integument system

Question 1

what is the integument system consist of?

Answer 1

cutaneous membrane(skin) +accessory structures

Question 2

what are the functions of the system?

Answer 2

protection (forms barrier, immune response, prevents water loss), thermoregulation, sensation, storage, vitamin D synthesis, excretion

Question 3

what are the three layers of integument?

Answer 3

epidermis, dermis, hypodermis

Question 4

what are the three main cell types?

Answer 4

keratinocytes, melanocytyes, dendrtic cells

Question 5

what are keratinocytes?

Answer 5

produce keratin, 30-40 day turnover, superficial cells are dead

Question 6

what are the melanocytes?

Answer 6

produce pigment melanin, protects against UV radiation, creates tan

Question 7

what are dendritic cells?

Answer 7

immune function, macrophages patrol the skin, protect against pathogens/ cancer

Question 8

4-5 layers of the epidermis?

Answer 8

stratum corneum, stratum lucidum, stratum granulosum, stratum spinosum, stratum basale

Question 9

what is the corneum layer?

Answer 9

up to 30 layers of dead keratinocytes, cell filled with keratin, protective (cells continually shed), may contain carotene

Question 10

what is the lucidum layer?

Answer 10

few layers of thin, flat, dead keratinocytes, found only in thick skin, plantar and palmer regions

Question 11

what is the granulosum layer?

Answer 11

keritinization begins here, keratohyalin granules, glycolipid granules secrete into ECF and prevent water loss,

Question 12

what is the spinosum layer?

Answer 12

8-10 layers of tightly joined living keratinocytes, desmosomes, dendritic cells here

Question 13

what is the basale layer?

Answer 13

single layer of keritinocytes and melanocytes, access to underlying c.t and mitosis, cell growth/replacement produced here

Question 14

characteristics of the dermis layer?

Answer 14

2nd layer of skin, blood vessels/nerves here, thick layer of c.t, cells=fibroblasts and immune cells, various sensory receptors

Question 15

what two layer is the dermis consist of?

Answer 15

papillary and reticular layer

Question 16

what is the papillary layer?

Answer 16

top 20%. of dermis, tissue=loose areolar, forms papillae and epidermal ridges, detect light touch

Question 17

what is the reticular layer?

Answer 17

bottom 80% of dermis, tissue is dense irregular, thick network of collagen and elastic fibres, strength/attachement to underlying structures, lamelleted corpuscles detect pressure/ vibration

Question 18

what is the hypodermis?

Answer 18

not a layer of the skin, subcutaneous layer of integument, tissue=adipose and areolar, insulation and lipid storage, flexible

Question 19

what are the two types of exocrine glands in skin?

Answer 19

sebaceous and sweat

Question 20

what is the sebaceous gland?

Answer 20

produce sebum(oily secretion), associated with hair follicles, most active during puberty and fetal development, holocrine gland

Question 21

what are the two types of sweat glands?

Answer 21

eccrine, over body surface in palmer/planter regions, secret sensible perspiration to cool body, apocrine, hair follicles in axillary and anogenital regions, secrete fats, secreted in response to fear/ arrousal

Question 22

what is the function of hair?

Answer 22

insulation, sensation, protection

Question 23

what are the two types of hair?

Answer 23

vellus(fine body hair) terminal (course body hair)