Integument 1 Flashcards
What is the common integument?
- the outer barrier of the organism
The common integument is not just skin what else does it include?
- subcutis (AKA hypodermis/superficial fascia)
- skin = dermis and epidermis
- hair follicles and hairs
- skin glands and marry glands
- foot pads
- hooves, nails, claws
- horns and antlers
What is the subcutis?
- loose connective tissue between skin and the muscle fascia
What does the subcutis contain?
- white fat (adipose tissue)
What does adipose tissue in the subcutis provide?
- insulation
- energy source
- padding/protection (e.g., footpads)
There are regional variations in fat and thickness - describe these:
- fat accumulation such as nuchal region of horse
- local thickenings allow folds
- provide areas for subcuticular injections
What muscles are in the subcutis?
- cutaneous muscles
What are cutaneous muscles?
- thin, interrupted muscle sheets spread over the body in the subcutis allow for skin movement
Name the cutaneous muscles:
- platysma
- frontalis
- cutaneous colli
- cutaneous trunci
- cutaneous omobrachialis
- preputial
Where is the platysma located?
- over the neck and face
Where is the frontalis located and what animal does not have this?
- over the frontal bone (absent in horses)
Where is the cutaneous colli located and what animal is this muscle best developed in?
- from the sternum and spreads up neck (best developed in horses)
Where is the cutaneous trunci located?
- covers the side of the trunk - not in humans
Where is the cutaneous omobrachialis located and what animals is it found in?
- continuous of the cutaneous trunci over the shoulder and arm (ruminants and horses)
Where is the preputial muscles located and what animals it is found in?
- muscles connecting ventral midline to prepuce (carnivores, ruminants and pigs)
What is the cutis (skin) composed of?
- composed if dermis and epidermis
What does the dermis determine?
- the dermis determines the thickness of the skin
- there are regional variations
The dermis is the deep layer - what is it made up of?
- fibrous connective tissues
= few cells, not may nuclei
= collagen fibres (types 1, 3, 5)
= elastin fibres
The collagen fibres un the dermis are orientated un particular ways what are these known as?
- tension or langers lines
Why are langer lines useful?
- they make closing incisions easier
The dermis contains different regions what are these regions called?
- a superficial papillary region
- a deeper reticular region
What can regions in the dermis do?
- can project up into epidermis
- some regions have ridge-like projections (increase surface area/ contact between dermis and epidermis)
- papilla region anchors down
What components does the cutis - dermis also contain?
- blood vessels (vasodilation and constriction)
- lymphatic vessels
- nerves
- sensory receptors e.g., pacinian corpuscle
- hair follicles
- arrector pili muscles (sympathetic innervation)
- sebaceous and sweat glands (thermoregulation)
The epidermis within the cutis contains 4-5 layers what are these called?
- stratum basale (deepest)
- stratum spinosum
- stratum granulosum
- (stratum lucidum)
- stratum corneum (closes to top)
= can long giraffe spines bend