Integumentary

Question 1

largest single organ of the body ; 15%-20% of total body weight

Answer 1

Skin

Question 2

two major layers of skin

Answer 2

Epidermis and Dermis

Question 3

an epithelial layer of ectodermal
origin ; the one directly observed physically

Answer 3

Epidermis

Question 4

a layer of mesodermal connective
tissue ; the thickest layer, divided into the
papillary layer and reticular layer

Answer 4

Dermis

Question 5

Structures that are embedded in the skin but
otherwise considered as a separate organ/tissue

Answer 5

Epidermal derivatives of the skin

Question 6

The four epidermal layers of the skin

Answer 6

Hair follicles and hair
Sweat (sudoriferous) glands
Sebaceous glands
Nails

Question 7

Functions of the Skin

Answer 7

Protective
Sensory
Thermoregulatory
Metabolic
Sexual signaling

Question 8

provides a physical barrier against thermal
and mechanical insults

Answer 8

Protective

Question 9

allow skin to
constantly monitor the environment

Answer 9

Sensory

Question 10

skin’s insulating components and its
mechanisms for accelerating heat loss

Answer 10

Thermoregulatory

Question 11

Cells of skin synthesize vitamin D3, needed in
calcium metabolism and proper bone
formation

Answer 11

Metabolic

Question 12

effects of sex pheromones produced by
the apocrine sweat glands

Answer 12

Sexual signaling

Question 13

consist mainly of a stratified squamous
keratinized epithelium composed of cells called keratinocytes

Answer 13

Epidermis

Question 14

Cells in Epidermis

Answer 14

Keratinocytes
Langerhan cells
Melanocytes
Merkel cells

Question 15

production of the protein
keratin ; Predominant cell type of the epidermis

Answer 15

Keratinocytes

Question 16

skin macrophage ; It possesses characteristic, tennis racquet-shaped Birbeck granules ; Most clearly seen in the spinous layer

Answer 16

Langerhan cells

Question 17

produces melanin ; Neural crest-derived ; dendritic cell that is scattered among the
basal cells of the stratum basale

Answer 17

Melanocytes

Question 18

granules that contain melanin

Answer 18

Melanosomes

Question 19

precursor of melanin

Answer 19

Tyrosine

Question 20

Epithelial tactile cells ; Function in cutaneous sensation ; Abundant in highly sensitive skin like that of fingertips and at the bases of some hair follicles ; Located in the stratum basale

Answer 20

Merkel cells

Question 21

Thick skin

Answer 21

Palms and soles

Question 22

Thin skin

Answer 22

Elsewhere on the body
─stratum basale
─stratum spinosum
─stratum granulosum
─stratum lucidum
─stratum corneum

Question 23

Layers of Epidermis

Answer 23

Basal layer (stratum basale)
Spinous layer (stratum spinosum)
Granular layer (stratum granulosum)
Stratum lucidum
Stratum corneum

Question 24

single layer of basophilic cuboidal or
columnar cells ; Characterized by intense mitotic activity and contains ; Important feature – cytoskeletal keratins

Answer 24

Basal layer (stratum basale)

Question 25

Thickest layer, especially in the epidermal ridges ; Synthesis of much keratin and other proteins takes place ; exhibit spinous processes

Answer 25

Spinous layer (stratum spinosum)

Question 26

Keratinocytes in this layer contain numerous keratohyalin granules

Answer 26

Granular layer (stratum granulosum)

Question 27

important in the aggregation of the keratin filaments ; cysteine rich and histidine rich proteins considered as the precursors of the protein filaggrin ; when released by exocytosis would usually produce a layer that is lipid rich around the cell

Answer 27

Lamellar granules

Question 28

Consists of a thin, translucent layer of flattened eosinophilic keratinocytes held together by desmosomes ; a subdivision of the stratum corneum ; Only well seen in thick skin

Answer 28

Stratum lucidum

Question 29

Most differentiated cells in the skin; Layers of squamous, keratinized cells filled with birefringent filamentous keratins ; Squames- Layers of dead skin cells

Answer 29

Stratum corneum

Question 30

layer of connective tissue that supports the epidermis and binds it to the subcutaneous tissue (hypodermis)

Answer 30

Dermis

Question 31

Layer of the Dermis

Answer 31

Papillary layer Reticular layer

Question 32

what lies between the papillary and reticular dermal layers

Answer 32

microvascular subpapillary plexus

Question 33

are the extension of the epidermis to the dermis

Answer 33

Epidermal ridges

Question 34

are projections of the dermis unto the epidermis

Answer 34

Dermal papillae

Question 35

Thin ; Topmost layer of the dermis ; Includes the dermal papillae ; Consists of loose connective tissue ; Types I and III collagen fibers, fibroblasts and scattered mast cells, macrophages, and other leukocytes

Answer 35

Papillary layer

Question 36

Much thicker ; Consists of dense irregular connective tissue ; More fibers and fewer cells than the papillary layer ; A network of elastic fibers is also present

