Forensic Blood Evidence Analysis

What is the forensic value of blood as evidence?

• It is considered as both class and individual evidence.

• It is not considered as evidence.

• It is always considered as class evidence.

• It is always considered as individual evidence.

How can blood link a suspect to a crime?

• By observing the color of the blood.

• Through blood group examination and DNA analysis.

• By checking the blood's pH level.

• By measuring the temperature of the blood.

What is unique about blood stain pattern analysis?

• It is unique and has its own identity.

• It is only used in civil cases.

• It is not reliable.

• It can be substituted with other methods.

What is the purpose of presumptive tests?

• To reduce the number of samples for further testing.

• To confirm the presence of blood.

• To determine the age of the blood stain.

• To identify the exact blood group.

Which component acts as a catalyst in presumptive tests?

• Ethanol

• He

• Zinc dust

• Hydrogen peroxide

What is the main component that acts as a biomarker in blood?

• NaOH

• Zinc

• He

• Ethanol

What is the first step in the phenylene test procedure?

• Filter the solution.

• Add ethanol to the suspected stain.

• Add hydrogen peroxide to the stain.

• Prepare the stock solution.

What color indicates a positive result in the phenylene test?

• Yellow

• Pink

• Green

• Blue

What is the role of zinc dust in the phenylene test?

• It acts as a catalyst.

• It keeps the solution in a reduced state.

• It acts as an oxidant.

• It changes the color of the solution.

What is the role of hydrogen peroxide in the phenylene test?

• It acts as a reducing agent.

• It acts as an oxidant.

• It acts as a catalyst.

• It acts as an indicator.