Zusammenfassung der Ressource
OCR: AS Biology: F211
- Microscopy
- Resolution
- Definition
- How well it can
distinguish between two
points close together
- Light Microscope
- 200nm
- TEM
- 0.1nm
- SEM
- 0.1nm
- Magnification
- Light Microscope
- x1500
- TEM
- x500,000
- SEM
- x100,000
- Definition
- How much bigger
the image is than
the specimen
- Staining
- Used with light
microscope
- Chemicals bind to
specimen, allowing
it to be seen
- Some bind to
specific structures
- Makes recognition easier
- Acetic orcein
staining DNA red
- EM create black
and white images
- Dipped in heavy
metals (e.g. lead)
- Creates a contrast
- Cell Structure
- Membranes
- Fluid Mosaic Model
- Phospholipid Bilayer
- Hydrophilic
tail
- Hydrophobic
head
- Small, non-polar
substances
diffuse through
- Cholesterol
- Lipid
- Membrane
stability
- Binds to
tails so it's
less fluid
- Proteins
- Control what
leaves/enters
cell
- Channel Proteins
- Smaller ions
and polar
molecules
- Used in diffusion
- Sometimes
facilitated
- Carrier Proteins
- Facilitated
diffusion
- Large molecules
and ions
- Down concentration gradient
- Active Transport
- Against concentration gradient
- Uses ATP
- Glycolipids/
Glycoproteins
- Cell Signalling
- Hormones bind
to complimentary
receptor
- Communication
between cells
- Antigens
- Cell Surface
- Plasma
membranes
- Partially
permeable
- Allow
substances to
move in and out
- Within cells
- Separate organelles
- Folded- increase surface area
- Vesicles to transport substances around
- Organelles
- Nucleus
- Prokaryotic VS Eukaryotic
- Breathing
- Transport: Animals
- Transport: Plants
- Cell Division