BiologyGuideCells & MoleculesDiseasesEcosystemHuman BiologyAQA BIOL1AQA HBIO1AQA HBIO2AQA HBIO4AQA HBIO5
Cell DivisionCell TypesCell UltrastructureEnzymesGene TechnologyGenes, DNA, RNALarge MoleculesPlasma MembraneRespiration
Video tutorials

Supplemental Videos

Click here to watch video tutorials for exam board specific videos by A* students

Cell Ultrastructure

Table 1-10-2: Microscopes (1)


Feature

Optical microscope

Electron microscope

Radiation

Light

Electrons

Magnification

400x (max1500)

≈500 000x

Resolution

2µm

1nm / 0,001µm
Electrons have a small wavelength
\ Higher resolution

Vacuum in microscope

Absent

Present

Specimen is

- Alive or dead
- Stained

- Dead (vacuum!)

Transmission microscope:
Electrons pass through internal
structure of specimen

Scanning microscope:
Beams of electrons are reflected
off specimens surface. Allows a
three dimensional view

Cell wall (plant cells only)

Nucleus (5µm)

Rough Endoplasmic Reticulum (rough ER)

Smooth Endoplasmic Reticulum (smooth ER)

Ribosomes (20-30nm)

Golgi apparatus

Vacuole and vesicles

Lysosomes (0.05 to 0.5 micron)

Mitochondria (1µm in diameter and 7µm in length)

Chloroplast (4-6µm in diameter and 1-5µm in length)