6.5.1 Determining Time of Death

• What is forensic biology defined as?

  Analyzing biological evidence for crimes
• Forensic biology plays a critical role in determining the time of death
• Early post-mortem changes include rigor mortis, livor mortis, and algor mortis.
• How is entomology used in forensic biology to determine time of death?

  Analyzing insect development stages
• Forensic botany involves analyzing plant evidence to determine the time of death
• Forensic anthropology focuses on analyzing skeletal remains to determine time of death.
• What are some limitations and uncertainties in determining time of death?

  Environmental factors, individual variations
• Forensic biologists link suspects to crime scenes by analyzing biological evidence
• Which areas are encompassed by forensic biology?

  DNA analysis, blood spatter, time of death
• Match the forensic method with its description:

  Rigor Mortis ↔️ Stiffening of muscles due to chemical changes

  Livor Mortis ↔️ Settling of blood due to gravity

  Algor Mortis ↔️ Cooling of the body

  Stomach Content Analysis ↔️ Examination of food digestion stage
• Newton's Law of Cooling is used in algor mortis to calculate the body temperature
• What are the three main early post-mortem changes used to estimate time of death?

  Rigor Mortis, Livor Mortis, Algor Mortis
• Match the early post-mortem change with its description:

  Rigor Mortis ↔️ Stiffening of muscles

  Livor Mortis ↔️ Settling of blood

  Algor Mortis ↔️ Cooling of the body
• Early post-mortem changes occur shortly after death
• Late post-mortem changes include decomposition, autolysis, putrefaction, and skeletonization.
• What is autolysis in late post-mortem changes?

  Self-digestion by enzymes
• Higher temperatures accelerate the rate of decomposition
• What are the three main factors affecting the rate of decomposition?

  Temperature, humidity, oxygen
• Moist conditions enhance microbial activity
• Match the late post-mortem change with its description:

  Decomposition ↔️ Breakdown of body tissues

  Autolysis ↔️ Self-digestion by enzymes

  Putrefaction ↔️ Bacterial decomposition

  Skeletonization ↔️ Complete breakdown of soft tissues
• Order the key processes involved in decomposition:

  1️⃣ Autolysis

  2️⃣ Putrefaction

  3️⃣ Insect activity
• Autolysis involves the release of enzymes from cells.
• What are the primary byproducts of putrefaction?

  Gas, foul odors, discoloration
• Skeletonization leaves only bones
• Higher oxygen availability accelerates aerobic decomposition.
• What do late post-mortem changes help forensic biologists estimate?

  Time since death
• What are the three main areas encompassed by forensic biology?

  DNA analysis, blood spatter, time of death
• Newton's Law of Cooling is used in algor mortis to estimate time of death.
• In Newton's Law of Cooling, $T_{0}$ represents the initial body temperature
• Match the method with its description in determining time of death:

  Rigor mortis ↔️ Stiffening of muscles

  Livor mortis ↔️ Settling of blood

  Algor mortis ↔️ Cooling of the body

  Insect activity ↔️ Observation of insect development
• What are two factors that influence insect development rates?

  Temperature and toxins
• What does stomach content analysis help estimate?

  Time since last meal
• Rigor mortis is caused by ATP depletion in muscles.
• What process causes livor mortis?

  Blood pooling due to gravity
• Algor mortis involves the loss of heat
• What is the relationship between temperature and decomposition rate according to the formula?

  Decomposition rate \propto e^{\frac{ - E_{a}}{RT}}</latex>
• Accumulated Degree Days (ADD) are calculated using the formula: \sum (Daily temperature - Developmental threshold).</latex>
• According to the decomposition formula, a higher temperature speeds up decomposition
• Insect development rates can help estimate how long insects have been feeding on a body.
• Accumulated Degree Days (ADD) are used to calculate insect age in forensic entomology.