1. Cells
Biology

2. How many cells do we have?
There are approximately 1x1014 cells in the human body…
1,000,000,000,000,000
Oh, that’s about 100 trillion!

3. Cell Theory
All living things are composed of one or more cells.
The cell is the smallest entity that retains the properties of life.
New cells arise only from cells that already exist.

4. Organelles
Organelles = specialized subunit within a cell that has a specific function, and is usually separately enclosed
Like organs in our bodies, cells have organelles.

5. Animal Cell Cytoplasm Ribosomes Cell Membrane Vacuole Nucleus
Mitochondria
Smooth Endoplasmic Reticulum
Rough Endoplasmic Reticulum
Vacuole
Golgi Complex

6. Cell Membrane/ Plasma Membrane
Nickname: “The gatekeeper”
Function:
separates the inside of the cell from the external environment
controls the flow material into and out of the cell

7. Cell Membrane/ Plasma Membrane
The cell membrane allows only some substances to pass through it.
Therefore, it is called a “semi-permeable” membrane.

8. Cytoplasm
a thick liquid residing between the cell membrane holding all organelles

9. Cytoskeleton Nickname: “The Skeleton” Function:
cellular "scaffolding" or "skeleton" contained within the cytoplasm and is made out of protein
Gives the cell structure and shape
Act as rail road tracks for moving things around

10. Cytoskeleton
Microtubules
Actin Filaments

11. Nucleus Nickname: “The Control Center” or “Brain” Function:
Controls all cell activities
Holds the DNA (genetic material)
Regulates gene expression

12. Mitochondria Nickname: “The Power House” Function:
Produces energy to power cell activities

13. Ribosomes
Nickname: “Protein Factory”
Function:
Make proteins

14. Endoplasmic Reticulum (ER)
Nickname: “Roads”
Function:
Internal delivery system of the cell
Made up of channels that transport material made in the cell from one place to another

15. 2 Types of Endoplasmic Reticulum
Smooth Endoplasmic Reticulum (SER)
No ribosomes attached
Makes fats or lipids
Rough Endoplasmic Reticulum (RER)
Has ribosomes attached
Helps make proteins
Products of the ER become enclosed in vesicles and travel to the golgi apparatus

17. Golgi Apparatus Nickname: “The Shippers” Function:
Sorts products from the ER and packages them into vesicles
packages, modifies, and transports materials to different location inside/outside of the cell

19. Vesicles Nickname: “Delivery Person” Function:
small membranous spheres that transport materials around cell

21. Lysosomes Nickname: “Clean Up Crew” Function:
Contain proteins (enzymes) that break down food into smaller particles that the rest of the cell can use
Destroy old cells, recycle the parts
Destroy invaders

22. Lysosomes
Fuses with other vesicles to digest nutrients brought into the cell or destroy dangerous microorganisms.

24. Centrioles Nickname: “Spiderman” Function:
Protein tubes that play a role in cell division
Shoot out spindle fibers that guide chromosomes during cell division

25. Plant Cells Central Vacuole Chloroplasts Cell Membrane Cell Wall
Section 7-2
Central Vacuole
Chloroplasts
Cell Membrane
Cell Wall
Go to Section:

26. Plant Cells Cytoplasm Central Vacuole Smooth ER Ribosomes Chloroplasts
Cell Membrane
Cell Wall
Nucleolus
Golgi Bodies
Nucleus
Mitochondria
Rough ER

27. Cell Wall
Function:
provides support and protection to the cell membrane
Location:
Outside the cell membrane in plant cells

28. Chloroplast (a type of Plastid)
Nickname: “Powerhouse of Plants”
Function:
Traps energy from the sun to produce food for the plant cells (photosynthesis)
Contains chlorophyll = the green pigment that begins the process of photosynthesis

30. Chloroplast

31. Chloroplasts Under a Microscope

32. Central Vacuole Function: Store water
Vacuoles play a role in turgor pressure
When a plant is well-watered, water collects in cell vacuoles producing rigidity in the plant
Without sufficient water, pressure in the vacuole is reduced and the plant wilts

33. Comparing Plant and Animal Cells
Plasma membrane
Nucleus
Mitochondria
Ribosomes
Golgi
Endoplasmic Reticulum
Cytoplasm
Cytoskeleton
Small vacuoles
Centrioles
Lysosomes
Cell wall
Plastids
Chloroplasts
Central Vacuole