1. Warm Up: What are the three parts of cell theory?
All organisms are composed of cells
The cell is the structural unit of life
Cells arise only from previously existing cells

2. Cell Theory

3. The Microscope Dutch lens grinder
Invented the first compound microscope around 1600

4. The “CELL”
Robert Hooke

5. Observed cork under microscope-1655
Noted many chambers that he called “cells”
Publishes Micrographia

6. Designed his own microscope- 1683
Discovered single celled protozoan
Anton van Leeuwenhoek

7. The Cell Theory
German scientists Schleiden and Schwann develop Cell Theory
All organisms are composed of cells
The cell is the structural unit of life
Cells arise only from previously existing cells

8. Henri Dutrochet
"The cell is the fundamental element of organization"

9. In 1858, Rudolf Virchow concluded that all cells come from pre-existing cells thus completing the classical cell theory.

11. Cell Types Prokaryotic Eukaryotic “true nucleus” “before nucleus”
No membrane bound organelles
Lacks nucleus
Most unicellular organisms are prokaryotic
Monera
Eukaryotic
“true nucleus”
Membrane bound organelles
Contain nucleus
Most organisms are made of these cells
Plant cells, human cells

12. Cell Types

13. Organelles
Specialized part of the cell
“little organs”
Animal Cell

14. Plasma or cell membrane
1. Forms a thin, flexible boundary between a cell and its environment
2. Selectively permeable
-Allow some substances to pass through while keeping others out

15. Plasma membrane Phospholipid bilayer hydrophilic head-water loving
Hydrophobic tail-water fearing

16. Plasma membrane-other components
Moving with and among phospholipids
1.Proteins
2.Carbohydrates
3.Cholesterol
“Fluid mosaic”- bilayer creates a sea in which these molecules can move around

17. Plasma membrane Proteins
Receptors- proteins on outer surface that serve to transmit signals to inner cell
Structural-proteins on inner surface that serve to anchor the plasma membrane to the inner cell
Transport- proteins that span the entire membrane, moving needed substances or waste in and out

18. Plasma membrane
Cholesterol- positioned among phospholipids- helps prevent fatty acid tails from sticking together
Carbohydrates- attached to proteins, often stick out of plasma membrane- helps cell identify signals

19. Organelles within the cell-Eukaryotes
Each organelle has a unique structure and function
Allow cell to carry out essential processes

20. Cytoplasm:
clear fluid
jelly-like

21. Nuclear Structures Nucleus: Nucleolus: Nuclear Membrane:
control center
contains DNA
Nucleolus:
small dense region
makes ribosomes
Nuclear Membrane:
protects the nucleus

22. Ribosomes

23. Ribosomes
The “factories” of cells
Involved in protein synthesis

24. Endoplasmic Reticulum

25. Endoplasmic Reticulum
Extensive membrane system of folded sacs and interconnected channels- large surface area for cellular functions to take place
Continuous with outer nuclear membrane
Serves as the site for protein and lipid synthesis
Two types
Rough (ER)- has ribosomes on it that produce proteins for export
Smooth (ER)- lacks ribosomes and is involved in membrane lipid synthesis

26. Golgi apparatus Flattened stack of membranes
Modifies, sorts, and packages proteins into sacs called vesicles
Vesicles can than fuse with the cell’s plasma membrane to release proteins to the environment outside the cell or they can be used internally

27. Golgi apparatus

28. Mitochondria Powerhouse of cell Site of aerobic respiration
Sugar+oxygen ATP+carbondioxide+water

29. Lysosomes Lysosomes- found only in animal cells “Clean-up crew”
Contain enzymes for use in the breakdown of
worn-out organelles
Food particles
Bacteria and viruses

30. Centrioles Groups of microtubules that function during cell division
Usually located near the nucleus
Present in animal cells and most protists

31. Cilia and Flagella-cell movement
Some eukaryotic cells have these, composed of microtubules
Cilia- short numerous projections that look like hairs- oar like motion
Flagella- longer, less numerous-whip motion

32. What about Plant cells? Similar in many respects to animal cells
Differences
Cell wall
Chloroplasts
Vacuoles-large

33. Cell Wall Thick, rigid, mesh of cellulose fibers
Rigid cell walls allow plants to stand at great heights

34. General Sherman- largest living thing

35. Chloroplasts Site of Photosynthesis
Converts solar energy to chemical energy-ATP and sugars
Chlorophyll: green pigment which captures light

36. Vacuoles Membrane bound vesicle
Used to store food, waste products, enzymes, and other materials needed by the cell
Some animal cells contain vacuoles- they are much smaller than those in plants

37. Comparing Plant & Animal Cells
Structure
Animal ?
Plant?
cell membrane
cell wall
nucleus
ribosomes
E.R.

38. golgi
lysosomes
vacuoles
mitochondria
chloroplasts

39. Comparing Plant & Animal Cells
Structure
Animal ?
Plant?
cell membrane
Yes
cell wall No
nucleus
ribosomes
E.R.

40. golgi
Yes
lysosomes No
vacuoles
Small
Large
mitochondria
chloroplasts

41. Cellular Transport
Moves substances within the cell and moves substances into and out of the cell
Diffusion/osmosis
Facilitated diffusion
Active transport

42. Diffusion Random motion from high concentration to low
No energy required
Rate of diffusion is affected by
Concentration
Temperature
Pressure

43. Osmosis The diffusion of water across a selectively permeable membrane
If cell is in a solution that has a lower concentration of solute/water=hypotonic
If cell is in a solution that has a higher concentration of solute=hypertonic
If cell is in a solution that has an equal concentration of solute=isotonic

44. Facilitated Diffusion
Uses transport proteins to move ions and small molecules across the plasma membrane
Uses concentration gradient for energy
Conformational change in protein allows passage

45. Active Transport Moves substances against concentration gradient
Accomplished by protein pumps
Na+/K+ ATPase pump is an example
Requires energy(ATP)

46. Transport of Large Particles
Endocytosis- cell surrounds a substance with plasma membrane- pinches it of to form vacuole
Exocytosis- cell releases a substance at plasma membrane
Both processes require energy(ATP)