Session 1 - Investigative Techniques

Question 1

Describe Robert Hooke and his discovery.

Answer 1

• First to use a microscope
• First examined a sample of dead cork; thought the squares looked like Monk cellula; this is where the term cell originated

Question 2

What 3 types of cells live independently/individually?

Answer 2

Ovum, Sperm, and Blood Cells

Question 3

What are the requirements to image tissues by light microscopy?

Answer 3

Preservation via Formalin to prevent rotting of sample
Embed via paraffin wax to allow sample to be thinly sliced
Stain via Hematoxylin (nucleus blue) and Eosin (cytoplasm and ECM pink) stain to all observation of the cell components

Question 4

Describe the steps involved in freezing a section/sample. What are the pros and cons of this method vs. the traditional histology technique?

Answer 4

• Surgical specimen placed on metal disc and frozen to -20 to -30 degrees celcius.
• Tissue becomes rock hard
• Cryostat (essentially microtome in a freezer) is used to cut frozen specimen
• Staining then occurs with H&E stain.
• Pro: Quicker process (10mins vs. 16hours)
• Con: Technical quality is much lower

Question 5

What happens to light in a polarised light microscope?

Answer 5

Travels in one direction only.

Question 6

How does Gout differ from Pseudo Gout?

Answer 6

Gout

• High serum uric acid usually present (although not always)
• Presence of Monosodium Urate crystals which appear yellow under light microscope
• Main joint affected is the big toe (metatarsal phalangeal joint)

Pseudo Gout

• Blue crystals under the microscope
• Presence of Calcium Pyrophosphate dihydrate crystals which appear blue light microscope