Integumentary

Question 1

What are the functions of the skin?

Answer 1

Protection, Excretion, Assistance in thermoregulation, Synthesis of Vitamin D and Sensory Perception

Question 2

What does the 6 factors the skin protects against?

Answer 2

Mechanical damage, Chemical damage, Bacterial damage, Ultraviolet radiation, Thermal damage and Disiccation (drying out).

Question 3

How does the skin protect against mechanical damage?

Answer 3

Forms a physical barrier and contains pressure receptors alerting nervous system of possible damage

Question 4

How does the skin protect against chemical damage?

Answer 4

Is relatively impermeable keratinised cells and has pain receptors alerting NS of damage

Question 5

How does the skin protect against bacterial damage?

Answer 5

Has unbroken surface and acid mantle. Skin secretions are acidic which inhibit bacteria. Phagocytes ingest so they dont penetrate deeper

Question 6

How does the skin protect against UV radiation?

Answer 6

Melanin is produced by melancytes and is a protective barrier

Question 7

How does the skin protect against thermal damage?

Answer 7

Contains hot, cold and pain receptors to alert NS

Question 8

How does the skin protect against desiccation?

Answer 8

Contains waterproof keratin.

Question 9

What is the skin function in excretion?

Answer 9

Gets rid of water, salts and inorganic wastes (urea/uric acid)

Question 10

What is the skin function in thermoregulation?

Answer 10

Uses sweating mechanism to regulate body temperature

Question 11

What is the skin function in synthesis of vitamin D?

Answer 11

Modified cholesterol molecules in skin are converted to Vitamin D when skin exposed to UV

Question 12

What are the sensory perception of skin?

Answer 12

Touch, Pain, Pressure and Temperature

Question 13

What are the layers of the skin?

Answer 13

Epidermis, Dermis and Sub-cutaneous layer.

Question 14

What type of tissue does the Epidermis have?

Answer 14

Stratified squamous epithelial and can be keratinising (hard and tough)

Question 15

What type of tissue does the dermis have?

Answer 15

Dense connective tissue

Question 16

What is the connection between Epidermis and Dermis?

Answer 16

They are tightly connected but burn or friction may cause separation (blister).

Question 17

What is the role of the hypodermis?

Answer 17

Anchors skin to underlying organs also acts as a shock absorber and insulates deeper tissue from extreme temperature change. Gives curved surfaces

Question 18

How many layers dies the Epidermis and Dermis have?

Answer 18

The epidermis has 5 layers which are superficial (may be 4). Dermis has 2 layers and is deepest

Question 19

What are the characteristics of the epidermis?

Answer 19

Avasular (no blood supply of own), contains keratinocytes, produces keratin (fibrous protein making tough protective layer)

Question 20

List the layers of epidermis from deepest to most superficial.

Answer 20

Stratum Basale (Germinatiuum), Stratum Spinosum, Stratum Granulosum, Stratum Lucidum and Stratum Corneum

Question 21

What are the characteristics of keratinocytes?

Answer 21

tough fibrous water repellent protein, provides durable overcoat for body, protects deeper cells from water loss, helps against bio, chem and physical assaults.

Question 22

How often are the cells of the epidermis replaced?

Answer 22

Every 35-45 days

Question 23

What are melanocytes?

Answer 23

Produces brown pigment which is stimulated by sunlight-tanning.

Question 24

What are the characteristics of melanocytes?

Answer 24

Found in Stratum Basale and is a phagocytose pigment. Forms protective pigment over nucleus and shields DNA from UV damage.

Question 25

How is skin cancer formed?

Answer 25

excessive sun exposure alters DNA of skin cells.

Question 26

What are the characteristics of the dermis?

Answer 26

Rich in nerve fibres, blood vessels, sebaceous glands and sweat glands. They shield and repair injured tissue and are the strong stretchy envelope holding the body together.

Question 27

What are the 2 major regions of the dermis?

Answer 27

Papillary (superficial layer) and Reticular (deeper layer)

Question 28

What does the Dermis contain?

Answer 28

Nerve endings, sweat glands and hair follicles

Question 29

What supplies the dermis?

Answer 29

Blood vessels which dilate or constrict depending on body temperature.

Question 30

What does the papillary layer contain?

Answer 30

loose connective tissue, capillaries and sensory nuerons

Question 31

What does the dermal papillae contain?

Answer 31

Capillary loops that furnish nutrients to epidermis

Question 32

What are the Meissners Corpuscles?

Answer 32

House pain receptors (free nerve endings) and touch receptors

Question 33

What does the reticular(deepest) layer contain?

Answer 33

Blood vessels, sweat and oil glands, deep pressure receptors (pacinian corpuscles) and phagocytes

Question 34

What are the characteristics of the Dermis?

Answer 34

irregular arrangement of collagen (strength) and elastic (flexibility) fibres, many blood vessels.

Question 35

What are the 3 pigments that contribute to skin colour?

Answer 35

kind melanin(yellow, red, brown, black) in epidermis, carotene (orange/yellow) in stratum corneum and o2 bound to haemoglobin in dermal blood vessels

Question 36

What are the accessories for skin?

Answer 36

Hair, arrector pili muscles, subaceous glands, sweat glands, nerve endings and nails

Question 37

What is the function of hair on skin?

Answer 37

To protect

Question 38

How is hair produced and what are the parts?

Answer 38

Produced by hair follicle and formed by division of stratum basale epithelial cells in growth zone (hair bulb matrix) and is flexible epithelial structure. Part enclosed by follicle is root and projecting from skin is shaft.

Question 39

What is the living and dead part of the hair?

Answer 39

The bulb (end ) is only living and cells divide rapidly. Bulb lies in dermis/subcutaneous tissue and dead part forms a hard keratin.

Question 40

What is the Arrector Pili Muscle?

Answer 40

small muscle that contracts to make hair stand on end

Question 41

What is the sebaceous glands?

Answer 41

Ducts that usually empty into hair follicle which provides oily substance (sebum) keeping hair and skin lubricated. Can also kill bacteria

Question 42

What are the types of sweat glands called?

Answer 42

Eccrine (most numerous) and Apocrine (sticky secretions)

Question 43

What are the characteristics of the eccrine sweat gland?

Answer 43

Most common, thin and watery secretion with smaller coiled glands, assists in cooling and protection and controlled by ANS

Question 44

What are the characteristics of the apocrine sweat gland?

Answer 44

Located in axilla, ground and around nipples, coiled glands that communicate with hair follicles, produce sticky cloudy secretions, controlled by ANS and hormones.

Question 45

What sweat does the Eccrine sweat glands produce?

Answer 45

Clear, primarily water, some salt, vitamin c, lactic acid and traces of metabolic waste.

Question 46

What sweat does the apocrine sweat glands produce?

Answer 46

All from eccrine, fatty acids, proteins, may have odour.

Question 47

What are the characteristics of the nails?

Answer 47

From dermal layer, dead tightly compressed cells with keratin, for protection and can be influenced by illness

Question 48

What are the characteristics of the subcutaneous layer?

Answer 48

Loose connective tissue with adipose tissue, connects skin to tissues and organs