1. CHAPTER 7 SECTION 7.1: Life is Cellular

2. Robert Hooke:
Discovered cells in 1665
Looked at cork with a microscope

3. Anton van Leewenhoek looked at pond water with a microscope

4. Wee Beasties!!!

5. MOST CELLS ARE MICROSCOPIC

7. CALCULATING TOTAL MAGINIFICATION WITH THE CONPOUND LIGHT MICROSCOPE:
Power of the eyepiece lens x power of the objective lens = total magnification
Our eyepieces have a 10x lens
Our microscopes have four objective lenses:
4x _____
10x _____
40x _____
100x _____

8. COMPOUND LIGHT MICROSCOPE

9. WHAT IF WE NEED TO SEE SOMETHING SMALLER THAN THE LIGHT MICROSCOPE CAN DISPLAY?
Viruses
Organelles
Many other things
Electron microscopes!
Transmission electron microscopes (TEM) shows images of slices of specimens
Scanning electron microscopes (SEM ) shows 3D images of whole specimens

10. Liver cell
Red blood cells
mitocondrion
HIV virus

13. The CELL THEORY: All living things are made of cells Nerve cells
Skin cells
Muscle cells
blood cells
Single celled organisms (bacteria)

14. 2. The cell is the basic unit of life; all living things are made of cells

16. 3. All cells come from other cells

18. PROKARYOTES VERSUS EUKARYOTES: ALL cells have:
A plasma membrane
Cytoplasm
DNA
Ribosomes
In addition, ALL Eukaryotes have:
A nucleus
Membrane-bound organelles
All plants, animals, fungi, and protists
Prokaryotes do NOT have:
Membrane bound organelles
All bacteria

19. WHAT IS IN A CELL?
Cytoplasm
organelles

20. PROKARYOTES:

21. THE ANIMAL CELL:

22. THE NUCLEUS

25. CHROMATIN

27. NUCLEAR ENVELOPE AND NUCLEAR PORES

28. ORGANELLES THAT STORE, CLEAN UP, AND SUPPORT
Vacuoles and vesicles
Food storage: food vacuole
Water storage: large central vacuole

29. WASTE VACUOLES:
Contractile vacuoles
Removes excess water from aquatic single celled organisms
Example: Paramecium

30. Lysosomes:
Small sacs that contain digestive enzymes
Break down proteins, lipids, carbohydrates
Also break down damaged organelles
Important in ‘sculpting’ embryos

31. Vesicles

32. CYTOSKELETON: Web of proteins that: Gives the cell shape
Helps move materials within the cell
Helps the cell itself move
Made of:
Actin
Myosin
tubulin

33. Microfilaments Made of actin
Are constantly being built, broken down, and rebuilt

34. Microtubules Made of tubulin Also helps the cell keep its shape
Helps in cell division
Mitotic spindle

35. CENTRIOLES
Found in animal cells, NOT in plant cells!
Help with organization during cell division

36. CILIA AND FLAGELLA: Both allow a cell to move
Cells have one or the other, but not both
CILIA:
Many
short

37. Flagella
One or two
Long!

38. ORGANELLES THAT BUILD PROTEIN:
Ribosomes
Made of RNA and protein
Make proteins using instructions from DNA
Some ribosomes are floating free in the cytoplasm (‘free ribosomes’)
Some ribosomes are attached to the rough endoplasmic reticulum (RER)

39. ENDOPLASMIC RETICULUM:
Made of membranes
Membranes are made here
Two types:

40. Rough Endoplasmic Reticulum (RER)
Proteins are made here, on the ribosomes that are attached to the membranes
These proteins actually go inside the RER where they are modified
All proteins that leave the cell are made here

41. Smooth Endoplasmic Reticulum (SER)
Does not have ribosomes on its surface
Detoxify cells
Make membranes

42. GOLGI APPARATUS: (sometimes called Golgi ‘body’ or Golgi ‘complex’)
Formed by a stack of sacs made of membranes
Modifies, sorts, packs, and ‘ships’ molecules made by other organelles
Vesicles containing those molecules ‘bud’ off the Golgi and travel to other place inside the cell OR travel to the plasma membrane and release their molecules outside the cell

43. ORGANELLES THAT CAPTURE AND RELEASE ENERGY!
Mitochondria (found in animals AND plants!)
Chloroplasts (only found in plants)

44. Mitochondria Structure:

45. Chloroplast Structure:

46. CELLULAR BOUNDARIES: Cell walls: prokaryotes and plant cells
Provides shape
Provides support
Are OUTSIDE the plasma membrane
NOTE: cells that have cell walls also have plasma membranes: ALL cells have plasma membranes!
In plants, cell walls are made of cellulose
Cell wall

47. Cell membrane (plasma membrane)
Surrounds ALL cells!!!!
Made of phospholipids
Selectively permeable