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There are three basic scale structures that make up the cuticle—coronal (crown-like), spinous (petal-like), and imbricate (flattened). Combinations and variations of these types are possible.
What is the most common scale pattern for humans?
The root of human hairs is commonly club-shaped (figure 22), whereas the roots of animal hairs are highly variable. The scale pattern of the cuticle in human hairs is routinely imbricate. Animal hairs exhibit more variable scale patterns. The shape of the hair shaft is also more variable in animal hairs.
What are the three medulla patterns?
What are the three medullary patterns? Continuous, interrupted, and fragmented.
What is the scale pattern of deer hair?
The characteristic diamond pattern is 3 to 4 scales per 100 micrometers and the flattened to vermiform scales are around 7. Deer hair has a refractive index along its length of about 1.56 and perpendicular to its length of about 1.55. It has a birefringence of about 0.01 and a positive sign of elongation.
Which pattern of scale is more common in animal hair?
Representative diagram showing different scale patterns found on hairs: a, an imbricate scale pattern is unique to human; b, spinuous; c, coronal patterns are observed on animal hairs.
What are the 3 main cuticle patterns?
There are three basic scale structures that make up the cuticle—coronal (crown-like), spinous (petal-like), and imbricate (flattened). Combinations and variations of these types are possible.
What are the 4 medulla patterns?
In the Present Study medulla has been classified into Absent, Fragmented, Discontinuous and Continuous types (Photo attached).
What three medullary patterns do animals usually display?
Medulla are generally classified as continuous, interrupted, fragmented, or absent. Human head hairs have fragmented patterns or are absent. Most animals have either a continuous or interrupted pattern.
What are some different medulla patterns?
Terms in this set (5) Continuous. one unbroken line of color. Interrupted/Intermittent. pigmented line broken at regular intervals. None. no separate pigmentation in the medulla. Fragmented/Segmented. pigmented line unevenly spaced. Solid. pigmented area filling both the medulla and the cortex.
What are the scales on hair called?
The hair cuticle is the outermost part of the hair shaft. It is formed from dead cells, overlapping in layers, which form scales that strengthen and protect the hair shaft. While the cuticle is the outermost layer, it is not responsible for the color of the hair.
What type of cuticle pattern does a horse have?
The cuticle, the outermost layer, consists of overlapping keratin scales (Deedrick & Koch 2004a) . Two main patterns of cuticle scales are: (i) imbricate, and (ii) coronal.
What is a scale cast?
Scale cast – performed by placing hair in soft medium, once it dries the hair is removes and the imprint of the scale pattern is left behind. Coronal Scale Pattern. Crown like scale pattern that resembles a stack of cups.
Does all human hair contain a medulla?
The medulla, also referred to as the pith or marrow of the hair, is the innermost layer. Composed of round cells, this layer is normally found in thick and/or coarse hair. Naturally blonde and fine hair generally does not have a medulla.
What are the three main differences between human and animal hair?
– Medulla in a human is smaller (medullary index of less than one-third); and medulla in animals is very thick (medullary index of one-half or greater). – Cuticle in humans is imbricated; and the cuticle in animals is coronal or spinous. – Pigmentation in animal hair is denser than human hair.
What are the similarities between human hair and animal hair?
What are the Similarities Between Human and Animal Hair? Both human and animal hair are made of a protein called keratin. Also, their hair contains a pigment called melanin that gives the black colour. Moreover, both human and animal hair consists of the same three parts; they are the cuticle, medulla, and cortex.
What cuticle scale pattern do cats have?
A spinous cuticle pattern was found in the rat (fancy hooded), rabbit, cat (calico), and deer. The coronal cuticle pattern was seen in the mouse (fancy), cat (tabby), and the hamster.
What can the scale pattern of a cuticle help determine?
Although scale patterns are seldom useful for characterizing human hair specimens, they are important for discriminating human hair from animal hair and for determining the type of animal from which a specimen originated.
Where do cuticle scales point?
The cuticle is the outermost layer of hair which is covered with scales. The scales point toward the tip of the hair.
What type of cuticle pattern do most animals have?
Cuticle patterns: Human hair is imbricate pattern, while animals can have a range including coronal and spinous.
What are the three types of hair?
Three Types of Natural Human Hair Terminal hair. Vellus hair. Lanugo hair.
How many medulla patterns are there?
Five different patterns of medulla are identified in forensic hair analysis.
What is the diameter of a pubic hair?
Table 1 Body regions Mean hair strand diameter (µm) Eyebrow 53.97 49.13-58.81 Axilla 76.21 69.43-82.99 Pubic 100.21 88.86-111.56.
What are the 3 medulla types?
When the medulla is present in human hairs, its structure can be described as fragmentary or trace, discontinuous or broken, or continuous. Figure 95 is a diagram depicting the three basic medullary types.
