large Central
Vacuole
 Cell Wall
 Animal Cells
 Lysosome
 Centrioles

17. Organelles

18. Cell Membrane / Plasma
 Outer membrane of cell that
controls movement in & out
of the cell
 Double layer (Lipid Bilayer)
 Plasma Membrane
 Selectively permeable
boundary between the cell
and the environment
 All cells have this!!

19. Cell Membrane / Plasma

20. Nucleus
 Directs cell activities
 Separated from
cytoplasm by nuclear
membrane
 Contains genetic
material - DNA
 Nuclear Membrane
 Surrounds nucleus
 Made of two layers
 Openings allow material to
enter and leave nucleus

21. Chromosomes/Chromatin
 In nucleus
 Made of DNA &
protein
 Contain instructions
for traits &
characteristics
 Contains instructions
for making proteins

22. Nucleolus
 Inside nucleus
 Makes ribosomes
which then leave
the nucleus

23. Ribosomes
 Each cell contains
thousands
 Make proteins (site
for protein
synthesis)
 Found on Rough
ER & floating
throughout the cell

24. Endoplasmic Reticulum
 A system of tubes & sacs
formed by membranes (an
enclosed space)
 Moves materials around
inside of the cell
 Smooth: lacks ribosomes
 Lipid synthesis, drug
detoxifcation
 Rough type (pictured):
ribosomes embedded in
surface
 Transports proteins to the
Golgi body

25. Golgi Bodies
 Protein “packaging
plant”
 Modifies protein
 Attach lipids &
carbohydrates to
the protein

26. Vesicles move from ER to Golgi

27. Mitochondria
 Produces energy
through chemical
reactions – cellular
respiration
 Converts glucose
into ATP
 Cristae – inner
membrane
 Matrix – inner
membrane space

28. What is ATP?
 Nucleotides
 “Carry” chemical energy
from easily hydrolyzed
phosphoanhydride bonds
• Combine to form coenzymes (coenzyme A (CoA)
• Used as signaling molecules (cyclic AMP)

29. Lysosome
 Digestive sac for
proteins, fats, &
carbohydrates
 Transports undigested
material to cell
membrane for
removal
 Cell breaks down if
lysosome explodes(A)

30. Cytoskeleton
 Network of protein fibers supporting cell shape and
anchoring organelles
 Microfilaments
 Actin
 Cell movement
 Support of cell
 Microtubules
 Hollow tubes
 Movement of organelles
 Forms cilia, flagella, centrioles
Cell membrane
Endoplasmic
reticulum
Microtubule
Microfilament
Ribosomes Michondrion

31. Cytoskeleton
Actin
Microtubules
Intermediate
filaments

32. Centrioles
 Assemble
microtubules during
cell division
 Barrel shaped –
pairs
 Found In animal
cells (used during
cell reproduction)

33. Cell Wall
 Most commonly
found in plant cells
& bacteria
 Supports & protects
cells

34. Chloroplast
 Found in plant cells
 Contains green
chlorophyll
 Location where
photosynthesis
takes place in the
cell

35. Vacuoles
 Membrane-bound
sacs for storage,
digestion, and waste
removal
 Contains water
solution
 Help plants maintain
shape- large central
vacuole

36. “Typical” Animal Cell

37. “Typical” Plant Cell