Forensics unit 5-6 review

Cuticle

Tough, clear outside covering of the hair shaft

Coronal

Cuticle pattern looking like stacked crowns; from species such as mice

Spinous

Cuticle pattern tending to resemble petals; from species such as cats

Imbricate

Cuticle pattern with flattened overlapping scales; commonly found in human and in many animal hairs

Cortex

The middle layer of hair, made up of elongated cells containing melanin and keratin

Medulla

The spongy interior core of hair that gives it flexibility; appears as a canal in the middle of the shaft

Keratin

A fibrous protein forming the main structural constituent of hair, feathers, hoofs, claws, horns, etc

Cortical fusi

Air spaces, usually found near the root but may be found throughout the hair shaft

Anlagen phase

The initial growth phase during which the hair follicle actively produces hair. Averages 3-5 years. 80-90% of hair in this phase at any time.

Cartagena phase

The brief transition period between the growth and resting phases of a hair follicle. It signals the end of the growth phase. Lasts about three weeks. 2% of hair in this phase at any time

Telogen phase

The final phase in hair growth, resulting in the loss of hair over about three months. 8-10% of hair in this phase at any time

Follicular sheath

Hair root with skin attached; shows a struggle and may contain DNA

Fiber

Usually made up of many filaments twisted or bonded together to from a thread or yarn

Textile

A fabric made by weaving, used in making clothing

Filament

A single strand of a natural or synthetic fiber

Yarn

A continuous strand of fibers or filaments, either twisted or not

Warp

A lengthwise yarn or thread in a weave

Weft

A crosswise yarn or thread in a weave

Blend

A fabric made of two or more different types of fiber, usually as warp and weft; obvious in plaid

Fiber cross section

The cross section of a natural fiber is whatever nature provides; little can be done to change it. One exception to this rule is that the cross-section of cotton can be changed from a “flattened Lima bean” shape to nearly circular by mercerizing the textile yarn of fabric under tension. Types include: round, trilobal, dogbone, 4-lobed, octalobal, irregular, multi-lobed