Answer 36

Reticular layer

Question 37

Consists of loose connective tissue that binds the skin loosely to the subjacent organs, making it possible for the skin to slide over them ; Contains adipocytes ; Extensive vascular supply

Answer 37

Hypodermis or superficial fascia (Subcutaneous Tissue)

Question 38

the skin functions as an extensive receiver for various stimuli from the environment

Answer 38

Sensory Receptors

Question 39

Unencapsulated sensory receptor

Answer 39

Merkel cells Free nerve endings Root hair plexuses

Question 40

Encapsulated sensory receptor

Answer 40

Meissner corpuscles Lamellated (pacinian) corpuscles Krause end bulbs Ruffini corpuscles

Question 41

Tonic receptors for sustained light touch and for sensing an object’s texture ; Tactile disc

Answer 41

Merkel cells

Question 42

Most numerous neuronal receptors in the epidermis ; Start in stratum basale ; Terminate in the stratum granulosum ; Respond primarily to high and low temperatures, pain, and itching, but also function as tactile receptors

Answer 42

Free nerve endings

Question 43

A web of sensory fibers surrounding the bases of hair follicles in the reticular dermis that detects movements of the hairs

Answer 43

Root hair plexuses

Question 44

Elliptical structures, consisting of sensory axons winding among flattened Schwann cells arranged perpendicular to the epidermis in the dermal papillae ; Touch receptors ; Responsive to low frequency stimuli in the papillary layer of hairless skin

Answer 44

Meissner corpuscles

Question 45

large oval structures with an outer capsule and 15-50 thin ; found deep in the reticular dermis and hypodermis ; wall of the rectum and urinary bladder ; specialized for sensing coarse touch, pressure, and vibrations

Answer 45

Pacinian corpuscles

Question 46

Simpler encapsulated, ovoid structures, with extremely thin, collagenous capsules penetrated by a sensory fiber ; Found primarily in the sin of the penis and clitoris where they sense low frequency vibrations ; Also known as bulboid corpuscle/genital corpuscle ; Detects cold as a thermo receptor

Answer 46

Krause end bulbs

Question 47

Collagenous, fusiform capsules anchored firmly to the surrounding connective tissue ; Respond to stretch and torque ; Detects warm temperature

Answer 47

Ruffini corpuscles

Question 48

elongated keratinized structures that form within epidermal invaginations, the hair follicles

Answer 48

Hair

Question 49

growing hair follicle has a terminal dilation called a hair bulb

Answer 49

Hair

Question 50

base of the bulb is invaginated by a tuft of vascularized loose connective tissue called a dermal papilla

Answer 50

Hair

Question 51

these cells form the matrix of the elongating hair root ; the part of a hair extending beyond the skin surface is called the hair shaft

Answer 51

Hair

Question 52

the part of a hair extending beyond the skin surface

Answer 52

hair shaft

Question 53

A generally long period of mitotic activity and growth

Answer 53

anagen

Question 54

A brief period of arrested growth and regression of the hair bulb

Answer 54

catagen

Question 55

A final long period of inactivity

Answer 55

telogen

Question 56

hard plates of keratin on the dorsal surface of each distal phalanx

Answer 56

Nail

Question 57

The proximal part of the nail

Answer 57

nail root

Question 58

bound to a bed of epidermis, which contains only the basal and spinous epidermal layers

Answer 58

nail bed

Question 59

forms from the nail matrix in which cells divide, move distally, and become keratinized in a process somewhat similar to hair formation but without keratohyaline granules

Answer 59

nail root

Question 60

embedded in the dermis over most of the body, except in the thick, glabrous skin of the palms and soles

Answer 60

Sebaceous Glands

Question 61

branched acinar glands with several acini converging at a short duct that usually empties into Sebaceous Glandsthe upper portion of a hair follicle

Answer 61

Sebaceous Glands

Question 62

a hair follicle and its associated sebaceous glands make up a pilosebaceous unit ; holocrine secretion ; Sebocytes ; Sebum

Answer 62

Sebaceous Glands

Question 63

a complex mixture of lipids that includes wax esters, squalene, cholesterol, and triglycerides that are hydrolyzed by bacterial enzymes after secretion

Answer 63

Sebum

Question 64

helps maintain the stratum corneum and hair shafts and exerts weak antibacterial and antifungal properties

Answer 64

Sebum

Question 65

Widely distributed in the skin and are most numerous on the foot soles ; Secretory part is stratified cuboidal epithelium

Answer 65

Eccrine sweat glands

Question 66

A physiologic response to increased body temperature during physical exercise or thermal stress ; Most effective means of temperature regulation of humans

Answer 66

Sweating

Question 67

largely confined to skin of the axillary and perineal regions ; production of pheromones ; Merocrine secretion ; Simple cuboidal ; Larger lumen

Answer 67

Apocrine sweat glands

Question 68

Collagen-rich, well vascularized tissue in the dermis, which gradually replaces the blood clot ; Undergoes remodeling

Answer 68

Granulation Tissue