1. Chapter 3 Cell Structure

2. Resolution: measure of clarity of an image
Section 3-1
Cell Size:
Magnification: quality of making an image appear larger than actual size
Resolution: measure of clarity of an image
e- microscopes have ↑ mag/resolution

3. Section 3-1
Light microscopes:
Form an image when light passes through 1 or more lenses to produce an enlarged image of specimen

4. Electron microscopes use beam of e- rather than light to view specimen
Section 3-1
Types of Microscopes:
Electron microscopes use beam of e- rather than light to view specimen
Live organisms can’t be viewed w/ e- microscope

5. Transmission Electron Microscope:
Section 3-1
Transmission Electron Microscope:
e- beam directed at very thin slice of specimen stained w/metal ions
e- that pass through strike fluorescent screen, forming an image; can’t view live specimen

6. Scanning Electron Microscope:
Section 3-1
Scanning Electron Microscope:
e- beam is focused on specimen coated w/ very thin layer of metal
Shows 3D details of surface of specimen; can’t view live specimen
Neutrophil (yellow) engulfing anthrax (orange)

7. e- surrounded by 48 iron atoms
Section 3-1
Scanning Tunneling Microscope:
Needle-like probe measures differences in voltage caused by e- that leak, or tunnel, from surface of object being viewed
Shows 3D details of surface of specimen
Live specimens can be viewed
e- surrounded by 48 iron atoms

8. Small cells function more efficiently than large cells
Section 3-2
Cell Size
Small cells function more efficiently than large cells
If cell’s surface area–to-volume ratio is too low, subs can’t enter/leave cell well enough to meet cell’s needs

9. 1. All LT are made of 1 or more cells
Section 3-2
Cell Theory has 3 parts:
1. All LT are made of 1 or more cells
2. Cells are basic units of structure/function in organisms
All cells arise from existing cells
All cells have:
Cell membrane
Cytoplasm
Cytoskeleton
DNA
Ribosome

10. Prokaryotic cells (bacteria):
Section 3-2
Prokaryotic cells (bacteria):
Single-celled organisms; no nucleus or internal compartments
Have cell wall, may have cilia/flagella
Have circular molecule of DNA
E. coli bacteria cell

11. Eukaryotic cells (all other LT): Nucleus contains cell’s DNA
Section 3-2
Eukaryotic cells (all other LT):
Nucleus contains cell’s DNA
Other internal compartments, organelles
Typical animal cell

12. Phospholipid made of phosphate group and 2 fatty acids
Section 3-2
Cell membrane:
Selectively permeable membrane, determines which substances enter/leave cell
Selective permeability caused by the way phospholipids interact w/ water
Phospholipid made of phosphate group and 2 fatty acids

13. Section 3-2
Proteins are embedded in the phospholipid bilayer to help move substances across cell membrane
“Outside of the cell”
“Inside of the cell”

14. Internal compartment stores cell’s DNA
Section 3-3
Nucleus:
Internal compartment stores cell’s DNA
Nucleus controls cell’s functions
Nuclear envelope is double membrane surrounding the nucleus
Nuclear pores are small openings scattered over surface of nuclear envelope

15. Structure where proteins are made Endoplasmic Reticulum (ER):
Section 3-3
Ribosome:
Structure where proteins are made
Endoplasmic Reticulum (ER):
Extensive network of internal membranes that move proteins and other subs through cell; acts as a highway

16. Carry newly made proteins through cytoplasm from ER to Golgi apparatus
Section 3-3
Vesicles:
Carry newly made proteins through cytoplasm from ER to Golgi apparatus
Golgi apparatus:
Set of flattened, membrane-bound sacs that serve as packaging/distribution center of cell

17. Mitochondria: (aka “powerhouse”)
Section 3-3
Lysosome:
Sacs of enzymes that engulf/breakdown large substances into smaller ones
Mitochondria: (aka “powerhouse”)
Organelles that convert food energy from organic compounds to make ATP
ATP:
Main energy currency of cell; “spendable”

18. Plants have 3 structures not found in animal cells:
Section 3-3
Plants have 3 structures not found in animal cells:
1. Cell Wall: support/maintain shape of cell; protects cells, connect cell to adjacent cells
2. Chloroplasts: uses light energy to make organic compds from CO2/water
3. Large Central Vacuole: stores
water, nutrients, wastes

19. Summary of Organelles:
Section 3-3
Summary of Organelles: