Integumentary system: A&P Exam 2

(Shobnom, Auburn University)

The outer covering & largest organ of body is

Integument

Skin & accessory organs (hair, skin, nails, glands, etc) make up the

Integument

The 2 distinct regions of the integument are

Epidermis, dermis

The fatty connective tissue layer that lies below the dermis & epidermis is called the ____ or ______ layer

Hypodermis, subcutaneous

The ingegument makes up ___% of body weight and covers ___ square meters

16%, 2

The deeper layer of skin is well vascularized with ____ ____and ____ _____ that communicate with the brain

Blood vessels, nerve fibers

The 2 regions within the dermis are the

papillary layer, reticular layer

The epidermis has no blood vessels or is

Avascular

The epidermis is make of _____ ____ _____ _____

Keratinized, stratified squamous epithelium

There are ___ to ____ layers of epithelial cells in the epidermis

4-5

Most cells in the epidermis create____ for protection

keratin

Thick skin is on the palms of the hands and soles of the feet, & has a thicker ____ than thin skin

epidermis

Unlike thin skin, thick skin has no ____ ____ or _____ glands

hair follicles, sebaceous

Thick skin has an “extra” layer called the ___ ____ between the stratum corneum & stratum granulosum

stratum lucidum

The epidermis is mostly made up of keratinocytes besides the ____ _____, the deepest layer

stratum basale

The (5) functions of the skin include:

Protection, Sensation, Thermoregulation. Vitamin D Synthesis, Nonverbal communication (acne, scar, birthmark)

Dead cells lie at the surface of the epidermis and are packed with tough protein called

Keratin

Since the epidermis has no blood vessels, it depends on underlying connective tissue to diffuse

Nutrients

Living karatinoctyes in the epidermis act as

a protective barrier

Macrophages originating in bone marrow, found in stratum spinosum & granulosum

Dendritic cells

specialized cells in the deepest layer (Basal) of the epidermis that act as touch receptors

tactile cells (Merkel Cells)

Cells Responsible for giving skin its color, only in stratum basal

Melanocytes

Cells in the stratum basale that give rise to keratinoctyes

Stem Cells

The 5 epidermal strata layers from top to bottom are (above the dermis):

Stratum corneum, stratum lucidium, stratum granulosum, stratum spinosum, stratum basale

Epidermal layer with a single layer of cuboidal to low columnar stem cells (deep)

Stratum Basale

Epidermal layer with numerous desmosomes & cell shrinkage

Stratum Spinosum

Epidermal layer with 3-5 layers of flattened keratinocytes

Stratum Granulosum

Epidermal layer only in thick skin, thin and translucent

Stratum lucidum

Horny layer of epidermis, up to 30 layers of dead skin/keratinocytes

stratum corneum

In thick skin, the epidermis is around ___ thick

0.5 mm

In thin skin, the epidermis is around ___ thick

0.1mm

Thin skin has ___ follicles, ____ glands, and ____ glands

hair, sebaceous, sweat

The Dermis is composed mainly of ___ with elastic fibers, reticular fibers, and fibroblasts

collagen

What major layer of skin has lots of blood vessels, sweat glands, sebaceous glands, and nerve endings?

The dermis

The dermis is about ___ to ___thick depending on the area of the body

0.2 mm to 4mm

What layer of the dermis is superficial and is areolar tissue

The papillary layer

what layer of the dermis is thick and composed of dense irregular connective tissue (stretch marks)

reticular layer

what muscles are responsible for goose bumps & hair follicles

Piloerector muscles

What are the upward fingerlike extensions of the dermis called?

Dermal Papillae

The deepest layer of the skin that is composed of areolar & adipose tissue is the

Hypodermis

The hypodermis binds skin to underlying tissues and is thicker in

women

Drugs injected into the body hit the ____ which is highly vascular & absorbs them quickly

Hypodermis

The 3 skin pigments are

1. melanin (eumelanin, pheomelanin) 2. Carotene (yellow) 3. Hemoglobin (pink)

Allows manipulation of small objects & is unique to everyone

Friction Ridges

Marks sites where skin folds during flexion of the joints

flexions lines

Birth marks are called

hemangiomas

The type of hair that is fine, downy, & unpigmented (fetal)

Lanugo

Fine, pale hair that replaces lanugo by time of birth

vellus

longer, courser hair that is heavily pigmented (eyebrows, lashes)

Terminal

The 3 parts of a hair is

bulb, root, shaft

the 3 stages of the hair cycle are

Agagen (growth, 90% of scalp at a given time)

Catagen (degenerative stage)

Telogen (resting stage)

Fingernails & toenails are mostly made of ___ ____ cells and are packed with hard keratin

Stratum Corneum

The 2 types of sweat glands are

merocrine (thermoregulation) & apocrine (pheromones)

The type of gland that keeps skin & hair from becoming dry & brittle, and cracked

Sebaceous glands (sebum)

Type of glands found only in external ear canal

Ceruminous

Glands found in breasts of women, modified apocrine sweat gland

Mammary glands

Tissue repair in which damaged or dead cells are replaced with the same cell type

Regeneration

Type of repair in which the gap is filled with scar tissue & functional activities are not restored

Fibrosis

Burns only in epidermis

First degree Burns

burns involved in Epidermis & part of dermis

Second degree burns

Burns that involve the dermis, epidermis, and hypodermis layer

3rd degree burns

The type of skin cancer in melanoctyes and most dangerous is

Melanoma

Second most common type of skin cancer

Squamous Cell carcinoma

the most common type of skin cancer, arising from basal cells in the epidermis

Basal cell carcinoma