The Cell As A “City”

1. The Cell As A “City” Each organelle has a job---your cells run like a little city with many jobs to be done.

2. Lets take each organelle and put it’s job into a “life” situation. . . . • Nucleus—basically like the boss, mayor, principal, chairman of the board—get the picture? • Job—to direct all the cell’s activities, even reproduction.

3. Surrounding the city is the . . . • Cell membrane—this acts like a fence or gate. Why?-it allows some things in and keeps other things out. It can bring things in or take them out and uses energy to do accomplish this-- (active transport).

4. There is more to the nucleus. . . • Remember the nucleus is the “control center” • The nucleus is surrounded by a membrane called the nuclear envelope. This is a protection for the nucleus. Envelopes protect the letter inside—in this case, the nuclear membrane protects the nucleus.

5. The nuclear envelope has “PORES” • Materials pass in and out of the nucleus through the pores in the nuclear envelope.

6. Think of the this movement as a traveling/jumping through the pore to deliver or remove substances.

7. Chromatin is in the nucleus---? • What is it? • Genetic material (DNA) • SO----?!?! • The genetic material contains the instructions for directing the cell’s activities! It also makes you tall, short, brown hair, etc. • This ensures that a leaf cell grows and divides to form more leaf cells or a puppy has puppies and not kittens.

8. Nucleolus • This structure is inside the nucleus and produces ribosomes.

9. Mitochondria • These appear as jelly-bean shaped; their job is to take the food that the organism ingests and convert it into energy. The nickname for the mitochondria is “The Powerhouse”

10. Endoplasmic Reticulum (ER) • The highway of the cell. They appear as mazes of passageways. Proteins and other materials are carried from one area of the cell to the other.

11. Ribosomes • These can be attached to the ER itself or freely floating out in the cytoplasm. Ribosomes are small, grain-like bodies. They are factories that produceproteins for the cell. Most proteins are then sent to the Golgi bodies.

12. Cytoplasm • This is the jelly-like substance that all organelles float in. Cytoplasm actually helps the organelles move (stream) around in the cell. • Cytoplasm is basically clear. • This slide has been stained-------

13. Golgi Body • This is like the packing/shipping department. • Proteins are sent here and packaged up to be sent out to other parts of the cell. Materials can also be sent outside the cell.

14. Vacuoles • These are storage areas in the cell. They may contain food, water and also waste. The vacuole is large in a plant cell; small or even absent in an animal cell.

15. Lysosomes • Small, round structures which contain chemicals to break down certain materials—you can think of lysosomes as a clean-up crew. The contents are enzymes, acids, etc.

16. Chloroplasts—only in Plants!!! • Otherwise we would be. . . . . . . • Green People!

17. Seriously—a chloroplast is for. . . • Photosynthesis—In this process, plants make the food for the themselves by using CO2, water and sunlight.

18. What else does a plant have that an animal cell does not? • Cell Wall • Cell walls provide • structure and • protection for the • cell.

19. So------- • Plant lots of trees so we have lots of fresh oxygen!!!

20. Mitochondria –vs- chloroplast • They do not really look the same!!!

21. WOW—do you have all that now? • Remember—think of the cell as a mini-city where each organelle has a job to do— • Nucleus-boss/control center-remember the nucleolus and the nuclear membrane are with the nucleus. • Cytoplasm-something soft to sit in-jelly-like substance • Ribosome-produces proteins • Lysosome-cleanup crew/janitor (contains enzymes) • Endoplasmic reticulum-highway to move to different areas of the cell. • Golgi body—packing/shipping department • Vacuole-storage area • Mitochondria-produces power (powerhouse) for energy needs • Cell membrane-like a gate to let things in and out-also separates the inside of the cell from the environment outside.

22. What parts are missing? • Plants only—cell wall and chloroplasts!

23. What color would we be if we could perform photosynthesis? • Green--- of course!—like Hulk

24. Well—do your brains hurt? • I sure hope so!!! • You earned it!

25. Test is soon--- • Remember proper science names and all the functions of each organelle plant and animal-there are only 11 total.

26. Good luck and. . . • Study hard!! • The end