Exploring Cellular Biology: From Microscopes to Mitochondria

1. Chapter 4 Notes BIOLOGY “The Cell”

2. 4-1 CELLS • Science is not static • World is flat • Planets revolve around the Earth • Only things that we can see, exist

3. 1665 • Robert Hooke- England: looked at a thin slice of cork • Where does cork come from? • He saw chambers, and called them “cells” • Why were the chambers empty?

9. 1665… • Anton Von Leewenhoek • Used a single lens microscope to observe pond water • He probably saw paramecium, euglena, and amoebas

11. Metaboly movements of Euglena.

12. Cells are the basic units of life • Cell Theory has 3 parts that are accepted by all scientists….

13. 1. All living things are made up of cells • 1838 Matthias Schleiden – all plants are made of cells • 1839 Theodor Schwann- all animals are made of cells

14. 2. New cells only come from other cells • 1855 Rudolf Virchow said this …

15. 3. Cells are the basic unit of structure and function of all living things. • Atoms are the smallest part that can exist alone • Cells are the smallest part that can exist alone and be considered “alive”

16. Technology: define each on yr own • Fluorescent Labels • Confocal Light microscope • Hi Resolution Video • Electron Microscope • TEM • SEM • Scanning Probe microscope

17. Prokaryotes/ Eukaryotes

18. 4-2 Eukaryotic Cell Structure • Organelles; the mini organs of the cell

19. NUCLEUS • Nucleus- sends out instructions for making proteins “the brain” • Nuclear envelope- separates the nucleus • Chromatin- DNA + protein • Chromosomes- thickened chromatin that are visible during cell division • Nucleolus – dense region of the nucleus where manufacturing of proteins begin

20. CYTOPLASM • Ribosomes- where proteins are assembled • ER- where lipid parts needed for cell membrane are made, also some proteins

21. Rough ER- is invoved in making proteins, ribosomes are found on its surface • Proteins made on these ribosomes, go into the rough er and are modified • Most proteins that are made here will be exported out of the cell • Smooth ER- contains collections of enzymes, ready for action • These enzymes perform specialized tasks like detoxification of drugs • Liver cells contain a lot of smooth ER ? Tylenol, alcohol

22. CYTOPLASM… • Lysosomes: clean up crew • Filled with enzymes, that help digest proteins, lipids, carbs- “get the junk out of the cell”. • Tay Sachs Disease: these don’t function properly

23. Vacuoles • Storage place for water, salts, proteins, carbs • In plants, it is VERY LARGE, and holds water and is under pressure – Making it possible for the plant to support structures like leaves and flowers • Paramecium has a contractile vacuole to pump out excess water

24. CYTOPLASM… • Golgi Apparatus: (discovered by Camillo Golgi) modifies, sorts and packages proteins, from the ER for storage or secretion outside the cell • Customization, finishing touches are put on the proteins- then they are packed and leave the factory

25. Mitochondria- “powerhouse” of the cell, converts chemical energy in food, to a compound the cell can actually use- • Mitochondria has its own simple circular DNA • In humans, Mitochondrial DNA is inherited from your mom • Your heart cells many mitochondria in each cell

26. Chloroplasts w/ chlorophyll • Capture energy from sunlight, and convert it into chemical energy • Contain the pigment chlorophyll

27. Cytoskeleton: protein filaments that help maintain cell’s shape- also involved in movement • Centrioles- help to organize cell division (stars) in animals cells only • Microtubules and filaments: help maintain cell shape- help amoeba move

28. Flagellum/ Cilia- • For movement or sweeping – throat cells • Sperm cells • Cell membrane- both animals and plants p182 • Regulates what enters and leaves • Provides some protection and support

29. Cell wall • Present in plants, algae, fungi, and most prokaryotes • Porous enough to allow water, oxygen and carbon dioxide among other substances through • Fiber- and bowel movement • Strong supporting layer made of cellulose a tough carbohydrate fiber