Forensics 413 Exam 2

How long does ovulation typically last

28 days

hormones in ovulation

estrogen, progesterone, FSH, LH

Estrogen

thickens uterine lining

Progesterone

maintains uterine lining after ovulation

Follicle stimulating hormone (FSH)

helps follicles grow

Luteinizing hormone (LH)

triggers ovulation

order of menstrual cycle

menstrual, follicular, ovulation, luteal

Menstrual phase

1-5, period occurs

follicular phase

1-13, FSH stimulates ovaries produce follicles which contain egg

ovulation phase

14, LH triggers ovulation and egg is released from ovary

luteal phase

15-28, progesterone maintains uterine lining until hormone levels drop or egg gets fertilized

Peripheral blood

bright red blood from veins

menstrual blood

dark red blood with clots/tissue

Presumptive tests for menstrual blood

Seratec PMB. HPLC/MS, FTIR spectroscopy

Semen composition

10% sperm, 90% fluid

Sperm morphology

head, midpiece, tail

Sperm head

contains nucleus and acrosome

Acrosome

contains hyaluronic acid which is necessary for fertilization

Sperm Midpiece

contains mitochondria for energy for motility

Sperm tail

aka flagellum, propels sperm forward

Composition of seminal fluid

enzymes (acid phosphatase), antigens (PSA), flavine (UV)

Where is seminal fluid made

10% epididymis, 15-30% prostate, 50-80% seminal vesicles

functions of seminal plasma

lubricate sperm duct, allows for travel, provides sperm nutrients, basic environment for acidic vaginal tract

spermatocytogenesis

in seminiferous tubules, initial stage of spermatogenesis where spermatogonia undergoes division to produce primary spermatocytes

spermiogenesis

final stage of spermatogenesis

morphological changes during spermiogenesis

acrosome formation, flagellum development, nuclear condensation, cytoplasmic residual bodies

development of sperm

spermatogonium, primary spermatocyte, secondary spermatocyte, spermatid, spermatozoa

cycle of sperm

• production: in seminiferous tubules

• maturation: (spermiogenesis) sperm develop tails and heads

• transport: travels through vas deferens, to ejaculatory duct, to urethra

Enzymes in acrosome (penetrate eggs outer layer)

hyaluronidase, acrosin, proteases, ATPases

semenoglobin

structural protein in seminal plasma responsible for semen coagulation after ejaculation produced in seminal vesicles

RSID

confirmatory test for semenogelin, specific for humans, cassette

Seratec (PSA) or ELISA

presumptive test for Prostate Specific Antigen, cassette

Zn2+

Sg binds to Zn2+ during ejaculation to coagulate spermatozoa into gel-like fluid

Kernechtrot-Picroindigocarmine (KPIC) / HyLiter

confirmatory test for semen, stains sperms heads and tails, microscopic analysis

Acid Phosphatase (AP)

presumptive test, catalyzes removal of phosphate group, dye group attaches to alcohols, swab stain

Vomit

matter from stomach ejected through the mouth

vomit presumptive tests

Pepsin (gastric acid), Gunzberg test for HCl

difficulties with vomit

pepsin in stomach ruins DNA quickly

feces presumptive tests

microscopic examination

where is DNA located on fecal material

epithelial cells from anus out outside edges of solid poop

types of cases with feces and/or urine

sodomy, hate crimes, aggravated mischief, animal sexual abuse

amount of urine depends on

liquid intake, temperature, physical activity, diet

organs involved with urine

kidney, bladder, ureter, urethra

kidney

filters blood and captures waste

ureter

tube connecting kidney to bladder

urethra

tube connecting bladder to outside world

main components of urine

83-95% nitrogen compounds (Urea), Creatinine, amino acids

urine presumptive tests

odor, ALS, Jaffe/uritrace, litmus paper, DMAC, RSID (THP)

ALS

urobilin in urine gives off slight UV fluorescence

Jaffe test/uritrace

presumptive test for creatinine which reacts with picric acid to form a reddish/orange product

false positives for creatinine

glucose, ascorbic acid, acetone

litmus paper test

presumptive test that uses urease enzyme to detect urea

DMAC

presumptive test for amide and amine in urea

false positives for DMAC

semen, milk, vaginal secretions

RSID (THP)

presumptive test for tamm horsefall protein (uromeodulin), non-specific for humans, specific for other body fluids

how long is sperm viable in vagina

96 hours