Lecture 2

Question 1

Light Microscope

Answer 1

Earliest tool for cytologists, allowed identification of organelles within cells

Question 2

Organelles

Answer 2

Membrane-bound structures

Question 3

Compound Microscope

Answer 3

Microscopes with 2 lenses, increased magnification and resolution

Question 4

Microtome

Answer 4

The ‘deli-slicer’ of cell biology, allowed for the preparation of very thin slices of samples

Question 5

Staining

Answer 5

A function of the chemical properties of the substances that make up the structure, used to improve the contrast between structures similar in size and shape

Question 6

Hematoxylin

Answer 6

Positively charged/basic blue stain, binds to negatively charges/acidic structures (e.g. DNA)

Question 7

Eosin

Answer 7

Negatively charged/acidic orange-red stain, binds to positively charged/basic structures

Question 8

Tissue Microarrays

Answer 8

TMAs, chips/slides with tiny slices of many different samples (e.g. tumours)

Question 9

Limit of Resolution

Answer 9

How far appart objects must be to appear as separate objects

Question 10

Numerical Aperture

Answer 10

Refractive index of the material the light is passing through multiplied by the sine of the angle

Question 11

Phase Contrast Microscope

Answer 11

Exploits differences in the phase of light passing through a structure with a refractive index different than the surrounding medium

Question 12

Differential Interference Contrast Microscope

Answer 12

Exploits differences in the phase of light passing through a structure with a refractive index different than the surrounding medium

Question 13

Fluorescence Microscopy

Answer 13

Detects fluorescent dyes or labels to show locations of substances in the cell

Question 14

Confocal Scanning

Answer 14

Uses a laser beam to illuminate a single plane of fluorescently labeled specimen

Question 15

Fluorescence

Answer 15

Refers to the absorption of light by a molecule at a certain wavelength followed by the emission of light with a longer wavelength

Question 16

DAPI

Answer 16

A nucleophilic, DNA binding dye which appears blue

Question 17

Phalloidin

Answer 17

Green stain that binds to actin (microtubules)

Question 18

Super-resolution Microscopy

Answer 18

Use stochastic activation of fluoroscopes to differentiate between objects

Question 19

Atomic Force Microscopy

Answer 19

Image is built up by successive scans

Question 20

Electron Microscopy

Answer 20

Uses a beam of electrons rather than light to improve resolution and magnification

Question 21

Transmission Electron Microscopy

Answer 21

Electrons are transmitted through the specimen

Question 22

Scanning Electron Microscopy

Answer 22

The surface of a specimen is scanned by detecting electrons deflected from the outer surface