BMS Embalming and Mortuary Chemistry 4 — Questions and Answers
Question 1: A body that has been refrigerated for 10 days presents with skin slip and superficial decomposition. What is the embalmer's PRIMARY concern regarding fluid selection?
- Using a low-index fluid to avoid over-hardening
- Using a high-index fluid with added humectant and special-purpose hardening fluid (Correct answer)
- Relying solely on cavity aspiration to halt decomposition
- Applying surface embalming packs only, avoiding arterial injection
Correct answer: Using a high-index fluid with added humectant and special-purpose hardening fluid
Advanced decomposition with skin slip requires a higher formaldehyde index to achieve adequate fixation, with humectant to prevent desiccation and specialized hardeners for softened tissue.
Question 2: What chemical change causes postmortem staining (liver mortis) to become fixed and no longer shift with body position?
- Hemoglobin converts to methemoglobin and migrates into interstitial tissue
- Red blood cells lyse, releasing hemoglobin that diffuses into surrounding tissue and forms hemosiderin (Correct answer)
- Lactic acid causes coagulation of plasma proteins trapping red cells in place
- Formaldehyde released by bacteria fixes the red cells to vessel walls
Correct answer: Red blood cells lyse, releasing hemoglobin that diffuses into surrounding tissue and forms hemosiderin
After red blood cell hemolysis, free hemoglobin diffuses into surrounding tissue and is oxidized to form stable hemosiderin deposits, permanently fixing discoloration.
Question 3: What is the chemical basis for using sodium hypochlorite (bleach) as a surface disinfectant in the preparation room?
- It denatures proteins through strong alkalinity and oxidative chlorine release (Correct answer)
- It chelates heavy metals that promote bacterial growth
- It provides a lipid solvent that destroys bacterial cell walls only
- It lowers surface pH to 4.0, inhibiting microbial enzyme activity
Correct answer: It denatures proteins through strong alkalinity and oxidative chlorine release
Hypochlorite disinfects via strong oxidation from free chlorine, which oxidizes bacterial proteins and enzymes, while its high alkalinity further disrupts microbial membranes.
Question 4: During arterial embalming of an obese body, which problem is most commonly encountered due to the anatomical and chemical characteristics of adipose tissue?
- Excessive drainage making the body dehydrated
- Poor fluid distribution because fat tissue is poorly vascularized (Correct answer)
- Accelerated formaldehyde fixation due to lipid-aldehyde affinity
- Spontaneous adipocere formation within 30 minutes
Correct answer: Poor fluid distribution because fat tissue is poorly vascularized
Adipose tissue has a sparse capillary network, so arterial fluid distributed through blood vessels cannot reach deep fat deposits, leaving them poorly preserved.
Question 5: Which of the following describes the pH range considered optimal for most arterial embalming fluids?
- pH 3.0–4.5 (strongly acidic)
- pH 6.5–7.5 (near neutral to slightly acidic) (Correct answer)
- pH 8.5–10.0 (strongly alkaline)
- pH 11.0–12.0 (caustic alkaline)
Correct answer: pH 6.5–7.5 (near neutral to slightly acidic)
Arterial fluids are formulated near physiologic pH (6.5–7.5) to minimize tissue damage, optimize distribution through intact vessels, and balance fixation rate.
Question 6: What role does phenol play when used as a supplemental embalming chemical?
- Phenol acts as a surfactant to lower surface tension and improve fluid penetration
- Phenol is a caustic protein precipitant that destroys tissue on contact, used for bleaching and hardening discolored or decomposed tissue (Correct answer)
- Phenol is a chelating agent that binds iron in hemoglobin
- Phenol is a humectant that prevents tissue desiccation
Correct answer: Phenol is a caustic protein precipitant that destroys tissue on contact, used for bleaching and hardening discolored or decomposed tissue
Phenol is a caustic chemical that precipitates proteins and has bleaching properties, used carefully on decomposed, discolored, or gangrenous tissue to harden and deodorize it.
Question 7: During the saponification process in decomposition, fatty acids react with which mineral ions to form adipocere (grave wax)?
- Sodium and potassium only
- Calcium, magnesium, or sodium ions (Correct answer)
- Iron and zinc ions only
- Copper and manganese ions
Correct answer: Calcium, magnesium, or sodium ions
Fatty acids released during decomposition react with calcium, magnesium, or sodium ions in tissue fluids or soil to form the soap-like compound adipocere.
BMS Embalming and Mortuary Chemistry 4
A body that has been refrigerated for 10 days presents with skin slip and superficial decomposition.
What is the embalmer's PRIMARY concern regarding fluid selection?