Microscopy & Morphology Flashcards
What are the 4 “processes” the microbes Do?
- Nutrient Production and Energy Flow
- Decomposition
- Symbiotic relationship with humans, animals, plants.
- Human Uses
- Production of beer, yogurt
- Mass production of pesticides
- Introduce bacteria into oil spiils to clean up pollutants
What is the simplest microscopes name/the guy who found it?
What was its max magnification?
Van Leeuwenhoek
200x
What is the magnification limit for most simple light microscopes?
2000x
What are the 2 factors for light microscopy?
Magnification
Resolution
What is the magnification limit of a light microscope when looking at the size of an organism?
.2 um (200 nm)
What types of microscopy use white light?
Brightfield
Darkfield
DIC - Differntial Interference Contrast
What 2 important features make Phase Contrast a unique form of microscopy?
- Relies on phase rin which enhances difference sin light phase (gives you a white halo around the object)
- You can see intercellular structures!
What makes DIC different than Phase Contrast Microscopy?
DIC uses polarized light
What are the 3 features of Confocal Laser Scanning Microscopy?
- Uses a laser microscope and fluorescence
- Pin points focused light of only one wavelength
- Gives depth information to 3D structures
What are the differences between TEM and SEM microscopy?
- Transmission
- .2-2 nm resolution
- Can see whole cell or a cross section
- Measures electrons that pass through a sample
- Scanning
- uses electron beam to scan surfaces
- .5-10 nm resolution
What makes Atomic Force Microscopy so unique?
- Not light based
- USes cantilever which floats over surfaces and defracts a laster beam to give surface contour maps
- Very high resolution
- DNA atoms can be viewed
- 30 nm horizontally and .1 nm vertically
What are some of the reasons that different cell morphology evolved?
- Evolution Depended on ecology
- Unstable enviornments - need to reproduce quickly sphere best for SA ratio
- Stable Environment (low nutrient) - cell needs to grow slowly
- Stable High nutrient - no restrictions on reproduction rates
- Aquatic environement - need to move around - so rods, spirella, spirochete
- But we honestly don’t know!
What are the advantages to high S/V ratio and low S/V ratio?
- High - greater nutrient uptake, faster reproduction, evolution, better survival
- Low - low predation
What 2 factors determine Cell shape?
Proteins
Cell wall components
How are Archaea cell walls different thatn bacteria and Eukaryotic cell walls?
- Archeae cell walls have ether linnkages instead of ester linkages between head and tail
- Also - no fatty acids but istead have a 5-carbon hydrocarbon isproene
What are the functions of the cytoplasmic membranes?
- Prevents Leakage and diffusion into the cell
- Anchors proteins
- Procides abrrier allowing proton motive force
- Transport
- Secretion Systems
What are the repeated subunits in peptidoglycan?
NAG and NAM
What are the functions of the peptidoglycan layer?
- Connects plasma membrane and outer membrane
- Acts as a sieve
- Target of lysosomes (these break 1-4 Beta linkages)
- Anchors proteins in G+/G- and anchors lipoteichoic acids in G-
What are other morphological features of microbes?
- Glycocalyx
- capsules, slime layers
- Cellular Inclusions
- C,P, S Storage, Magnetosomes, Gas, Endospores
- Fimbriae and pili
- Flagella
- Lateral, Polar
- Cilia
What are the 2 types of cell surface structures?
- Capsules
- Polysaccharide or amino acid,
- Thick/thin
- Rigid/Flexible
- Tight matrix
- Slime Layer
- Polysaccharide
- Thick/think
- Rigid/Flexible
- SLoughed off
What is the function of cell surface structures like a slime layer?
- Aids in attachment
- Protect against osmotic stress and dessication
- Protect from predation
- protect from an immune system
What are 3 different “types” of pili?
- Bacterial Sex (F-type or P-type)
- Motility/adhesion ot srufaces (Type iV)
- Secretion (Type I)
What are the 4 types of Flagella?
- Peritrichous - flagella at numerous sites around the exterior of the cell
- Polar (monotrichous) - single flagellum at one end
- Lophotrichous - several flagella at one end
- Amphitrichous - two polar flagella, one on each end.
How much ATP is used to power the bacterial flagella?
How much ATP is used to power Eukaryotic Flagella?
No ATP is used in bacterial flagella - proton motive force.
Don’t know exact amount of ATP used in Eukaryotic.
What are the key differences between the Archaeal Flagella and the Bacterial Flagella?
- Archeae are more similar to Type IV pili
- Missing the central channel
- Growth from base, not the tip (like in bacterial flagella)
Which “domain” of cells are cilia found?
ONLY Eukaryotes
What are Cilia used for on Bacteria?
- Not found in bacteria, only eukaryotes
- For Eukaryotes
- Short, hair-like appendages
- Whip-like movement
- Some used for feeding
- Hundreds per cell
What are the different types of “swarming” or gliding on solid surfaces??
- Pili - twitching
- Fishing mechanism
- Slime Extrusion
- Shoots directionally
- Other protein based mechanism
- The tank model
