bio sero

1. SEMEN AND ITS ANALYSIS
Submitted to
Dr. Priyanka Verma
Submitted by
Apurba - 20MFS1110
Sreya Dharan - 20MFS1111
Aathmika - 20MFS1112

2. What is semen?
Semen, also known as seminal fluid, is an organic fluid that may
contain spermatozoa. It is secreted by the gonads (sexual glands)
and other sexual organs of male or hermaphroditic animals and can
fertilize female ova. In humans, seminal fluid contains several
components besides spermatozoa: proteolytic and other enzymes
as well as fructose are elements of seminal fluid which promote the
survival of spermatozoa, and provide a azmedium through which
they can move or "swim". Semen is produced and originates from
the seminal vesicle, which is located in the pelvis. The process that
results in the discharge of semen is called ejaculation. Semen is
also a form of genetic material.

3. The mammalian sperm cell can be divided in 4 parts:
head: it contains the nucleus with densely coiled
chromatin fibres, surrounded anteriorly by an
acrosome, which contains enzymes used for
penetrating the female egg. It also contains vacuoles.
neck: it contains one typical centriole and one
atypical centriole such as the proximal centriole like.
midpiece: it has a central filamentous core with
many mitochondria spiralled around it, used for ATP
production for the journey through the female cervix,
uterus and uterine tubes.
tail or "flagellum": it executes the lashing
movements that propel the spermatocyte.

4. Semen analysis:
Semen analysis is the examinations of ejaculated seminal fluid found at crime
scene. Seminal fluid is a viscous, turbid fluid produced mainly from secretions
of seminal vesicles (45-80% of volume) and prostate gland (15-30% of the
volume ). About 10% of the total volume is the combined mixture of the
epididymis glands and bulbourrethal glands . An average male ejaculate
measures around 3.5 ml each ejaculation. Each milimetre can contain between
10 – 50 milion of sperm cell . This numbers can vary with the age of the male,
and can be negatively impacted by the medical conditions , genetic background
,diet, habit of smoking and use of illicit drugs .

5. Analysis of semen:
To naked eye seminal stains generally
appear translucent or opaque spots,
at times with yellowish tint and darker
border depending on colour and
thickness of substrata, which, if
absorbent, also acquire stiffness due
to dried semen. Semenial stains are
usually starchy when touched.

6. The acid phosphatase reaction
is a typical test in which the
suspected seminal stain or an
extract of it on a filter paper is
reacted with a solution of the
substrate, a monophenolic
phosphoric acid or its ester, in
acetate buffer of pH 5. A
negative reaction means the
absolute absence of semen.

7. Christmas tree stain test:
Two main reagents are used consecutively
to produce this distinctive stain:
Picroindigocarmine stains the neck and tail
portions of the sperm in green and blue,
while Nuclear Fast Red (also known as
Kernechtrot) gives the sperm heads a red
color and the tips of the heads, an area
known as acrosomal cap, a pink color.
Although this color pattern seems quite
unique and may render sperm cells easily
distinguishable under a microscope, sperm
cells tend to deteriorate quickly after
ejaculation.

8. p30 test:
p30 is a presumptive test for the
presence of human prostate-
specific p30 protein found in
seminal fluid. The p30 test works
through an antigen-antibody
reaction. Antibodies are present
on the p30 card and if the
antigen is present (p30 protein)
in a sample, then a reaction
occurs on the test site (T) of the
card.

9. Florence test:
• Basis: Choline is detected in this
method.
• Procedure: A few drops of watery
solution of the stain is extracted and
taken on a slide and a drop of
Florence reagent (8%) W/V solution of
Iodine in water containing 5% W/V of
Potassium Iodide) is poured & allowed
to mix slowly under a cover slip. Dark
brown crystals of choline periodide,
generally needle shaped, formed with
a few minutes. Non-specifics & false
negative results are common.

10. Barberio's test:
• Basis: Detection of Spermine
• Procedure: A few drops of Berberio’s reagent when
added to spermatic fluid produces crystals of sperm in
picrate (needle shaped, rhombic & of yellow colour).
• For various valid reasons, like non-specificity and lack of
reproducibility, the florence and berberio’s tests have not
been accepted universally.

11. References:
• Arvind Singh, Sushila Singh and Teotia, Semen Analysis,
Research News, Vol. 6, 2012.
• Richard Li, Forensic Biology: Identification and DNA
Analysis of Biological Evidences(2008).

12. THANK YOU :)