integument

Question 1

integument

Answer 1

(AKA skin)

covers entire animal, includes sweat and oil glands, hair, nails, horns

Question 2

integument function

Answer 2

protective (microbes, insects, parasites, environment, chemical, UV, physical)
- preventing dehydration
body temp regulation 
- detecting sensory info
synthesis of vit D
- food gathering (claws)

Question 3

characteristics of the skin

Answer 3

covers external surface of animals, can heal and regenerate. human skin replaced every 4-7 weeks.
loosely attached to enable movement w/o tearing
thickest where commonly exposed (elbow vs between fingers)

Question 4

layers of the skin

Answer 4

epidermis
dermis
hypodermis

Question 5

location of blood cells in integument?

Answer 5

mostly in the hypodermis, w little trails up to the dermis.

no blood in epidermis

Question 6

epidermis

Answer 6

layer of flat cells, free of nerve endings, gets nutrients through diffusion from the dermis. 
basal layer (closest to dermis) mostly keratin, cells migrate up where they then kinda shed off.

Question 7

kertatinization

Answer 7

keratin to epithelium, cornification where superficial cells to stratified epithelium along w hardening and release of glycolypids which slow water loss

Question 8

function of hertatin

Answer 8

makes skin tough and resistant to drying out

Question 9

desmosomes

Answer 9

anchors, connects keratinocytes to form a more protective barrier

Question 10

melanocites

Answer 10

produces pigment, melanin which protects against UV radiation

Question 11

merkel cells

Answer 11

sensory receptors to light touch

Question 12

langerhan’s cells

Answer 12

phagocytes foreign debris or microorganisms

- immune cell type

Question 13

dermis

Answer 13

middle layer
has palpable that projects into the epidermis where they interdigitate w the epidermal projections to cement the 2 layers together
makes up most of the integument
AKA Corium

Question 14

relationship between epidermis and dermis

Answer 14

folds project down into the dermis

Question 15

functions of the dermis

Answer 15

• structural strength and flexibility of the skin (bc of collagen and other fibres)
• presence of blood vessels (gives nutrients to epidermis)
• sensory receptors (sends info to CNS)

Question 16

hypodermis

Answer 16

under the dermis
AKA subcutaneous fat layer
allows skin to move over underlying muscle and bone w/o tearing
cushions and protects skin and underlying muscles and organs

Question 17

senses in the hypodermis

Answer 17

pacinian corpuscles - touch receptors that respond to heavy pressure and vibrations

Question 18

blood vessels in the hypodermis

Answer 18

helps w milk production

Question 19

2 types of sweat glands

Answer 19

eccrine and apocrine

in dermis and hypodermis

Question 20

what type of glads do farm animals have

Answer 20

apocrine - open into sweat glands

produce secretion w water, fatty acids and proteins combined w gland secretions for the smell

Question 21

eccrine sweat glands

Answer 21

in primates, secretes mix of water, salts, primary function to cool the body

Question 22

apocrine glands species differences

Answer 22

horses only animal w large amounts of sweat
bos tarus vs bos indicus, indicus (w the hump) much larger # of sweat glands
pigs dont sweat

Question 23

oil glands

Answer 23

found all over the body in the dermis, secretes onto the skin surface
oil glands produce sebum
oil glands used to mark territories and attract mates in some species

Question 24

sebum

Answer 24

like lanolin, keeps hair from being brittle, prevents excess evaporation. keeps skin soft

Question 25

hair/pilli function

Answer 25

insulation, absorbs light to warm animals, protection via camouflage, also a legit layer
sensory receptors
depends on # and size of follicles on the skin

Question 26

hair production

Answer 26

occurs at the base of follicle
covered by rapidly dividing cells called the matrix.
get pushed away from papilla and die from lack of nutrients.
layers of dead skin. fun

Question 27

guard/primary hair

Answer 27

forms smooth outer coat

Question 28

undercoat

Answer 28

wool hairs (soft and curly) sheep have no guard hairs so their wool is long and fine

Question 29

innervated tactile hairs

Answer 29

organs of touch (whiskers)

Question 30

feathers

Answer 30

function to protect against elements, enable flying, maintain body temp, protect from predators, attraction

Question 31

ungulate

Answer 31

hoofed animal, use tips of toes to sustain entire body weight

Question 32

what is a hoof anatomically

Answer 32

extension of skin from lower limbs covering distal digit

Question 33

why shoe horses

Answer 33

increase integrity of hoof wall
increase traction
strengthens foot
prevents expansion of the hoof
protective barrier between hoof and ground

Question 34

horns

Answer 34

over corneal process in frontal skull bones
horn core found on frontal bone
elongates from the base, cells considered epidermal cells
made up of dense keratin similar to hoof wall and hair

Question 35

what influences horn growth

Answer 35

nutrition
sex
species
genetics