Topic 3

Question 1

Examination of semen and seminal stains is an important part in the routine investigation of sexual offense like cases of rape, adultery, sodomy, bestiality and sexual homicide.

Answer 1

SEMEN AND SEMINAL STAIN

Question 2

– this refers to a whitish fluid of the male reproductive tract consisting of spermatozoa suspended in secretion of accessory glands.

Answer 2

Semen

Question 3

Has characteristic alkaline color odor, it is viscid, gelatinous and sticky. It becomes more liquid in character when exposed to air for one and half – hour due probably to enzymatic reaction that is slightly alkaline in reaction.

Answer 3

Seminal Fluid

Question 4

– this refers to small object with a pear – shaped head behind is a short neck and then a tail of about ten times as long as the head.

Answer 4

Spermatozoa or Sperm Cell

Question 5

• arecells that come from surfaces of your body, such as your skin, blood vessels, urinary tract, or organs. They serve as a barrier between the inside and outside of your body, and protect it from viruses. A small number of epithelial cells in your urine is normal.

Answer 5

Epithelial Cells

Question 6

– one point five (1.5)ml to 3.5ml is the normal quantity of seminal fluid in a single ejaculation, 400 to 500 million is the total number of spermatozoa contained in a single ejaculate from a healthy young man.

Answer 6

Crystal of Choline and Lecithin

Question 7

, also calledPhosphatidyl Choline, any of a group of phospholipids (phosphoglycerides) that are important in cell structure andmetabolism.

Answer 7

Lecithin

Question 8

are composed ofphosphoric acid, cholines, esters ofglycerol, and two fatty acids; the chain length, position, and degree of unsaturation of these fatty acids vary, and this variation results in different lecithins with different biological functions.

Answer 8

Lecithins

Question 9

is white and waxy and darkens when exposed to air.

Answer 9

Pure lecithin

Question 10

is brown to light yellow, and its consistency varies fromplastictoliquid.

Answer 10

Commercial lecithin

Question 11

– this refers to the complete absence of spermatozoa from the ejaculate. This diagnosis must be confirmed by centrifugation of a semen specimen for 15 min at room temperature with high-powered microscopic examination of the pellet and a centrifugation speed of at least 3,000g.

Answer 11

Azoospermia

Question 12

– refers to an abnormally low concentration of sperms in the seminal fluid. Fertile semen contains about 100,000,000 sperms per ml. semen with less than about 20,000,000 sperms per ml are likely to be infertile.

Answer 12

Oligospermia

Question 13

– this refers to a condition in which there are dead or immobile spermatozoa in the semen.

Answer 13

Necrospermia

Question 14

– this is known after the name of Dr. Florence of Lysons, who first introduce it.

Answer 14

Florence Test

Question 15

test isused to detect the presence of choline, a quaternary saturated amine with the chemical formula (CH3)3N+CH2CH2OH. Choline is an essential nutrient and is found in many foodstuffs, but is particularly concentrated in meat and dairy produce.

Answer 15

Florence Iodine

Question 16

Visible/Positive Results: Crystals of Choline Periodide, which are dark brown, rhombic or needle shaped that occur singly or in cross or even grouped in cluster. It resembles haemin crystal in shape, size and color.

Answer 16

Florence Test

Question 17

: A saturated aqueous or alcoholic solution of picric acid when added to dried stain extract on a glass slide covered with a coverslip, produces yellow needle-shaped crystals of spermine picrate.

Answer 17

Barberio’s test

Question 18

Positive Results: Crystal that are slender yellow tinted, rhomboid needles with obtuse angle or appear as ovoid crystals. These crystals are made of specimen pictrate.

Answer 18

Barberio’s test

Question 19

is almost specific for human semen. The seminal stain as old as six years are said to respond to the test. This test is carried out with fresh, dried or dissolved semen.

Answer 19

Barberio’s Test

Question 20

– this test is the best way to locate and at the same time characterize a seminal stain. It has replace the Florence test in reliability and was shown to be specific for human and higher apes. The test is based fundamentally upon the extraordinary high acid phosphatase content of human male ejaculation. Phosphatase is the enzymes present in semen.

Answer 20

Acid Phosphatase Test

Question 21

Positive Results: Purple color. Purple color is indicative of Acid Phosphatase

Answer 21

Acid Phosphatase Test

Question 22

– the chief purpose of microscopic examination is to determine the presence of spermatozoa.

Answer 22

Microscopic Examination of Semen and Seminal Stains

Question 23

– the spermato – precipitins are of value in the identification of seminal fluid in certain case like for examples, beastiality when it may be desirable to differentiate between the human seminal fluid from that of an animal.

Answer 23

Biological Examination of Semen and Seminal Stain

Question 24

– this refers to examination at the scene of the crime in cases of criminal abortion, infanticide and sex offenses may lead to the discovery of bed linen, towels, chemise, skirts, mattresses and blankets, etc, which have stains.

Answer 24

Obstetrical and Gynecological Stains

Question 25

– this refers to waste materials discharge from the body especially feces. (Merriam – Webster, 1928)
Adults – Yellowish Brown
Infants – Greenish Yellow

Answer 25

Excrement

Question 26

– this refers commonly to as a pigmented coating. Paint can revel vital evidence for the forensic scientist as it is present in many surfaces.

Answer 26

Paints

Question 27

– this resemble bloodstains, reddish – brown in color, insoluble in water and soluble in dilute acid.

Answer 27

Rust Stains

Question 28

– this resembles old bloodstains but can be recognize by treating strong acids and alkaline.

Answer 28

Synthetic Dyes

Question 29

– this resembles blood that may be produced by fruits juices and vegetables.

Answer 29

Stains of Vegetable and Fruits Origin