Ch. 7 Notes

1. Biology of Cells Ch. 7 Notes

2. History of Cells • Robert Hooke (1665). • Observed “cork.” Said “cork was made of little compartments that looked like monk’s “cells.”

3. Modern Cell Theory • Cell Theory: • ***Cells are the smallest working units of life. • ***All living things are made of cells. • ***All cells come from pre-existing cells.

4. Cell Factory • The cell is like a factory. • People and machines perform functions in a factory. • There are parts of a cell that also perform different functions.

5. Cell Factory • All factories produce a product. CELL PRODUCT=PROTEINS • Cell’s DNA codes for proteins! • All cells in an organism have the same DNA, but different cell types produce different proteins. • What is needed to build a protein?

6. Parts of All Cells • Cytoplasm- watery substance inside all cells. • Consists of water and anything in it.

7. Parts of All Cells • ALL CELLS HAVE A CELL MEMBRANE • Cell membrane- “door” to the factory that’s made of lipids and proteins. • Also known as the phospholipid bilayer. • Semi-permeable-only certain things pass through. • Aids in homeostasis—stable internal conditions

8. Phospholipid Structure

9. Phospholipid Structure • Hydrophilic = “water loving” • Hydrophobic = “water hating”

10. Cell Membrane Structure

11. Parts of All Cells • Receptor proteins- allow cells to talk to one another. • Cells send “messages” and others receive them with receptors. • Hormones-cellular messages Ex.) Testosterone

12. Parts of All Cells • Marker proteins -gives your cells an “identity.” • Distinguishes your cells from other cells. • Blood and tissue types • Immune system A marker B marker A and B markers No marker

13. Parts of All Cells • Channel proteins -allow molecules to pass through the membrane. • Selective about what passes through.

14. Ribosomes -“assembly line workers.” They build proteins. Found all over cell Once built, proteins are either used by cell or shipped out to other cells. Parts of All Cells

15. Bacteria Small No organelles except ribosomes. No nucleus. Simple Anything other than bacteria, like plants and animals, have these cells Large cells. Organelles. True nucleus. Complex Prokaryotic vs. Eukaryotic Cells

16. Eukaryotic Cells Organelles - little, specialized organs found in all eukaryotic cells, not prokaryotic.

17. Nucleus-“central office” of the cell that contains DNA where most cell activity is started DNA carries instructions for how to build something. What? Nucleus is surrounded by a porous membrane. Why? Another organelle the nucleolus, is found in the nucleus and makes the ribosomes. Cell Video —4min Eukaryotic Organelles

18. Eukaryotic Organelles • Mitochondria-powerhouse of the cell where cellular respiration occurs. • Some cells have more than others—why? • Contain own DNA • Supplies cell with energy through cellular respiration--convert food energy (carbs) to cellular energy (ATP).

19. Eukaryotic Organelles • Cellular respiration- process that occurs in mitochondria in which organisms consume carbohydrates and oxygen, releasing carbon dioxide, water, and energy for life (ATP). • C6H12O6 + 6O2 → 6CO2 + 6H2O + energy (ATP) • This is why we use oxygen and how we use carbs to get energy!!! • Plants and animals all respire • The opposite of photosynthesis!!!

20. Eukaryotic Organelles • Endoplasmic reticulum -“highway” system throughout inside of cell. • Materials can travel on it throughout the cell. • Rough ER vs. Smooth ER.

21. Eukaryotic Organelles • Golgi apparatus-“packaging center” of the cell. • Puts finishing touches on proteins and prepares them for shipment out of the cell.

22. Eukaryotic Organelles • Lysosome -recycling center. • Repairs damaged cell parts. • Sometimes parts are beyond repair.

23. Eukaryotic Organelles • Vacuoles-storerooms in plant and animal cells. What would they store? • Larger in plant cells than animal cells. Why? • If they shrivel, so does the cell

24. Cell wall for structure AND cell membrane. Larger vacuoles. Chloroplasts Cell membrane only. Small vacuoles. No chloroplasts. Plant vs Animal Eukaryotic Cells

25. Plant vs Animal Eukaryotic Cells

26. Plant Eukaryotic Cells • Cell wall -surrounds the plant cell membrane • Is made of cellulose, a carb—paper is this. • Give plant cells support and structure • Protect cell from bursting if vacuole absorbs a lot of water

27. Chloroplast-organelle where photosynthesis occurs. Have DNA like mitochondria Chlorophyll-green pigment in chloroplasts that gathers sunlight needed for this process Plant Eukaryotic Cells

28. Plant Eukaryotic Cells • Chloroplasts found only in photosynthetic organisms (plant cells, some bacteria, and some protists) • Make energy source (carbs) from light

29. Source of energy for ALL life on Earth!!! Reactants Water Carbon Dioxide Sunlight Products Oxygen gas Glucose (a carb) Photosynthesis in Plant Cells

30. Photosynthesis in Plant Cells

31. Photosynthesis in Plant Cells Photosynthesis Cellular Respiration

33. Endosymbiotic Theory • Endosymbiotic Theory -mitochondria and chloroplasts were once prokaryotic cells that were taken in by other prokaryotes. • Creation of first eukaryotic “organelles” • Prokaryotes evolved into eukaryotes • Endosymbiotic Theory—3min