BMS Embalming and Mortuary Chemistry 3 — Questions and Answers
Question 1: A funeral director notices that a body shows signs of tissue gas (subcutaneous emphysema). Which organism is most likely responsible?
- Staphylococcus aureus
- Clostridium perfringens (Correct answer)
- Escherichia coli
- Pseudomonas aeruginosa
Correct answer: Clostridium perfringens
Clostridium perfringens is an anaerobic gas-producing bacterium that generates CO₂ and H₂S in tissue, causing the crepitant swelling known as tissue gas.
Question 2: What does the term 'index' (or 'strength') refer to when describing embalming fluid?
- The pH level of the solution
- The percentage of formaldehyde by weight in the diluted solution
- The percentage of formaldehyde in the concentrate (Correct answer)
- The osmotic pressure of the fluid
Correct answer: The percentage of formaldehyde in the concentrate
Index refers to the percentage of formaldehyde in the concentrated embalming fluid, not the working dilution — a 25-index fluid contains 25% formaldehyde in the stock bottle.
Question 3: During embalming, a high injection pressure is used. Which arterial complication is most likely to result?
- Insufficient preservation of distal extremities
- Purge of stomach contents through the mouth
- Rupture of fragile capillaries causing ecchymosis or distension (Correct answer)
- Rapid postmortem staining of dependent areas
Correct answer: Rupture of fragile capillaries causing ecchymosis or distension
Excessive injection pressure can rupture weakened or arteriosclerotic vessels, forcing fluid into interstitial spaces and causing swelling or purpuric discoloration.
Question 4: What is the purpose of adding anticoagulants such as EDTA to pre-injection fluids?
- To lower the formaldehyde index before injection
- To chelate calcium ions and prevent blood clot formation during drainage (Correct answer)
- To increase tissue turgor for cosmetic restoration
- To neutralize lactic acid in acidotic tissue
Correct answer: To chelate calcium ions and prevent blood clot formation during drainage
EDTA chelates calcium ions required for the coagulation cascade, keeping blood fluid and preventing clots that would block arterial distribution.
Question 5: Which of the following best explains why arterial embalming is less effective in cases of severe edema?
- Edematous tissue contains excess lipids that bind formaldehyde
- Excess interstitial fluid dilutes the embalming solution and impairs fixation (Correct answer)
- Edema raises tissue pH above 9, denaturing the preservative
- Swollen tissue compresses arteries, preventing injection
Correct answer: Excess interstitial fluid dilutes the embalming solution and impairs fixation
The large volume of interstitial fluid in edematous tissue dilutes the injected arterial solution, lowering effective formaldehyde concentration at the cellular level.
Question 6: In mortuary science, what does the term 'firming' refer to in the context of embalming results?
- The cooling of tissue to below 4°C for storage
- The hardening and gelling of tissue proteins as they cross-link with formaldehyde (Correct answer)
- The removal of excess fluid from the abdominal cavity
- The setting of cosmetic wax on surface lacerations
Correct answer: The hardening and gelling of tissue proteins as they cross-link with formaldehyde
Firming describes the palpable stiffening of tissue that occurs as formaldehyde cross-links denatured proteins, which is the intended physical result of preservation.
Question 7: Which embalming chemical class is primarily responsible for inhibiting mold and fungal growth on embalmed remains?
- Surfactants
- Humectants
- Biocides (mold inhibitors) such as thymol (Correct answer)
- Water softeners
Correct answer: Biocides (mold inhibitors) such as thymol
Mold inhibitors like thymol, quaternary ammonium compounds, or phenol derivatives are added to embalming fluids specifically to prevent fungal decomposition.
BMS Embalming and Mortuary Chemistry 3
A funeral director notices that a body shows signs of tissue gas (subcutaneous emphysema).
Which organism is most likely responsible?