integumentary

Question 1

what is the outermost layer of skin know as

Answer 1

skin epidermis

Question 2

name the 4 major cells found in the epidermis

Answer 2

keratinocytes, melanocytes, Merkel cells and dendritic cells

Question 3

what is the role of keratinocytes

Answer 3

produce keratin, born deep is epidermis and flatten as they move up to surface of skin, the main cell type in the epidermis

Question 4

the role of melanocytes

Answer 4

secrete melanin and found in the deepest layer of the epidermis

Question 5

the role of Merkel cells

Answer 5

specialised in sensory aids like - light touch and texture

Question 6

the role of dendritic cells

Answer 6

activate immune defence and injest invaders/ foreign materials

Question 7

name the other major layer of the skin

Answer 7

skin dermis

Question 8

what are the 2 sublayers of the dermis

Answer 8

papillary layer and the reticular layer

Question 9

name structure of the papillary layer

Answer 9

loose areolar connective tissue (elastic fibres loose and stretchy)

Question 10

name the structure of the reticular layer

Answer 10

dense irregular connective tissue (made of collagen so very tough and strong)

Question 11

name the 6 features found overall in the dermis

Answer 11

collagen, elastic fibres, blood vessels, nerve endings, sweat glands, hair follicles

Question 12

name the 4 main functions of the skin

Answer 12

protection, temperature regulation, secretion, cutaneous sensation

Question 13

name 3 things the skin must provide protection against

Answer 13

infection, physical damage(UV), chemical damage/ dehydration

Question 14

name 2 ways in which the skin monitors temp

Answer 14

hair follicles- trap layer of air to insulate and sweat glands- evaporations help cooling

Question 15

name 2 glands found in the skin that secrete

Answer 15

sebaceous gland- secreting oil and apocrine gland- secretes milky/oil producing sexual scent

Question 16

name two features in the skin allowing for cuteness sensation

Answer 16

free nerve ends- touch/pain/temp and pacinlan corpuscle- vibration and pressure

Question 17

name the 4 stages of soft tissue repair

Answer 17

1. haematoma, 2.scab formation, 3.granulation phase, 4. regeneration and remodelling

Question 18

name 3 things that occur in the haematoma phase of STR

Answer 18

1. inflammatory chemicals released, 2. local blood vessels become leaky, 3. WBC, fluid and clotting proteins seep into damaged area

Question 19

name 2 tings that occur in scab formation in STR

Answer 19

1. clot seals injured area from infection, 2. clot dries and forms scab

Question 20

name 4 things that occur in granulation phase in STR

Answer 20

1. ingrowth of fragile capillaries replace scab, 2. fibroblasts multiply and produce collagen fibres and growth factors, 3. macrophages phagocytise dead cells and debris, 4. surface epithelial begins to multiply over granulation tissue

Question 21

name 3 things that occur in regeneration and remodelling phase of STR

Answer 21

1. fibroses area contracts pulling wound together, 2. epithelium thickens under scab that then detaches, 3. fully generated epidermis with scar-tissue underneath.

Question 22

name the 4 stages of bone repair

Answer 22

haematoma, soft callus, hard callus and remodelling

Question 23

name e the 2 things that happen in haematoma phase of BR

Answer 23

blood vellsel in bone and periosteum are torn, 2. bone cells become starved and die, causing cell death and swelling and haematoma forms

Question 24

name the 3 stages in soft callus formation in BR

Answer 24

1.fibroblasts and chondroblasts invade site, 2. fibroblasts produce collagen connecting ends of bone, 3. chondroblasts produce cartilaginous matrix that then calcifies forming soft callus (fibro-cartillaginous callus)

Question 25

name the 3 stages in soft callus formation in BR

Answer 25

1.fibroblasts and chondroblasts invade site, 2. fibroblasts produce collagen connecting ends of bone, 3. chondroblasts produce cartilaginous matrix that then calcifies forming soft callus (fibro-cartillaginous callus)

Question 26

name the 3 stages in hard callus formation in BR

Answer 26

1.osteoblasts begin to form spongey bone, 2. trabeculae spans the callus and unites the two beaks, 3. soft callus slowly replaced by mature bone, converting to hard callus

Question 27

name the 3 stages in remodelling in BR

Answer 27

remodelling begins during hard callus stage, 2. excess material removed from diaphysis exterior and medullary cavity, 3. compact bone layer down to reconstruct shaft walls.

Question 28

what is colouration of the skin caused by

Answer 28

haemoglobin, melanin, carotene

Question 29

name 3 abnormal colourations of the skin

Answer 29

cyanosis, jaundice, albinism, haematoma, pallor