Blood Stains: Importance & Examination

Q1) Which of the following test used to detect the blood group in an old blood stain from clothes?

a)    Benzidine test

b)    Haemin crystal test

c)     Acid dilution test

d)    Precipitin test

ANSWER- C

EXPLANATION

Benzidine test:- It is a preliminary test for blood detection. Based on the presence of hemoglobin(Hb) in blood.

Sample + Benzidine solution + H₂O₂ = intense blue colour

Haemin crystal test:- sample + sodium chloride + glacial acetic acid + heat = dark brown rhombic crystals of haemin chloride (under the microscope)

Acid dilution test:- used to detect blood group in an old blood stain from cloth.

Precipitin test:- used for differentiating human blood from other forms of blood(animal)

Q2) Which of the following methods is used for demonstration old washed-up blood stains?

a)    Luminol spray

b)    Infrared photography

c)     Ultraviolet light

d)    Magnify lens

ANSWER- A

Q3) Blood Sample for DNA fingerprinting is transported in:

a)    Saline

b)    EDTA

c)     NaF

d)    NaCl

ANSWER- B

Q4) Confirmation of menstrual bloodstain is done by the following method:

a)    Isoenzyme marker

b)    Fibrin degradation product

c)     Protein marker

d)    Restriction enzymes

ANSWER-B

Q5) Assertion (A): Bloodstains on cloth should be collected after drying in shade under room heater.

Reason(R): It causes disintegration of bloodstains.

a)    Both (A) and (R) are correct.

b)    Both (A) and (R) are incorrect.

c)     (A) is correct but (R ) is incorrect

d)    (A) is incorrect but (R) is correct.

ANSWER- D

Q6) The cherry-red discoloration of blood is due to the presence of?

a)    Carboxyhemoglobin

b)    Red hemoglobin

c)     Cyanomethaemoglobin

d)    Oxy haemoglobin

ANSWER- A

Q7) Blood group typing is a part of the following?

a)    Forensic pathology

b)    Forensic serology

c)    Forensic Odontology

d)    Criminal investigation

ANSWER- B

EXPLANATION

Forensic pathology:- the study of postmortem processes, investigations, and autopsies to determine how people die.

Forensic serology:- the study of various body fluids to detect their relationship with the criminal & crime scene.

Forensic Odontology:-study of teeth, mandible, and other teeth parts to detect several important pieces of information that help to solve the crime.

Criminal investigation:- the study of facts that are then used to inform criminal trials

Q8) The test to determine blood groups in a bloodstain is?

a)    Luminol spray

b)    Haemin crystal test

c)     Kastle-Mayer test

d)    Lattes crust method

ANSWER- D

EXPLANATION

Kastle-Mayer test:- It is a presumptive test for blood. Also known as the phenolphthalein test.

Phenolphthalein reagent + sample + H₂O₂ = Pink colour

Lattes crust method:-used to detect blood groups ABO, MNS, and Rh systems in a bloodstain.

Q9) In case of CO poisoning which preservative is recommended for the preservation of blood samples?

a)    Sodium chloride

b)    Sodium fluoride

c)     Sodium carbonate

d)    No preservative

ANSWER- D