Latte’s crust of blood stain is used to detect ?
Correct Answer: Blood group
Description: Ans. is 'c' i.e., Blood group Blood and blood stains The examination of blood and blood stains is an impoant pa of crime detection. The points that are usually required to be determined regarding stains are : (1) nature of stain (whether the stains is blood or not); (2) the species (human or animal) from which the blood has come from; and (3) blood group. Nature of stain (whether the stain is blood or not) To determine the nature of stain, following tests are used : 1. Chemical tests These tests are based on the peroxidase activity of haematin, which is, derived from oxidation of haem of haemoglobin or methemoglobin, present. This enzyme, in the presence of hydrogen peroxide conves colourless salts into coloured bases. Thus these tests are based on H202 and peroxidase enzyme. Tests are : Benzidine test: Greenish blue colour. Phenolphthalein test (kastle myere test) : Deep permanganate colour. Leucomalachite green test : Bluish green or peacock blue colour. Guaiacum test : Blue colour. Ohotoludine test (kohn test) : Blue or green colour. Amidopyrine test : Purple colour. 2. Microchemical tests These tests are based on propey of haem pa of hemoglobin to form characteristic coloured crystals. The tests are : Teichmann's haemin crystal test. Takayama hemochromogen crystal test. Luminal spray test : It is especially useful in old obscure blood stains. Spetroscopy It is most delicate and reliable test. It is based on the principle that hemoglobin and its derivatives give characteristic absorption bands when viewed through a spectroscope. 4. Microscopy Microscopic examination of RBCs is possible only in fresh stains. Detection of species (whether the blood has come from human or animal) For detection of species, serological (immunological) tests are used. These tests are : Precipitin test Haemaglutination inhibition test (antiglobulin consumption test or absorption inhibition test). Gel diffusion test. Double diffusion test. Precipitation electrophoresis. Latex agglutination test. Isoenzyme method (enzymological test). Detection of blood group of blood stain These tests are : Immunological (serological) : (i) aborption-elution test, (ii) absorption-inhibition test, (iii) mixed agglutination test, (iv) latex test. Enzymological methods. Latte's crust method.
Category:
Forensic Medicine
Get More
Subject Mock Tests
Practice with over 200,000 questions from various medical subjects and improve your knowledge.
Attempt a mock test nowMock Exam
Take an exam with 100 random questions selected from all subjects to test your knowledge.
Coming SoonGet More
Subject Mock Tests
Try practicing mock tests with over 200,000 questions from various medical subjects.
Attempt a mock test now