1. How Can Organisms Maintain Life?
Prokaryote (Plant and Animal Cells)
Eukaryote (bacteria)
Multicellular

2. Looking Inside Cells (basic unit)
Cells contain Tiny structures called organelles, which carry out specific functions to keep the cell alive

3. Cell Wall Surrounds the cells of plants and some other organisms
Rigid layer of nonliving material (cellulose)
Protects and supports

4. Cell Membrane Controls what substances come into or out of the cell
Thin selectively permeable coating
Surrounds cell (just inside cell wall or on the outside of cells without a wall)

5. Nucleus Cell’s control center Directs all of the cells activities
Nuclear membrane surrounds and protects
Pores in membrane allow materials to pass through
Chromatin contain genetic material, the instructions that direct the functions of cell
Nucleolus produces ribososmes

6. Mitochondria
Produces most of the energy needed by the cell (ATP) through chemical reactions
The“Powerhouse” of the cell
Contains its own DNA (mother’s)
Surrounded by two membranes-
inner has long folds to increase
surface area

7. Microscope View of the Mitochondria

8. Endoplasmic Reticulum
Carry proteins and other materials from one part of the cell to another
Maze of passageways

9. Two Types of ER -Not covered with ribosomes
-Involved in the synthesis of steroids, regulation of calcium levels, and breakdown of toxins
Covered by ribosomes
Make proteins to be exported or inserted into the cell membrane

10. Microscopic Views of Endoplasmic Reticulum

11. Ribosomes Function as factories to produce proteins
Attached to surface of endoplasmic reticulum or floating in the cytoplasm

12. Golgi Bodies Cell’s mailroom
Receive protein and other newly made materials, package them and distribute them to other parts of the cell
Look like a collection of sacks and tubes

13. Microscopic View of the Golgi Apparatus

14. Chloroplasts
Only found in the cells of plants and some other organisms
Capture energy from the sun and use it to produce food for the cell (photosynthesis)
Gives plants their green color

15. Vacuoles Storage area of the cell
Most plant cells have one large vacuole
Store water, food, and other needed materials
Store waste until disposed of

16. Lysosome More common in animal cells than plant Cell’s cleanup crew
Contain chemicals that beak down large food molecules or old worn-out cell parts

17. Lysosome Destroying a Mitochondrial Membrane

18. Cytoskeleton -Maintains shape and size -Long protein strands
-Helps in the movement of organelles in the cell

19. Microfilaments Smallest strands that make up the cytoskeleton
Microtubules - largest strands of the cytoskeleton, during cell division extend across the cell (spindle fibers) and assist in the movement of chromosome

20. Cilia and Flagella -Hairlike and extend form the surface of the cell
-Assist in movement
-Cilia: short and many present in number
-Propel organisms through fluid

21. Bacterial Cells Usually smaller than plant or animal cells
Called Prokaryotic cells
Have cell walls and cell membranes and ribosome
Genetic material not enclosed in a nucleus
Does not contain the other organelles

22. Specialized Cells Multicellular organisms contain specialized cells
These may be different in size and structure because of the different functions
Examples include nerve cells, blood cells, skin cells, etc.

23. How do cells specialize or differentiate?
All of the cells in a multicellular organism have the same DNA.
The cells differentiate by only reading part of the genetic code. The part of the code needed to do a specific job.
For example bone cells use only the part of the DNA code that is for making bone. Even though the entire set of directions is present only the part for bone is used.

25. Levels of organization in multicellular organisms
Specialized cells working together to perform a job for the organism are called tissue.
Different tissues that work together to perform a job are called organs
Different organs that work together to perform a job are called organ systems
The organ systems working together form the organism.