Textbook Notes (280,000)
CA (170,000)
Queen's (4,000)
BIOL (200)
BIOL 102 (100)
Chapter 6

BIOL 102 Chapter Notes - Chapter 6: Transmission Electron Microscopy, Scanning Electron Microscope, Endoplasmic Reticulum


Department
Biology
Course Code
BIOL 102
Professor
Dr. W.A. Snedden
Chapter
6

This preview shows page 1. to view the full 4 pages of the document.
CHAPTER SIX
Microscopy
- Light microscope- visible light is passed through the specimen and then through
glass lenses
o Lenses refract the light to magnify the specimen
o Shows subcellular localization
o Nucleus is blue, mitochondria is orange, cytoskeleton is green
- Magnification- ratio of an object’s size to its real size
- Resolution- clarity of an image
- Contrast- the difference in brightness between the light and dark areas of an image
- Electron microscope- focuses a beam of electrons through a specimen or onto its
surface, very good magnification
- Scanning electron microscope- used for the detailed study of the topography
(surface) of a specimen
- Transmission electron microscope- to study the internal structure of cells
Bacterial Cell
- DNA is concentrated in a non-membrane-closed region called the nucleoid
- Eukaryotic cells are more specialized and organised
- Ribosomes- synthesize polypeptides
- Plasma membrane- phospholipid bilayer that encloses cytoplasm
- Cytoplasm- site of metabolism
- Pili- allow cells to attach to other surfaces and each other
- Flagella- tail that allows bacteria to swim
- Glycocalyx- outer gelatinous covering
- Cell wall- support and protection
Eukaryotic Cell
- More organised, has membranes that partition the cell
- Endoplasmic reticulum- membrane synthesis and other synthetic processes
o Rough has ribosomes, smooth doesn’t
- Nuclear envelope- double membrane surrounding nucleus,
porous, is attached to ER
- Nucleolus- makes ribosomes, doesn’t have a membrane
- Chromatin- consists of DNA and proteins
- Plasma membrane- encloses cell (no cell wall)
- Ribosomes- make proteins, in ER, nuclear envelope or cytosol
- Golgi apparatus- making, sorting, and shipping of cell products
You're Reading a Preview

Unlock to view full version