The common integument

Question 1

Common integument

Answer 1

ordinary skin with its covering of hair and variety of skin glands as well as more specialized parts such as claws, hoofs and horns.

Question 2

Roles of the skin

Answer 2

• Covers the body and protects it from injury.
• Temperature control
• Enables the animal to respond to various external stimuli

Question 3

3 types of hair

Answer 3

• Guard hair
• Wavy wool hair
• Tactile hair

Question 4

Layers of skin

Answer 4

• Epidermis (out)
• Dermis (in)
• These rest on a loose connective tissue named: Subcutis, hypodermis, superficial fascia

Question 5

Guard hairs

Answer 5

• Straight, rather stiff
• “Topcoat”
• lie close against the skin and sweep uniformly in broad tracts; giving the coat a smooth appearance disturbed only by the whorls and crest.

-Promotes the run off of rain. Preventing chilling if water made contact with skin

• Occasionally, animals are born with a disturbed coat pattern which may seriously impair their ability to withstand severe weather

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Question 6

Wool hairs

Answer 6

• Fine, thin
• Provide soft Undercoat
• wavy
• shorter and more numerous than the guard hair
• concealed between the guard hairs

Question 7

Tactile hairs

Answer 7

• substantially thicker
• generally protrude beyond the neighboring guard hairs and reach deep into the subcutis or even the superficial muscles
• characterized by the presence of a venous sinus filled with blood and located between inner and outer layers of the dermal sheath.
• restricted distribution
• associated with touch receptors
• nerve ending responsive within the dermal sheath
• example: whiskers

Question 8

Hair structure

Answer 8

• Cuticle
• Cortex
• Medulla

Question 9

Melanin

Answer 9

• Responsible for color of hair
• Pigment produced in a special group of cells known as melanocytes. It also colors the skin.

Question 10

Follicle

Answer 10

• tiny pit where hair grows to protrude above the surface of the skin
• develops from a ectodermal bud

Question 11

Topography of tactile hair

Answer 11

• Face
• Principally on the upper lip and about the eyes
• Although other are scattered (in species-variable fashion) on the lower lip, the chin, and elsewhere on the head

Question 12

Tactile hair functionality

Answer 12

• nerve endings responsive to mechanical stimulation
• the stimulus provided by disturbance of the hair is amplified by wave motion in the blood

Question 13

Tactile hair development

Answer 13

• follicles of tactile hairs appear in early development before those of the coat hairs.

Question 14

Torus/Tori

Answer 14

Torus (singular) and Tori (plural)

• a bulging or rounded projection or swelling
• Torus- used in connection with the common integument, detonates a pad
• it includes the thick epidermal covering, the dermis, and the subcutaneous cushion or pulvinus

Question 15

Pulvinus

Answer 15

subcutaneous cushion

Question 16

Footpads structure

Answer 16

• naked, densely cornified epidermis
• dermis is unremarkable

-thick, resilient subcutis

-admixture of collagenous and elastic fibers interspersed with adipose tissue (fat)

• footpads are the digital cushion on which animals walk

Question 17

Plantigrade

Question 18

Digitigrade

Question 19

Ruminants and pigs digital pads

Answer 19

bulb

Question 20

Horses digital pads

Answer 20

frog

Question 21

Nails, claws and hoofs

Answer 21

• similar structures enclosing the distal phalanx appear strikingly different
• local modification of skin
• Serve primarily to protect the underlying tissues

Question 22

What are Nails, claws and hoofs used for?

Answer 22

• Scratching
• Digging
• Weapon
• Grab the food