Integument

Question 1

What is the integument

Answer 1

-one of the largest and most extensive organ system in the body
- it covers the entire animal

Question 2

what does the integument include

Answer 2

-skin
-sweat and oil glands
- hair
-hooves / horns

Question 3

functions of the integument

Answer 3

-protects the body
- physical abrasion
-dehydration
- maintenance of body temperature
- detection of sensory information
- transfer the information to central nervous system
- excretion of organic waste and excess salts
-metabolic actions
-synthesis of vitamin d

Question 4

Skin (hide)

Answer 4

• covers the outside of the animal
• has the ability to regenerate and heal
  -skin thickness may differ between species
• is thickest in regions where it has greatest exposure to the environment

Question 5

what are the 3 layers of the skin

Answer 5

• epidermis
• dermis
• hypodermis

Question 6

epidermis

Answer 6

• formed by layers of flat cells
• made up of stratified squamous epithelium
• there are no blood vessels found in this layer
• is generally free of nerve endings

Question 7

what is only found in non hairy animals

Answer 7

stratum lucidum and stratum granulosum

Question 8

4 layers of epidermis

Answer 8

• stratum basale
• stratum spinosum
• stratum granulosum
• stratum corneum

Question 9

stratum spinosum

Answer 9

• the cells as polyhedral to slightly flattened
• this layer is arranged in 2-4 layers depending on the species

Question 10

stratum granulosum

Answer 10

-composed of flattened cells with a shrunken nuclei
- contains a keratin granules - precursors for keratination process

Question 11

stratum corneum

Answer 11

• provide a removal of surface pathogens
• contains antimicrobial peptides and lipids
• aid in bacterial and chemical defense

Question 12

what happens in the epidermis?

Answer 12

-as daughter cells and produced, they push older cells to the surface of the epidermis
- it prevents the older cells to obtaining adequate nutrients
- older cells flatten, die and undergo changes including the loss of nuclei, cytosol and organelles

Question 13

what is the process of keratinization and hardening?

Answer 13

• the cells exposed to the environment dry out and become harder
• while these keratinized cells are dead, the keratin has a protective function to make the skin tough and resilient

Question 14

What other types of cells are in the epidermis?

Answer 14

• langerhan cells
  -melanocyte
• merkell cell

Question 15

langerhan Cells

Answer 15

detects invaders such as forein debris or microorganisms and phagocytize them

Question 16

Melanocyte

Answer 16

responsible for producing the pigment, melanin which protects cells from ultraviolet radiation

Question 17

merkell Cell

Answer 17

function as sensory receptors to touch and are found at the epidermal/dermal junction

Question 18

Dermis

Answer 18

• seperated by the epithelial basement membrane
• makes up about 80% of the total mass of the skin
  -composed of dense irregular connective tissue
• has a rich tissue community
  -presence of blood vessels and sensory receptors

Question 19

functions of the dermis

Answer 19

• provides structural strength and flexibility of the skin

Question 20

hypodermis

Answer 20

• also known as subcutaneous fat layer

Question 21

what is the hypodermis made up of?

Answer 21

• areolar connective tissue
• adipose tissues
  -blood vessels
• lymphatic vessels
• nerves

Question 22

sweat glands

Answer 22

• also knows as sudoriferous glands
• two types: eccrine and apocrine
• both located in dermis or hypodermis
• found all over the body

Question 23

how does the skin work for temperature regulation in farm animals?

Answer 23

• changes in blood flow thu skin capillaries alter amount of warm blood near body surface which affects thermoregulation
• increasing amounts of blood near body surface enables animal to dissipate heat to help cool themselves

Question 24

oil glands

Answer 24

• found all over body in dermis
• releases secretion (sebum) onto hair follicles or to skin surface
• oil glands degrade epithelial cells to produce lipid based sebum

Question 25

sebum functions

Answer 25

• keep hair from becoming fragile (traps moisture to prevent excess drying
• prevents excess evaporation of moisture from skin
  -keeps skin soft
• has bacteriostatic and antifungal properties