1. 1.1 Studying the Structure of Cells

2. The Cell Theory  The 3 main ideas are  All living things are made of one or more cells  The cell is the basic organizational unit of life.  All cells come from pre-existing cells.

3. All living things are made of cells. Our bodies are made up of between 10 trillion (10 13 ) and 100 trillion (10 14 ) cells. A cell is the basic unit of life. Each contains smaller parts called organelles. These organelles have special functions that maintain all the life processes of the cell. What is a Cell?

4. nucleus nucleolus smooth endoplasmic reticulum ribosomes (small brown dots) Golgi apparatus mitochondrion cell membrane cell wall central vacuole cytoskeleton wall of adjacent cell chloroplast cytoplasm chromatin Plant Cell rough endoplasmic reticulum

5. Animal Cell

6. Cell Wall  in plant cells, not animal  A tough, rigid structure lying just outside a plant cell’s membrane  Provides support for the plant cell and protection for the cell organelles

7. Cell Membrane  Separates the inside of the cell from the external environment  Controls the flow of materials into and out of the cell

8. Nucleus  Brain of the cell  Controls all cell activities  Contains nearly all the cell’s DNA and with it, the coded instructions for making PROTEINS and other important molecules

9. Nuclear membrane  Surrounds nucleus  Protects the contents of the nucleus  Dotted with thousands of nuclear pores, that allow materials (such as ribosomes) in and out

10. Inside the nucleus we see…  a granular material called…  CHROMATIN  Chromatin= DNA + protein  Usually spread out in nucleus  During cell division, chromatin clumps together or condenses…we call this….  CHROMOSOMES

11. Chromosomes  Threadlike structures that contain genetic information that is passed on from one generation to the next

12. Nucleolus  Small dense region inside the nucleus  Function: makes ribosomes

13. Cytoplasm  jelly-like substance that fills the cell  includes the cytosol (fluid), the organelles, and other life-supporting materials, such as sugar and water 13

14. Endoplasmic reticulum (ER)  Connected to the nucleus  Network of membrane-covered channels that transport materials made in the cell  2 types  Rough ER (has ribosomes on it)  Smooth ER (no ribosomes)

15. Ribosomes  Helps to make proteins  Proteins make up much of a cell’s structure and are required for activities necessary for the cell’s survival  Scattered throughout the cell  Some float in the cytoplasm, and others are attached to the ER are attached to the ER

16. Golgi Body (Apparatus)  Function: modifies, sorts, and packages proteins and other materials from the ER for transport out of the cell

17. Vesicles  Membrane- covered sacs that transport materials inside the cell and help these materials cross the cell membrane to enter or exit the cell

18. Vacuoles  Sac-like organelles  Function: stores material such as water, salts, proteins, and carbohydrates  Plant cells have a single, large central vacuole, whereas animals may have several smaller vacuoles

19. What is the one thing all living things need to eat, breathe, reproduce, move and much more? ENERGY!!!!

20. Two ways cells get energy…  from food molecules  from the (plants)

21. Mitochondria (singular: mitochondrion)  Convert chemical energy stored in glucose into compounds that are more convenient for the cell to use  Has 2 membranes  Inner membrane  Outer membrane

22. Chloroplasts  trap energy from the sun to make glucose  PHOTOSYNTHESIS  2 membranes

24. Cytoskeleton  Helps the cell maintain its structure and provides “tracks” along which vesicles and organelles can move  2 main parts  Microtubules  Microfilaments 24