Lab 4 Notes: The Integument

Melanocytes

________- long, branching processes; produce & store melanin, give pigment to skin and get darker with more exposure to UV light.

Keratinocytes

________- most abundant cell type; produces keratin & gives strength and waterproofing.

Friction

________ skin- refers to the skin that is present along palms, fingertips, and soles of feet; used for gripping purposes.

Merocrine

________ (eccrine) glands- package their secretions in structures called secretory vesicles and release secretion via exocytosis.

Reticular layer

________- forms the deeper portion of the dermis; consists of primarily dense irregular CT with large bundles of collagen fibers.

Sebaceous

________ (oil glands): holocrine glands that produce sebum and are most abundant on the face and scalp.

spiny layer

Stratum spinosum- (________) on top of stratum basale and underneath stratum granulosum; makes skin flexible and strong.

Hypodermis

________: (subcutaneous layer) deepest layer of the skin, stores energy and connects dermis later to muscle and bone.

Sudoriferous

________ (sweat glands): small tubular structures of the skin that produce sweat.

Tactile

________ finger pads- area of skin that is particularly sensitive (pressure, temperature, pain)

Lactiferous ducts

________- converge & form a branched system connecting the nipple to the lobules of the mammary gland.

electrical impulses

Nerves: carry ________ between brain and the rest of the body.

Keratinization zone

________: middle layer of the epidermis; can create harder, tougher cells that produce hair and horns.

Mammary

________ (lactiferous) glands- modified apocrine sweat glands that secrete milk to nourish offspring.

Lobes

________- different subcompartments of the breast.

Cornification zone

________: superficial layer of the epidermis;

Stratum

________ basale- deepest epidermal layer; ranges from cuboidal to low columnar.

Desquamation

________- peeling of the skin, unintended damage to and loss of the upper layer of skin.

Free nerve endings

________- terminal branches of dendrites.

Papillary layer

________- superficial region of dermis;

Meissners corpuscles

________- (tactile corpuscles) large, encapsulated oval receptors; determine textures and shapes with touch.

Germinative zone

________: deepest layer of the epidermis; where cells engage in mitosis & renew old cells.

Stratum corneum

________- (horny layer) most superficial layer of the epidermis; consists of 20- 30 layers of dead, interlocking keratinized cells.

small muscles

Arrector pili muscles- ________ attached to hair follicles.

clear layer

Stratum lucidum- (________) found in thick skin (hands or soles of feet); thni layer of dead skin cells.

Apocrine

________ glands- glands that accumulate their secretory products within apical portion of cytoplasm.

Dermis

________: middle layer of the skin and deep to epidermis; consists of two types of connective tissue- areolar and connective; vascular, sweat glands, sebaceous glands, and nerve endings.

Epidermis

________: top layer of the skin; epithelium of the integument, keratinized squamous epithelium, avascular & acquires nutrients from dermis.

Tactile cells

________- (Merkel cells) sensitive to touch & provide sensory info.

Breast tissue

________- composed of collagen fiber matrix and adipose tissue; lays superficial to the muscle and bone of the thorax.

epidermis

top layer of the skin; epithelium of the integument, keratinized squamous epithelium, avascular & acquires nutrients from dermis

germinative zone

deepest layer of the epidermis; where cells engage in mitosis & renew old cells

stratum basale

deepest epidermal layer; ranges from cuboidal to low columnar

keratinocytes

most abundant cell type; produces keratin & gives strength and waterproofing

melanocytes

long, branching processes; produce & store melanin, give pigment to skin and get darker with more exposure to UV light

tactile cells

(Merkel cells) sensitive to touch & provide sensory info

stratum spinosum

(spiny layer) on top of stratum basale and underneath stratum granulosum; makes skin flexible and strong

keratinization zone

middle layer of the epidermis; can create harder, tougher cells that produce hair and horns

stratum granulosum

(granular layer) lies above stratum spinosum but below stratum corneum; helps form waterproof barrier that functions to prevent fluid loss from the body

cornification zone

superficial layer of the epidermis;

stratum lucidum

(clear layer) found in thick skin (hands or soles of feet); thni layer of dead skin cells

stratum corneum

(horny layer) most superficial layer of the epidermis; consists of 20-30 layers of dead, interlocking keratinized cells

desquamation

peeling of the skin, unintended damage to and loss of the upper layer of skin

papillary layer

superficial region of dermis;

dermal papillae

projections of the dermis that interlock with epidermal ridges

reticular layer

forms the deeper portion of the dermis; consists of primarily dense irregular CT with large bundles of collagen fibers

hypodermis

(subcutaneous layer) deepest layer of the skin, stores energy and connects dermis later to muscle and bone

adipocytes

fat cells

breast tissue

composed of collagen fiber matrix and adipose tissue; lays superficial to the muscle and bone of the thorax

lobes

different subcompartments of the breast

septa

bands/highways of collagen fibers

alveoli

in breast, produces milk

lactiferous ducts

converge & form a branched system connecting the nipple to the lobules of the mammary gland

sudoriferous (sweat glands)

small tubular structures of the skin that produce sweat

merocrine (eccrine) glands

package their secretions in structures called secretory vesicles and release secretion via exocytosis

apocrine glands

glands that accumulate their secretory products within apical portion of cytoplasm

ceruminous glands

true apocrine glands, secretion mixes with both sebum and exfoliated keratinocytes for waterproofing purposes (earwax)

cerumen (earwax)

waterproof earwax

mammary (lactiferous) glands

modified apocrine sweat glands that secrete milk to nourish offspring

sebaceous (oil glands)

holocrine glands that produce sebum and are most abundant on the face and scalp

sebum

oily, waxy secretion

arrector pili muscles

small muscles attached to hair follicles

nerves

carry electrical impulses between brain and the rest of the body

free nerve endings

terminal branches of dendrites

Meissners corpuscles

(tactile corpuscles) large, encapsulated oval receptors; determine textures and shapes with touch

friction skin

refers to the skin that is present along palms, fingertips, and soles of feet; used for gripping purposes

tactile finger pads

area of skin that is particularly sensitive (pressure, temperature, pain)