1. cells

2. Little Bit of Science History
Hooke (1665) - used a primitive microscope observing cells for the first time and naming them “cells”
Hooke’s drawing of cork cells
Early compound microscope (2 lenses)

3. More History Van Leeuwenhoek - 1674 first to use a microscope to
look at living cells in pond water
and just about anywhere else even
the plaque on his teeth!
Spirogyra
Vorticella

4. And Yet More History Schleiden and Schwann - 1839 Virchow - 1857
Schleiden stated that all plants are made up of cells.
Schwann stated that all animals are made up of cells.
Virchow
States that “every cell stems
from another cell.”

5. All of that History Gave Rise to the Cell Theory
All living things are made up of cells
All cells come from preexisting cells
Cells are the basic unit of structure and function in living things (take away the order of a cell and the organism will not survive)

6. Types of Cells
Eukaryote
Prokaryote

7. Prokaryotes ‘Before the Nucleus’
Archaebacteria and Eubacteria
No nucleus, but all living things have DNA?
Smallest type of cell ( microns)
No membrane bound organelles
Unicellular / Simpler

8. Prokaryotes don’t have a nucleus !
DNA loosely organized close
to the cell membrane

9. Prokaryotes don’t have organelles
Organelle - specialized structures within a cell with a specific function, separated by a membrane.
But they do have ribosomes,
protein factories.

10. Eukaryotes True Nucleus
Have a nucleus where DNA is protected away from the rest of the cell
Have membrane-bound organelles
Larger / more complex
Found in plants, animals, fungi and protists
Most multicellular but some uni- and others are colonial

11. Modern History The Endosymbiotic Theory Lynn Margulis
Explanation as to how
eukaryotic cells evolved.
Margulis' original hypothesis proposed that aerobic bacteria (that require oxygen) were ingested by anaerobic bacteria (poisoned by oxygen), and may each have had a survival advantage as long as they continued their partnership.

12. Cell Parts and Functions
Remember this?

13. Cell Membrane All cells have a cell membrane Boundary that allows
selected materials to pass
through
Cell-to-cell recognition
receptors made of
glycoproteins
Gatekeeper/Bouncer
Phospholipid Bilayer

14. Cell Wall Found in plants, fungi, protists and bacteria
Protective support for the organism
Plants made up of CELLULOSE
Porous allows H2O, CO2, and O2 through

15. Directs all cell activities
Nucleus
Directs all cell activities
Contains and protects
the DNA
Includes:
Nuclear Envelope
Nuclear Pores
Nucleolus
Chromosomes/
Chromatin

16. Nuclear Envelope Lipid bilayer that protects the DNA from the
cytoplasm
Nuclear pores allow proteins and RNA
to travel into the cytoplasm but
prevent DNA from leaving
Nuclear envelope is continuous
with the endoplasmic reticulum

17. Nucleolus Made up of protein and RNA Site of ribosome synthesis
Nucleus
Made up of protein and RNA
Site of ribosome synthesis

18. Cytoplasm (Cytosol) Jelly-like material that surrounds
and encases the organelles
Many chemical reactions occur
in the cytoplasm
Mostly made-up of water
and enzymes

19. Plastids (plants only)
Chloroplast
Leucoplast
Chromoplast
Photosynthetic factory of the cell
Storage of starch
(polysaccharide)
Contain pigments
such as carotenoids
Production of glucose using the energy of sunlight
Cells of the potato are
filled with leucoplasts
Gives tomatoes their color

20. Ribosomes
Mammalian cell can synthesize 20,000 ribosome subunits per minute
Tiny protein factories, made in the nucleolus then moved into the cytoplasm or attached to the endoplasmic reticulum
Made up of 2 subunits

21. Endoplasmic Reticulum
2 Types: Rough and Smooth
Rough - ribosomes attached
important in protein synthesis,
packages new proteins and sends them to the
Golgi apparatus
Smooth - no ribosomes
contains many enzymes that serve different functions;
liver cells detoxifies drugs and breaks down glycogen,
muscle cells involved in calcium release needed for muscle contraction

22. Mitochondria Powerhouse of the cell Site of cellular respiration
Contain DNA can replicate
independent of the cell
Site of cellular respiration
Convert chemical energy in food
into usable cell energy (ATP)

23. Golgi Apparatus Flattened stack of pancakes Attaches carbohydrates
Modifies, collects, packages
and distributes molecules
Attaches carbohydrates
and lipids to proteins
Flattened stack of pancakes

24. Lysosomes Primarily found in animal cells Small bubble-like
Filled with enzymes necessary for digestion of unneeded cell parts
Recycling center of the cell

25. Vacuoles / Vesicles Vesicles are small storage structures
that can fuse with membranes to release materials
Vacuole is very large, stores water and sugars for the plant

26. Cytoskeleton 2 Types: Microtubules Microfilaments
Microtubules - hollow tubes, support,
movement of organelles
Framework made of proteins
Microfilaments - long, thin fibers, support and movement of cytoplasm

27. Desmosomes Cell snaps - connect cells together
and create cell junctions for materials
to pass through

28. Centrosomes / Centrioles
Centrosomes - area of the cell close to the nucleus where the centrioles are found
Centrioles only found in animal cells,
used to separate the chromosomes during cell division

29. Chromosomes DNA Tightly coiled chromatin
(DNA when the cell is at rest)
DNA takes the shape of a chromosome
only during cell division