1. Cells
Unit 4

2. Development of Cell Theory
Anton van Leeuenhoek -1600’s ,developed 1st microscope. Saw tiny things in a drop of water.
Robert Hooke- looked at cork. Saw tiny squares that looked like the monks rooms- called them cells. Actually saw the plant cell wall.
Robert Brown- first to see cell nucleus

3. Matthias Schleiden- proved all plants were made of cells
Theodor Schwann- proved all animals made of cells
Rudolf Virchow- showed that cells come from other cells dividing.
Ideas led to………

4. The Cell Theory All living things composed of cells
Cells are basic unit of structure
All cells come from pre existing cells.

5. Microscopes Compound Light M.- uses light. Can magnify up to 1000x.
Electron microscopes- uses beam of electrons. Specimen must be viewed in vacuum( no air- so specimen dead!)
Scanning EM- scans the surface- gives 3D picture
Transmission EM- can see inside cell.

6. 2 Types of cells
Prokarotes
Eukaryotes

7. Prokaryotes Do not have membrane bound organelles: no nucleus.
Bacteria

8. Eukaryotes Have membrane bound organelles: like a nucleus.
Animal cell, plant cell

9. Cell structure
Cells come in many different sizes and shapes because of the function they carry out.

10. Properties of All Cells
Obtain food for energy
Excrete wastes
Make new living material(growth)
Reproduce

11. Plasma Membrane

12. Function
Controls the internal environment of a cell- decided what moves in and out
Maintains homeostasis

13. Selective permeability
allows some molecules to pass through membrane (SEMI PERMEABLE)
Molecules can pass through membrane or pass with aid from membrane proteins

14. Structure PHOSPHOLIPID(sub unit) Glycerol + 2 FA chains+P
Phosphate head
Fatty Acid tail
Hydrophilic head
Hydrophobic tail

16. Fluid Mosaic Model
Phospholipid bilayer- 2 rows of phospholipids with the tails facing each other (pg 177)
Phospholipids moveable
Mosaic- made of different parts-
Membrane proteins-transport materials through,also act as cell receptors for recognition
Cholesterol-helps keep fatty acid tails from sticking together- helps maintain fluidity

18. Cell structure with a specific function and shape
ORGANELLES
Cell structure with a specific function and shape

19. CELL WALL Found in plant cells Provides rigidity and strength
Made of cellulose
Pectin glues the cells together

20. NUCLEUS Controls cell functions
Surrounded by nuclear membrane(has pores)
Contains DNA (chromatin ) has instructions(genes) for all cell metabolism like making proteins
Chromosomes are made of long strands of chromatin that are condensed

21. NUCLEOLUS
Found inside the nucleus
Makes ribosomes

22. RIBOSOMES Made of RNA Site of protein production Not membrane bound
Found in the cytoplasm(free)
And also on the RoughER (bound)
Made of RNA

23. CYTOPLASM Clear gelatinous fluid inside cell Suspends the organelles
Site of metabolic reactions

24. ENDOPLASMIC RETICULUM
Folded membrane
Rough ER has ribosomes attached-make proteins that are used oustide of the cell
Unbound ribosomes make proteins used inside the cell
Act as transport channels to move material within the cell
Packages proteins in small vessicles to move to Golgi

25. Golgi Apparatus Flattened stack of membranes
Modifies proteins-specializes them
Packages proteins so they can leave the cell

26. VACUOLES Compartments used for temporary storage
Can store waste, food, enzymes
Plant cell has 1 large vacuole to store water

27. Plastids Found in plants Used to store food and pigments
Plastid that store pigment is a chromoplast
(chlorophyll/chloroplast)

28. LYSOSOME Only found in animal cells Contains digestive enzymes
Digest worn out cell parts, food, engulfed bacteria and viruses
Membrane surrounding lysosome prevents leakage of digestive enzyme into cytoplasm where it would self- digest the cell
Can fuse with food vacuole to digest food.
What would happen to a cell if the lysosomes burst?

29. CHLOROPLAST Only found in plant cells
Capture light energy and turn it into chemical energy
Contains chlorophyll
3 parts:
thylakoid-disc granum-stack stroma-inner space

30. MITOCHONDRIA Power house of the cell Makes ATP Adenosine Triphosphate
# of mitochondria depend on energy needs of cell-ex. Muscle cells have a lot!
Glucose is changed to ATP at the inner folds(cristae)
Cellular Respiration

31. CYTOSKELETON Microtubules and Microfilaments
Microtubules- hollow
Microfilaments- solid- function in cytoplasmic streaming
Made of proteins
Provide internal support
Acts like scaffold
Also like a highway in the cell to move materials

32. Centrioles Found in animal cells only
Aids in forming the spindle fibers used during cell division(mitosis)
Made of microtubules

33. CILIA AND FLAGELLA Made of microtubules
Cilia- short hair like fibers used for locomotion (paremecium)
Flagella- long whip like structure used for locomotion

34. Transportation of Materials
THE CELL
Transportation of Materials

35. Movement of Materials The cell membrane is SEMI PERMEABLE:
allows movement of some things in and out
Diffusion- movement of materials across a membrane
Osmosis- movement of WATER across a membrane
Cells want to be at equilibrium(Homeostasis)

36. TYPES OF DIFFUSION PASSIVE- requires no energy- moves high to low
FACILITATED- membrane proteins or carrier molecules help materials cross the membrane. They can’t cross on their own.
ACTIVE- energy required- moves low to high(you are pushing more into the cell)

37. PASSIVE DIFFUSION

38. FACILITATED DIFFUSION

39. ACTIVE DIFFUSION

40. Hypotonic- cell or solution has less molecules
Hypertonic- cell or solution has more molecules
Isotonic- cell or solution has equal molecules

41. Cell shrinks and shrivels
Animal Cell
Type
Movement of Water
Fate of Cell
Picture
HYPOTONIC
Into cell
Cell swells and bursts
HYPERTONIC
Out of Cell
Cell shrinks and shrivels
LYSES
ISOTONIC
No net change
HOMEOSTASIS

42. ANIMAL CELL

43. PLANT CELL

44. Movement of large material across cell membrane-requires energy
Endocytosis- cell surrounds material and
engulfs it.
Phagocytosis: taking in a solid
Pinocytosis: taking in a liquid

46. cell expels material EXOCYTOSIS 1. Material contained in a vacuole
2. Vacuole moves toward outer edge
3. Vacuole opens up to outside and releases material