Discovering Cells: History & Structure Descriptions

1. Standards: • SB1. Students will analyze the nature of the relationships between structures and functions in living cells. • Explain the role of cell organelles for both prokaryotic and eukaryotic cells, including the cell membrane, in maintaining homeostasis and cell reproduction. • SB3. Students will derive the relationship between single-celled and multi-celled organisms and the increasing complexity of systems. • Relate the complexity and organization of organisms to their ability for obtaining, transforming, transporting, releasing, and eliminating the matter and energy used to sustain the organism • DESCRIBE the History of Cell Discoveries • Distinguish between prokaryotic and eukaryotic cells.

2. HISTORY OF CELL DISCOVERIES -1665 – ROBERT HOOKE – First discovered and named cells (in non-living cork) -1673 – Anton Van Leeuwenhoek - “Father of MICROSCOPY”. • *First to describe LIVING CELLS AND MICROSCOPIC STRUCTURES The CELL THEORY: 1800s 1. ALL LIVING THINGS ARE MADE OF CELLS. (Schleiden and Schwann) 2. CELLS ARE THE BASIC UNIT OF LIFE 3. CELLS COME ONLY FROM OTHER CELLS (Virchow)

3. Eukaryotes 1) Have a nucleus and membrane bound organelles 2) Usually multi-cellular 3) Specialized (i.e. heart cell, nerve cell); Differentiate from stem cells (blank cells) 4) Include animals, plants, fungi, and protists Prokaryotes 1) No nucleus or membrane-bound organelles 2) Always unicellular 3) Bacteria are only examples Plant Cells Have a cell wall (cellulose), chloroplasts, and large central vacuole vacuole Animal Cells No cell wall or chloroplasts Many small vacuoles and lysosomes Fungi Cells Have a cell wall (chitin) No Chloroplasts

4. Prokaryotes Nucleoid region contains the DNA • Cell membrane & cell wall • Contain ribosomes (no membrane) to make proteinsin their cytoplasm

5. Contain 3 basic cell structures: Nucleus Cell Membrane Cytoplasm with organelles Eukaryotic Cell

6. Two Main Types of Eukaryotic Cells Animal Cell Plant Cell

7. CELL SIZES

8. Eukaryotic Cells are specialized…Prokaryotic Cells are not…

9. Number of Cells Organisms may be: • Unicellular – composed of one cell • Multicellular- composed of many cells that may organize

10. In Multi-cellular organisms • Cells  • Tissues  • Organs  • Systems  Organism

11. CELLS CAN BE DIVIDED INTO 2 DIFFERENT GROUPS EUKARYOTES -Have organelles and a nucleus -Usually multi-cellular -Cells can be specialized – have a specific function (i.e. nerve cell, muscle cell) -Examples include: ANIMALS, PLANTS, FUNGI and PROTISTS • PROKARYOTES • -Lack ORGANELLES and a NUCLEUS • -Always unicellular • -Cells are not specialized • -The only examples are BACTERIA

12. III. CYTOPLASM_ – Includes • CYTOSOL – Gel inside of cell (mostly water) • ORGANELLES - “mini” organs (see chart below)

21. PLANTS ONLY

22. Journal 4: Begin as You enter: Read pg 74 and MAKE A VENN DIAGRAM TO SHOW THE SIMILARITIES & DIFFERENCES BETWEEN PLANT AND ANIMAL CELLS ANIMAL PLANT DNA RNA

24. CELL QUIZ REVIEW

25. Quiz 3a Review • 1) List the 3 parts of the Cell History • 2) Who named and discovered cells? • 3) Who is the “father of microscopy” who first observed living cells? • 4) Distinguish between prokaryotic and eukaryotic cells. • 5) Distinguish between plant and animal cells. • 6) Describe the proper way to carry a microscope • 7) Describe the proper way to make a slide and observe a specimen under the microscope. • 8) How do you determine magnification (if the ocular lens was 10X and the objective lens was 10X what is the total magnification)? • 9) Name the lab tool used for: • a) Measuring volume (liquid) b) Measuring mass c) Measuring length d) Mixing • 10) Label the parts of the microscope.

