Forensic Science: Blood Analysis

Introduction to Blood Analysis in Forensics

• Blood analysis is a crucial part of forensic science.
• It helps in identifying suspects and understanding crime scenes.

Composition and Function of Blood

• Blood is composed of red blood cells, white blood cells, platelets, and plasma.
• Functions:
  • Red blood cells transport oxygen.
  • White blood cells fight infections.
  • Platelets aid in blood clotting.
  • Plasma carries nutrients, hormones, and waste products.

Blood Typing and Its Importance

• Blood typing is essential for transfusions and crime scene investigations.
• Blood types:
  • A, B, AB, and O.
  • Positive or negative Rh factor.

Blood Spatter Analysis

• Helps determine the position and movement of a victim and assailant.
• Patterns analyzed:
  • Shape and size of blood droplets.
  • Distribution and angle of impact.

Techniques in Blood Analysis

• Presumptive Tests:
  • Luminol tests for detecting trace amounts of blood.
  • Kastle-Meyer test uses phenolphthalein to indicate blood presence.
• Confirmatory Tests:
  • Microscope analysis for cellular components.
  • DNA analysis for conclusive identity matching.

Challenges in Blood Analysis

• Contamination of samples.
• Degradation over time and environmental factors.
• Differentiating between human and animal blood.

Case Studies

• Historical cases where blood analysis was pivotal in solving crimes.

Conclusion

• Blood analysis remains a vital tool in forensic investigations.
• Continual advancements in technology enhance accuracy and reliability.