1. They make up everything!
Cells
They make up everything!

2. First things first! There’s ALWAYS a theory! Cell theory states that:
All living things are composed of cells
Cells are the smallest functional part of a living organism
All cells come from other cells

3. Types of Cells
Two Main Types of Cells:
Eukaryotic
Prokaryotic

4. Types of Cells You may also see cells differentiated by: Plant Cells
Animal Cells

5. Prokaryotes Unicellular organisms Found in all environments
No nuclear membrane (aka no nucleus)
Instead they have a nucleoid region
No membrane bound organelles
Simple internal structure
Most primitive (appeared about 4 billion years ago)

6. Prokaryotes Cont’d Includes eubacteria and archaebacteria
Evolved before eukaryotic cells
Structure:
Plasmid (circular) DNA
Ribosomes
Cell membrane
Cell wall (different composition than plants)
Some have capsules outside wall (enhances ability to cause disease  protects from engulfment)
Some have pili or flagella (for movement)

8. Eukaryotes More advanced than prokaryotes
ALL multicellular organisms are eukaryotic
There are some unicellular organisms that are eukaryotic
Complex internal structure
Appeared around 1 billion years ago
YOU are made up by YOUkayrotes!

9. Eukaryotes Cont’d Have nucleus and nuclear membrane
Have membrane bound organelles
Cell membrane
Cytoplasm – everything between plasma membrane and nucleus

10. Unicellular vs. Multicellular
Some Eukaryotic organisms are unicellular = made up of one cell.
We are made up of multiple cells which work together to allow us to function.
Cells  Tissues  Organs  Organ Systems = ORGANISM
We are made up of ~37.2 trillion cells.
How big is that number?
37.2 trillion minutes = 70,729,300 years!!!

11. Animal Cells No cell wall Small of no vacuole No chloroplasts
May have flagella
Have membrane bound organelles

12. Plant Cells Cell wall Large Vacuole Chloroplasts
Flagella in gametes (sex cells) only
Have membrane bound organelles

14. Cell Organelles
Specialized structures that perform important cellular functions in eukaryotic cells
Helps a cell do it’s job!
Can be compared to organs! (see the name resemblance?)

15. Examples of Cell Jobs Making proteins  keratin which is in your hair
Sending signals  nerve cells, how you know how to take your hand off of a hot stove
Turning sunlight to glucose (plants only)
Contracting for movement  muscle cells

16. The Nucleus The BRAIN of the cell
Controls most cell processes by giving specific directions to make proteins
Contains the hereditary information of DNA
Deoxyribonucleic acid
Blueprint of the cell
Copies the genetic material so that when a new cell divides, the new cell is exactly the same as the original cell

17. Cytoskeleton
Network of protein filaments that helps the cell to maintain its shape
Microfilaments  long, thin fibers(smallest)
Microtubules  hollow tubes of protein (thickest)
SUPPORTS the cell
Also involved in cell movement

18. Cytoplasm
Gel-like, viscuous liquid (think mucous) which makes up the majority of the volume of the cell
Made primarily of water but there are also proteins, salts, etc. in it
Forms a lattice that offers internal support for the cell

19. Ribosomes Ribosomes assemble proteins
Located on the endoplasmic reticulum (ER for short)
Also free-floating in the cytoplasm

20. Rough Endoplasmic Reticulum
Rough ER is continuous with the nucleus.
Rough ER is rough because of the presence of ribosomes on its surface.
Ribosomes are responsible for protein synthesis (production) which.
Once the ribosomes produce their proteins, the proteins are stored in sacs called cisternae.

21. Smooth Endoplasmic Reticulum
Is a network of tubes and small sacs called vesicles.
Produces and stores steroids (not just for muscle building but also is a type of molecule that often makes up hormones).
Also serves to store important ions such as calcium which is especially important in muscle contractions.

22. Golgi Apparatus
Takes molecules and puts them into secretory vesicles (small sacs) for transport and eventual export (secretion).
Works closely with the rough ER as it receives vesicles with proteins from the rough ER and re-packages them for export out of the cell.
Also can create simple sugars for export.
Finally, the golgi apparatus produces lysosomes.

23. Lysosomes
Sac (or membrane bubble) filled with enzymes that break down old organelles and large molecules
Kind of like a stomach

24. Types of Lysosome Processes
Phagocytosis – digestion of food particle
Autophagy – breakdown of organelles
Autolysis – self-destruction of whole cell

25. Vacuoles
Sacs that store water and other materials
FOUND IN PLANTS

26. Chloroplasts
Capture the sun’s energy to make glucose in plants and algae
Energy is stored in chemical bonds
Contain their own DNA
FOUND IN PLANTS

27. Mitochondria Powerhouse of the cell
Break the bonds of glucose to release the sun’s energy so it can be stored and used as ATP
Contain own DNA

28. Endosymbiotic Theory
It is believed that mitochondria (and chloroplasts) were once independent prokaryotic cells that were engulfed by larger eukaryotic cells.
Evidence = mitochondria have their own circular DNA which is not replicated by the nucleus, they have their own ribosomes, replicate on their own in a method similar to how prokaryotic cells divide

29. Cell Membrane Regulates what enters and leaves the cell
Lipid bilayer has proteins and carbohydrates embedded in it
Think of it as a guard!
Made up of phospholipids which have hydrophilic heads and hydrophobic tails (does this ring a bell?)

30. Cell Wall
In plants, fungi, and bacteria: it gives support and strength
Plants  made of celllulose
Fungi  made of chitin

31. Word of the Day: COOPERATION
All of the organelles work together to enable the cell to accomplish its job

32. But How Does It All Fit?
There is approximately 6 feet worth of DNA in each one of your cells.
Your cells are SMALL! Your nucleus is EVEN SMALLER.
So how is it that all that DNA can fit?

33. How does it fit? DNA is packaged into chromosomes.
Chromosomes are long strands of DNA that contain many genes.
In humans, chromosomes occur in pairs b/c you inherit one from each parent.
Chromosomes are usually difficult to see BUT when they condense, they can be seen under a light microscope.