Integumentary System and Sensory Receptors Vocabulary

Vocabulary flashcards covering key terms, layers, structures, glands, receptors, and pathology of the integumentary system based on lecture notes.

what’s the epidermis and 5 layers

The outer layer of the skin

stratum corneum, stratum lucidum, stratum granulosum, stratum spinosum, and stratum basale

what is the stratum corneum

many layers of dead cells, filled with keratin, and protects you from outside environment

what is the stratum lucidum

clear layer in only thick skin (palms/soles); dead cells

what is the stratum granulosum

layer with cells that contain keratin granules and waterproofs + produces keratin

what is the stratum spinosum

cells connected by desmosomes, spiky, and strengthens

what is the stratum basale

one layer of cells attached to basement membrane and where it makes new cells + melanin with melanocytes

what is the dermis

The layer in between the epidermis and subcutaneous layer that anchors epidermal accessory structures

has two components: outer papillary and deep reticular layer

what is the papillary layer

The outer layer of the dermis containing smaller capillaries, lymphatics, and sensory neurons. they also nourish the epidermis and increase surface area through dermal papillae.

what is the reticular layer

The deep layer of the dermis that contains a network of blood vessels, collagen and elastic fibers.

what are collagen fibers

dermal fibers that are very strong and resist stretching but bend easily, providing flexibility to skin tissue.

what are elastic fibers

dermal fibers that permit stretching and recoil to original length, limiting flexibility of collagen fibers to prevent damage.

what is the cutaneous plexus

network of arteries along the reticular layer of the dermis.

what is the papillary plexus

capillary network in the papillary layer of the dermis.

what is the venous plexus

capillary return network deep to the papillary plexus in the dermis.

what is the hypodermis

the subcutaneous layer made of elastic aerolar and adipose tissue underneath the epidermis and dermis. contains few capillaries (no organs) and site for subcutaneous injections

what is the hair follicle

structure thats ,deep in the dermis, wrapped in a dense connective tissue sheath and produces nonliving hair.

what is the arrector pili

Involuntary smooth muscle attached to hair follicle and causes hairs to stand up and produces goose bumps.

what are sebaceous glands

exocrine glands that lubricate hair and control bacterial growth on the skin.

where is the medulla of hair

central core of the hair shaft and contains soft flexible keratin.

where is the cortex of hair

middle layer of hair shaft and contains thick layers of hard keratin (provides hair stiffness)

where is the cuticle of the hair

The thin surface layer of the hair shaft containing tough, hard keratin.

what is the glassy membrane

dense connective tissue sheath surrounding the hair follicle and contacts the connective tissues of the dermis.

apocrine sweat glands

glands found in armpits, nipples, and groin that secrete sticky, cloudy secretions into hair follicles and produce odor upon bacterial breakdown. also surrounded by myoepithelial cells

myoepithelial cells

Cells surrounding apocrine sweat glands and squeeze secretions onto the skin surface in response to hormonal or nervous signals.

merocrine (eccrine) sweat glands

coiled tubular glands widely distributed over the body (especially palms and soles) that discharge sensible perspiration directly onto the skin surface.

insensible perspiration

sweat glands producing unnoticeable sweat under normal, resting body temp (500ml/day)

sensible perspiration

designed to cool the body when hot, dilating dermal vessels to increase sweat gland activity (noticeable sweat) (12 L)

what is sensation

arriving sensory info. caused by local depolarization of a receptor cell reaching action potential threshold.

what is perception

conscious awareness and interpretation of a sensation arriving at a cortical neuron.

receptive field and what does a larger field mean

area monitored by a single receptor cell

larger field = stimulus localization more difficult.

exteroceptors

sensory receptors that provide info. on external environment.

proprioceptors

mechanoreceptors that report positions of skeletal muscles and joints and what you choose to move

strictly within the somatic system (voluntary movement + conscious sensory info)

interoceptors

sensory receptors that monitor visceral organs + internal body functions.

nociceptors

general sensory receptors specialized for detecting pain.

thermoreceptors

general sensory receptors specialized for detecting temperature changes.

mechanoreceptors

general sensory receptors specialized for detecting physical distortion (touch, pressure, vibration, stretch)

chemoreceptors

general sensory receptors specialized for detecting chemical concentrations (how much fluid)

tactile receptors

type of mechanoreceptors providing sensations of touch (shape/texture), pressure (mechanical distortion), and vibration (pulsing/oscillating pressure)

free nerve endings

Tactile receptors between epidermal cells, sensitive to touch and pressure, small receptive fields.

root hair plexus

nerve endings that monitor distortions/movements across the body surface (wherever hair is located)

tactile discs (Merkel discs)

fine touch and pressure tactile receptors, in the stratum basale layer, very small receptive fields.

tactile corpuscles (Meissner’s corpuscles)

fine touch, pressure, and low-frequency vibration receptors, in dermal papillae, (most abundant in eyelids, lips, fingertips, nipples, genitalia)

lamellated corpuscles (Pacinian corpuscles)

tactile receptors, sensitive to deep pressure + distortion of skin, in reticular layer of the dermis.

ruffini corpuscles

Tactile receptors, sensitive to pressure and skin distortion, in reticular layer of dermis.

gangrene

dead (or dying) body tissue when local blood supply to tissue is lost or inadequate to keep the tissue alive.

what do nerve fibers in the skin control?

blood flow and gland secretions

function of the hair

protects, insulates, guards openings against particles+insects, and sensory info

layers in the hair follicle

internal root sheath, external root sheath, and glassy membrane

what is the autonomic nervous system

controls apocrine and merocrine glands to cause either vasodilation or vasoconstriction

also regulates internal organs and muscles

what is thermoregulation

main function of sensible perspiration, to regulate body temp, and works w/ cardiovascular system

general senses include:

temperature, pain, touch, pressure, vibration, and proprioception

special senses include:

olfaction, vision, gustation, equilibrium, and hearing

smell, taste, balance

receptor specificity meaning

each receptor has a characteristic sensitivity

four (4) general sensory receptors

nociceptors, mechanoreceptors, thermoreceptors, chemoreceptors

fine touch + pressure tactile receptors

extremely sensitive, narrow receptor field, detail info.

such as exact location, shape, size, texture

crude touch + pressure tactile receptors

poor localization, large receptor field, little info about the stimulus

six (6) tactile receptors in the skin

free nerve endings, root hair plexus, tactile discs, tactile corpuscles, lamellated corpuscles, ruffini corpuscles