BMS Embalming and Mortuary Chemistry 2 — Questions and Answers
Question 1: Which chemical reaction is primarily responsible for the cross-linking of proteins during formaldehyde embalming?
- Oxidation of sulfhydryl groups
- Methylol bridge formation between amino groups (Correct answer)
- Saponification of fatty acids
- Hydrolysis of peptide bonds
Correct answer: Methylol bridge formation between amino groups
Formaldehyde reacts with free amino groups on proteins to form methylol intermediates that bridge adjacent protein chains, creating cross-links that firm tissue.
Question 2: A body with a blood pH of 5.8 due to acidosis will require what embalming fluid adjustment?
- Decreased formaldehyde concentration
- Increased buffer content in arterial fluid (Correct answer)
- Addition of humectant only
- Reduced injection pressure
Correct answer: Increased buffer content in arterial fluid
Acidotic tissues consume aldehyde rapidly and resist preservation, so buffered arterial fluid helps neutralize acid and stabilizes fixation chemistry.
Question 3: What is the primary purpose of using a co-injection fluid alongside arterial embalming solution?
- To increase the index of the arterial fluid
- To condition the vascular system and improve fluid distribution (Correct answer)
- To prevent rigor mortis from forming
- To sterilize surface bacteria on the skin
Correct answer: To condition the vascular system and improve fluid distribution
Co-injection fluids contain surfactants, anticoagulants, and conditioners that open capillaries and improve even distribution of the primary arterial solution.
Question 4: Cavity embalming fluid typically contains a much higher index of formaldehyde than arterial fluid. What is the typical range for cavity fluid index?
- 5–10 index
- 15–30 index
- 35–50 index (Correct answer)
- 1–4 index
Correct answer: 35–50 index
Cavity fluids generally range from 25–50 index because they must penetrate and fix organ masses that are not reached by the vascular system.
Question 5: Which embalming complication arises when excessive amounts of humectant cause tissues to remain too moist and soft after embalming?
- Desquamation
- Over-embalming
- Formaldehyde gas burn
- Waterlogging (Correct answer)
Correct answer: Waterlogging
Waterlogging occurs when hygroscopic humectants draw and retain too much moisture, leaving tissues swollen, soft, and poorly preserved.
Question 6: In mortuary chemistry, what is the function of a 'modifying agent' added to arterial embalming fluid?
- To increase the pH of the solution above 9
- To slow or adjust the rate of formaldehyde fixation (Correct answer)
- To replace formaldehyde as the primary preservative
- To lyse red blood cells for easier drainage
Correct answer: To slow or adjust the rate of formaldehyde fixation
Modifying agents such as methanol or certain alcohols regulate how quickly formaldehyde fixes tissue, preventing over-hardening or uneven preservation.
Question 7: Which chemical property of glutaraldehyde makes it a more potent cross-linker than formaldehyde?
- It is a monoaldehyde with a small molecular weight
- It is a dialdehyde capable of bridging two protein chains simultaneously (Correct answer)
- It has a higher water solubility than formaldehyde
- It reacts exclusively with lipids rather than proteins
Correct answer: It is a dialdehyde capable of bridging two protein chains simultaneously
Glutaraldehyde's two reactive aldehyde groups allow it to bridge proteins on both ends simultaneously, creating denser cross-links than single-ended formaldehyde.
BMS Embalming and Mortuary Chemistry 2
Which chemical reaction is primarily responsible for the cross-linking of proteins during formaldehyde embalming?