28. CELL ANALOGY IN THE SPACE PROVIDED, CREATE YOUR OWN CELL ANALOGY.

29. IV. The Cell Membrane • A. Structure – Composed mainly of TWO organic compounds • 1. Phospholipid bilayer: Forms outer membrane • 2. Proteins: Act as channels and marker to allow materials in and out

31. Remember Lipids ?? • Lipids are made of fatty acids • Lipids (triglycerides) serve as energy storage in animals • Phospholipids don’t store energy, but they form the bilayer of the cell membrane

32. Remember proteins?? • Proteins are made of amino acids • Proteins have a variety of functions – they are the “building blocks” of living things and are catalysts • They include enzymes (end in ase) – remember the lock and key model • In the cell membrane, proteins act as markers and doorways

34. THE CELL & ITS ENVIRONMENT • Cells must move molecules through the cell membrane to maintain HOMEOSTASIS (balance between concentrations inside and outside cell) • CONCENTRATION = amount of solute dissolved in a solvent • In which cell is the salt concentration higher?

35. B. SELECTIVELY-permeable – Controls what enters and leaves • 1. Passive Transport: From high to low concentration; No energy required • a. Simple diffusion: Movement of solutes from high to low concentration • directly through the cell membrane • b. Osmosis: Diffusion of water from high to low concentration

36. 2. OSMOSIS = DIFFUSION OF WATER • i. Hypotonic: A solution with less (“hypo”) solute and more water than the cell; Water will enter the cell causing it to swell • -Animal cells left in a hypotonic solution may burst (hemolysis) • -Plant cells left in a hypotonic solution will have turgor pressure (vacuole presses against cell wall causing it to stand upright • ii. Hypertonic: A solution with more (“hyper”) solute and less water than the cell; Water will leave the cell causing it to shrink • iii. Isotonic: A solution with the same amount of solute and water as the cell; Water will move back and forth at the same rate and the cell will remain at equilibrium (not change size)

37. EXPLAIN WHAT IS HAPPENING

38. Red Blood Cell Animation

39. What happens when you don’t water a plant?

41. EFFECTS OF SOLUTIONS ON CELLS – HOW CELLS MAINTAIN HOMEOSTASIS PURE WATER SALT WATER

42. THINK ABOUT IT • HOW COULD SOMEONE DIE BY CONSUMING TOO MUCH PURE WATER? • IF YOU WERE ON A DESERT ISLAND, WOULD YOU BE BETTER OFF DRINKING THE OCEAN WATER OR DRINKING NOTHING AT ALL? • WHY ARE PEOPLE HOOKED UP TO A .09% SALINE SOLUTION IF THEY NEED FLUIDS?

43. Concept 9 – FOR SOLUTIONS A, B, AND C INDICATE:i) Type of solutionii) What will happen to the cell A B C

44. What happens when you don’t water a plant?

45. c. Facilitated diffusion: Solutes that are too big to fit through the lipid bilayer are helped (“facilitated”) across the cell membrane. It is still passive (high to low).

46. II. Active Transport - Requires Energy (ATP) to move substances up concentration gradient a. Solute pumping: Moving solutes from low to high concentration (uses ATP)

47. b. Endocytosis: Movement of large materials into cell i. Phagocytosis: “Cell Eating” – Cell consumes large particles/cells lysosomes ii. Pinocytosis: “Cell drinking” – Cell consumes small solutes c. Exocytosis: Movement of materials out of cell (usually from Golgi)

48. MOLECULES CAN MOVE INTO OR OUT OF CELLS BY EITHER: I. PASSIVE TRANSPORT – NO ENERGY a. DIFFUSION / OSMOSIS b. Facilitated Diffusion 2. ACTIVE TRANSPORT (REQUIRES ENERGY) HIGH LOW HIGH LOW

49. IV. CELLWALL– Tough, outer layer outside of cell membrane, made of cellulose • Found in PLANTS, FUNGI, and BACTERIA; • Not found in ANIMAL cells • Found in PLANTS, FUNGI, and some BACTERIA; • Not found in ANIMAL cells

50. ENDOCYTOSIS OF LARGE PARTICLES ENDOCYTOSIS OF SMALL PARTICLES ACTIVE TRANSPORT WHERE A CELL PACKAGES AND RELEASES CELL PRODUCTS A SOLUTION THAT HAS MORE SOLUTE (less water) THAN THE CELL A SOLUTION THAT HAS LESS SOLUTE (more water) THAN THE CELL MOVEMENT OF WATER FROM HIGH  LOW CONC. A SOLUTION WITH EQUAL CONCENTRATION OF SOLUTE TO THE CELL) MOVEMENT FROM LOW  HIGH CONC.; REQUIRES ATP MOVEMENT OF ANY MOLECULE FROM HIGH  LOW CONC A) DIFFUSION B) OSMOSIS C) ISOTONIC D) HYPOTONIC E) HYPERTONIC F) ACTIVE TRANSPORT G) EXOCYTOSIS H) PINOCYTOSIS I) PHAGOCYTOSIS Concept 9 - CELL TRANSPORT