integumentary system

Question 1

layers of the epidermis from outer to innermost:

Answer 1

COME LETS GET SOME BEERS
1. stratum corneum - outermost hydrophobic layer
2. stratum lucidium - only present in palms of hands and soles of feet
3. stratum granulosum - skin cells lose organelles here, begin dying, and are filled with keratin
4. stratun spinosum - provides skin strength/flexibility; held together by desmosomes
5. stratum basale (germinativium) - deepest layer of epidermis where new skin cells are formed

Question 2

dermis

Answer 2

second layer of skin and highly vascularized. it is connected to the epidermis above via the basement membrane

Question 3

epidermal cells

Answer 3

• melanocytes
• merkel cells
• keratinocytes
• langerhans cells

Question 4

melanocytes

Answer 4

transfers skin pigment melanin to keratinocytes

Question 5

merkel cells

Answer 5

attach to sensory neurons and functions in touch sensation

Question 6

keratinocytes

Answer 6

produce keratin
help waterproof

Question 7

langerhans cells

Answer 7

interact with immune cells

Question 8

papillary region

Answer 8

• vascular network within upward projecting papillae that helps supply nutrients to epidermis and regulates temperature
• papillae contain Meisner’s corpuscles (sensory touch receptors)

Question 9

hypodermis (subcutaneous)

Answer 9

• consists of areolar and adipose tissue
• functions in fat storage, heat insulation, and shock absorption
• contains pressure sensing nerve ending and passage for blood vessels

Question 10

reticular region

Answer 10

region with dense connective tissue, collagen, and elastic fibers; packed with glands, sweat gland ducts, fat, and hair follicles

Question 11

order of skin

Answer 11

• epidermis
• dermis
• papillary dermis
• reticular dermis
• hypodermis

Question 12

thermoregulation in skin

Answer 12

• aids in regulating body temperature
• capillaries dilate to release heat, and constrict to preserve heat
• goosebumps (piloerection reflex) occurs when cold, elevates hairs to trap heat

Question 13

environmental sensory input

Answer 13

nerve endings in skin convey temp, pressure, pain, and touch

Question 14

vitamin D synthesis

Answer 14

UV radiation activates skin molecules to synthesize vitamin D

Question 15

eccrine glands

Answer 15

• opens directly to skin, located on majority of skin
• regulates temperature through perspiration and urea elimination

Question 16

apocrine glands

Answer 16

• opens to hair follicles; more viscous secretions
• located: armpits, pubic region, nipple

Question 17

hair

Answer 17

• keratinized cells
• unique to the skin of mammals

Question 18

sebaceous (oil) glands

Answer 18

• connected to hair follicles
• secrete oil (sebum) that discourage microbial growth

Question 19

ceruminous (wax) glands

Answer 19

found in ear canal and produce a wax-like material that acts as a barrier to entrance

Question 20

mammary (milk) glands

Answer 20

secretes milk