Integumentary System Flashcards
Define the meaning of:
Integumentary
cutaneous
covering
skin
List the components of the integumentary system
Cutaneous membrane - epidermis, dermis, accessory structures
Subcutaneous layer
List the functions of the integument
Protection / waterproofing Temperature maintenance Sensory reception Synthesis and storage of nutrients Excretion + secretion Synthesises Vit D with UV
State the number of layers in thick + thin skin
5 layers of thick skin e.g. palms and soles
4 layers of thin skin e.g. back of hand
Name the 5 cell layers of the epidermis
Stratum germinativum Stratum spinosum Stratum granulosum Stratum lucidum Stratum corneum
What 3 types of cells does the Stratum germinativum (basal layer) contain?
Merkel cells
Stem cells
Melanocyte - synthesise melanin
List some features of the Stratum spinosum
8-10 layers of cells that look like pin cushions
containg langerhan cells
may contain superficial cancer cells
List some features of the Stratum granulosum
3-5 layrs
keratin granules in the cytoplasm
no cell division
List some features of the Stratum lucidum
found in thick skin
flattened, densely packed and filled with keratin
List some features of the Stratum corneum
15-30 layers of flattened, dead cells
abundant keratin
Stratum basal cells take __ - __ days to reach stratum corneum.
Cells remain in stratum corneum for an additional __ weeks before they shed.
15-30
2
Define insensible perspiration
Water loss through the stratum corneum to the surface and then evaporates
What glands produce sensible perspiration?
sweat glands
Give two ways in which the epidermis can be damaged to speed up water loss
blisters
burns
What are the 3 sources of skin colour?
Melanocytes
Carotene
Hemoglobin
Melanocytes make pigment called _____, which provides __ protection. It gives a _______ to ______ colour
melanin
UV
red/brown to brown/black
Carotene is a pro vitamin provided from our ____, that gives a ________ colour.
diet
orange/yellow
Hemoglobin carries __ to tissues and ___ away from tissues, and gives a _____ pigment.
O2
CO2
blood red
In the presence of UV radiation, _______ migrate to the superficial surface of the nucleus to protect the ___ from harmful radiation.
melanosomes
DNA
Give 1 beneficial effect of UV radiation and 4 harmful effects.
+ Activates synthesis of vit D
- sun burn
- premature ageing, wrinkles
- malignant melanoma
- basal cell carcinoma
Name the 4 cell types in the dermis
fibroblasts
macrophages
mast cells
WBCs
Name the 3 fiber types in the dermis
collagen
elastic
reticular
What roles does the dermis have?
Temp. regulation
strong, flexible connective tissue
Rich supply of nerves and vessels
Name the 2 layers of the dermis
Papillary - top layer
Reticular - 80% of dermis
- bottom layer
The papillary layer consists of ______ CT with collagen and _____ fibres.
Dermal _____ form ridges that form our fingerprints, palms and footprints
areolar
elastic
papillae
The reticular layer consists of dense, _____ CT and is a network of _____ fibres.
The reticulum _____ the epidermis and provides _____ nerves .
irregular
collagen
supports
sensory
Describe how stretch marks form
Excessive stretching of the dermis
Patterns of collagen and elastic fibres form lines of cleavage
How are lines of cleavage formed
Caused by the orientation of parallel bundles of collagen and elastic fibres.
The lines form by following lines of tension. Bundles are aligned to resist tension
If you cut the body’s lines of cleavage at right angles, the cut will remain ____ because the elastic fibres will ____.
open
recoil
What is the cutaneous plexus?
network of vessel connecting hypodermis to the dermis
What is the papillary plexus?
network of vessels between the epidermal ridge and dermal papillary layer
The subcutaneous layer is also known as the _____
hypodermis
What is the function of the hypodermis?
To stabilise the skin’s position, loosely attached to dermis above and muscle below.
What are the 2 roles of fat cells in the hypodermis?
Provide thermal insulation
cushion muscle tissue
The hypodermis safely receives _______ needles.
hypodermic
Name the 3 skin accessories
Hair
Glands
Nails
List the 4 functions of hair
Warmth
Protection
Prevent foreign particles entering (nasal/ears/lashes)
Sense touch
Hair is made of _____, and consists of 3 concentric layers ; ______ , ______ , and _____
keratin
medulla - core
cortex - surrounds medulla
cuticle
The _____ ___ muscles are what produce goose bumps.
arrector pilli
Describe and name the 2 hair types
Vellus - fine, short hair
Terminal - pigmented, long, course hair
Hair colour is _____ determined but it is influenced by ______ and ______
genetically
hormones
environment
Name 3 glands of the skin system
Merocrine
Aprocine
Sebaceous
What 2 glands are known as sweat glands?
merocrine
apocrine
Sebaceous glands produce an oily secretion known as _____ .
sebum
Where are Sebaceous glands found?
face, back, chest, nipples, male sex organs
What makes up sebum?
triglycerides
cholesterol
proteins
electrolytes
Sebum limits the growth of ______
bacteria
If sebaceous glands get blocked a _______ is formed
furuncle/boil
Give 2 functions of sebum
Keeps skin moist
gives hair a sheen
What do abnormally active sebaceous glands in adults cause?
they inflame and epidermal cells scale off - dandruff
Where are merocrine glands found?
palms
soles
forehead
Where are apocrine glands found?
groin
anal
beard
What is the sweat made of of that is produced by merocrine glands?
99% water
salt
urea
pH 4.8-6.8
What is the sweat made of of that is produced by apocrine glands?
fatty acids - thicker, milkier sweat
Merocrine glands produce ______ perspiration for cooling the body
watery
The strong odour of sweat produced by apocrine glands is due to ______ decay
bacterial
What stimulates scent glands?
sex and stress
What are the fibers in fingerprints, footprints and palms?
Collagen - strength
Elastic - stretch-recoil
Tension lines - direction the bundles of fibers are arranged
What is the function of epidermal ridges on surface of fingerprints?
enhance grip
Name the 4 stages of skin healing
Inflammation - blood flow increased and phagocytes attracted
Scab formation
Cell division + migration
Scar formation
What are fibroblasts?
connective tissue cells that secrete fibers
What is a nociceptor?
A sensory neuron that responds to potential tissue damage
Pain fibres transmit impulses to the _____ ____ via fast/ slow fibres.
spinal cord
Describe the difference between the 2 types of pain fibers.
A-delta fibers - small myelinated fibers that transmit FAST, sharp pain
C-fiber - small unmyelinated fibers that transmit SLOW, dull pain
What do melanocytes synthesise?
melanin to produce a brown pigment
