Cell Structure and Function Notes Discovery of the Cell :

1. Cell Structure and Function Notes Discovery of the Cell: • Mid 1600’s scientists began using microscopes to observe living things • Robert Hooke used microscope to observe thin slice of cork—dead plant material • Cork seemed to be made of box-like chambers—Hooke called cells • Anton van Leeuwenhoek discovered • living cells in pond water

2. Cell Theory: • All living things composed of cells • Cells are the basic unit of structure and function in living things • New cells are produced from existing cells

3. Cell and its Environment: • Organisms made of one cell—unicellular organisms Ex: bacteria • Organisms made of many cells—multicellular organisms Ex: plants, animals

4. Each cell must be in “balance” with its environment, exchange food, waste, H2O, CO2, O2 etc. • Process by which organisms maintain a relatively stable internal environment—homeostasis

5. Cell: • Organisms that do not have a distinct nucleus—prokaryotic(PRO = NO) • Ex: bacteria • Organisms with cells that have true nucleus and organelles—eukaryotic (EU = TRUE) • Ex: plants, animals, fungi

6. Cell Parts and Their Functions: Specialized cell parts called organelles— “little organs”

7. Cell membrane—determines what goes in and out of the cell

8. 2. Cytoplasm—gel-like medium that holds the organelles in position

9. 3. Nucleus—control center of the cell • Double membranethat surrounds the nucleus—nuclear membrane • Hereditary information inside the nucleus—chromatin (DNA)

10. 4. Ribosomes—makes proteins

11. 5. Rough Endoplasmic Reticulum (roughER)— makes and transports proteins within the cell • Called rough ER because of the ribosomes found on its surface

12. Smooth Endoplasmic Reticulum (smooth ER)—makes and transport lipids and other materials within the cell • Called smooth ER because no ribosomes found on its surface

13. Cytoskeleton—network of protein • filaments that helps cell maintain its shape

14. Golgi apparatus—processes and • packages proteins and other substances produced in the ER

15. Mitochondria—energy source of the cell • (powerhouse)

16. Vacuoles—sac-like structures for storage • Plant cells usually contain a large vacuole that fills most of the cell—pressure from this large vacuole helps plants support themselves

17. Found in animal cells only: • Lysosomes—cleans up the cell and • digests unwanted materials

18. Found in plant cells only: • Cell wall—provides support and • protection for cell • Composed mainly of cellulose (plant starch)—fiber for our diet • Chloroplast—makes glucose using the energy • from the sun (photosynthesis)

19. Specialized Parts for movement: • 1. Cilia (like little hairs) 2. Flagella (like a tail)

20. Specialized Cells: Different cells in your body do different jobs. The structure (how it’s built) of cells matches the function (what it does).

21. Plant Examples: • Leaf cell—contains many chloroplasts to maximize photosynthesis • Root cell (potato)—contains many vacuoles to maximize water and starch storage

22. Animal Examples: • Epithelial cells—have villi to increase nutrient absorption; found in the intestines chloroplast

23. 2. Muscle cells—contain many mitochondria to produce more energy for movement

24. 3. Nerve cells—have fibers called dendrites that allow nerve cells to communicate with each other

25. Plant cells vs. Animal Cells Plant cell Animal cell Both