Bio anatomy and physiology Chapter 5: Integumentary System

Stratum corneum

- As cells are pushed toward the surface of the skin, they become flat and hard, forming the tough, uppermost layer of the epidermis. - Hardening is caused by keratinization

Psoriasis

- Disorder of the immune system that causes immune cells to target the epidermis - cells reproduce more rapidly than normal

Stratum Spinosum

- Immediately superior to the stratum basale - Can reproduce by mitosis - Spiny appearance created by keratin filaments

Stratum Granulosum

- Immediately superior to the stratum basale - cells are flattened and tightly sealed together and form a barrier. - cells contain more keratin than stratum spinosum

Free nerve endings

- Sensory nerve that supply pain and temperature sensations to the brain

Stratum Lucidum

- This layer creates calluses. - just deep to the stratum corneum - This layer is only found in thick skin: palms of the hands, soles of the feet, elbows, etc.

Dermis

- This layer, a deeper and thicker region than the epidermis, is composed of dense irregular connective tissue - upper layer has fingerlike projections called dermal papillae - Contains collagen and elastic fibers

Melanocytes

-Another type of specialized cell located in the deeper epidermis. - Produce melanin, the pigment primarily responsible for skin and hair color

Hypodermis

-Composed of loose connective tissue, including adipose (fat) tissue. - lies below the dermis - Fat is an energy storage form that can be called upon when necessary to supply the body with molecules for cellular respiration

Epidermis

-The outer and thinner region of the skin. - Made up of stratified squamous epithelium divided into five separate layers, or strata. - From deepest to most superficial: Stratum basale, stratum spinosum, stratum granulosum, stratum lucidum, and stratum corneum. - Lacks blood vessels and has tightly packed cells

C. the hypodermis and the dermis

Blood vessels can be found in: A. the epidermis, dermis, and hypodermis B. the dermis only C. the hypodermis and the dermis

Stratum Basale

Epidermal stem cells constantly divide and produce new cells that are pushed to the surface of the epidermis.

- Hair Matrix - hair matrix cells continually divide, producing new keratinocytes that form a hair.

Hair follicle cells are found in a structure called the hair ______, located at the base of the hair.

- Sweat contains salts and urea, which are also excreted by the kidneys.

How does the skin help the urinary system eliminate wastes from the body?

Skin protects muscle; rids the body of or conserves heat produced by muscle contraction. Muscle contraction provides heat to warm the skin

How does the skin work with the muscular system?

Skin protects bones; helps provide vitamin D for Ca^2 absorption. Bones provide support for skin

How does the skin work with the skeletal system?

First degree burn

In ____ degree burns, only the epidermis is affected.

Keratinocytes

The most numerous cells in the stratum basale, compromising approximately 95% of the cells in this layer. - Produce and store a thick waterproof protein called keratin. (protect the body from outside environment)

Melanoma

The type of cancer that is more likely to be malignant, starts in the melanocytes and looks like an unusual mole.

Tactile cells (Merkel cells)

These cells signal the brain when an object has touched the skin

Sebaceous Glands

These glands secrete an oily substance called sebum that flows into the follicle and then out onto the skin surface.

Ultraviolet light

What causes all forms of skin cancer?

Fibroblasts

What cell type is responsible for scar formation?

The deepest layer is the stratum basale, and the most superficial layer is the stratum corneum.

What is the deepest layer of the epidermis? what is the most superficial layer?

Basal cell carcinoma - About 95% of patients are easily cured

What is the most common type of skin cancer?

- Constrict. the process keeps blood in the body's torso, retaining heat in the body

When body temperature drops below normal, blood vessels in the dermis _________. Explain how this prevents body temperature from dropping further

formed from epidermal cells but are located in the dermis of the skin

Where are the hair follicles located?

B. Langerhans cells

Which of the following white blood cells found in the epidermis phagocytize microbes and stimulate the immune system? A. Merkel cells B. Langerhans cells C. Melanocytes

A. Hair matrix

Which part of the hair contains actively growing cells? A. hair matrix B. Hair shaft C. Hair root

Second degree burn

_____ degree burns extend through the entire epidermis and part of the dermis.

Third degree burn

_____ degree burns, or full-thickness burns, destroy the entire thickness of the skin.

Mammary Glands

______ glands are modified apocrine sweat glands that produce milk only after childbirth.

- Apocrine glands - secrete through exocytosis

______ glands open into hair follicles in the anal region, groin, and armpits.

Langerhans cells

________ cells are macrophages found deep in the epidermis. - Macrophages are a type of white blood cell (leukocyte.) - Stimulate the immune system to react

Hyperthermia Hypothermia

___________, a body temperature above normal, and __________, a body temperature below normal.