MAP Unit 4: Histology and Integument Continued

What are glands?

Structures made of one or more specialized epithelial cells that produce and release substances.

What are exocrine glands?

Glands that release their products through ducts onto an epithelial surface or lining.

What are examples of exocrine glands?

Sweat glands, salivary glands, lacrimal glands, and goblet cells.

What do goblet cells produce?

Mucus.

What do lacrimal glands produce?

Tears.

What are endocrine glands?

Ductless glands that release hormones into the surrounding fluid and blood.

What are hormones?

Chemicals that regulate body activities such as growth and development.

What are examples of endocrine glands?

Pituitary, thyroid, and adrenal glands.

What is the main difference between exocrine and endocrine glands?

Exocrine glands use ducts; endocrine glands are ductless and release hormones into the blood.

What are mucous membranes?

Membranes that line body passages and cavities that open to the outside.

Where are mucous membranes found?

Digestive, respiratory, urinary, and reproductive tracts.

What do mucous membranes secrete?

Mucus.

What are the functions of mucus?

Prevents drying, traps particles, and lubricates passageways.

What are serous membranes?

Membranes that line closed body cavities and cover organs within them.

What are the two layers of a serous membrane?

Parietal and visceral layers.

What is the parietal layer?

The layer attached to the cavity wall.

What is the visceral layer?

The layer attached directly to an organ.

What is serous fluid?

Watery fluid that reduces friction between organs.

What is the pleura?

The serous membrane covering the lungs.

What is the pericardium?

The serous membrane surrounding the heart.

What is the peritoneum?

The serous membrane lining the abdominal cavity and covering abdominal organs.

What are synovial membranes?

Membranes that line the cavities of freely movable joints.

What do synovial membranes produce?

Synovial fluid.

What is the function of synovial fluid?

Lubricates joints and nourishes articular cartilage.

What are cutaneous membranes?

The skin, which covers the outside of the body.

What is the main function of the cutaneous membrane?

Protects the body from injury, microorganisms, UV radiation, and water loss.

What is the integumentary system?

The skin and its associated structures, including hair, nails, glands, and nerve endings.

Why is the integumentary system considered an organ system?

Its tissues work together to perform specific functions.

What is the largest organ in the body?

The skin.

What structures are included in the integumentary system?

Skin, hair, nails, glands, and nerve endings.

What are the main functions of the skin?

Temperature regulation, protection, sensation, excretion, immunity, and vitamin D synthesis.

How does the skin regulate body temperature?

Sweat evaporates from the skin and cools the body.

How does the skin protect the body?

Acts as a barrier against injury, bacteria, dehydration, and UV radiation.

How does the skin detect stimuli?

Nerve endings and receptors detect touch, pressure, and pain.

What is excretion through the skin?

Removing water, salts, and waste products through sweat.

How does the skin help immunity?

Certain epidermal cells help defend the body against harmful substances and microorganisms.

How does the skin produce vitamin D?

UV radiation from sunlight triggers vitamin D production in the skin.

Why is vitamin D important?

It helps the body absorb calcium.

What are sebaceous glands?

Oil-producing glands usually associated with hair follicles.

What do sebaceous glands secrete?

Sebum.

What is sebum?

An oily substance that helps protect and moisturize the skin and hair.

What are the functions of sebum?

Keeps skin soft, prevents hair from drying out, and inhibits some bacterial growth.

What are sudoriferous glands?

Sweat glands that produce perspiration.

What is perspiration?

Sweat produced by sudoriferous glands.

What is sweat mainly made of?

Water and salts, along with small amounts of other substances and wastes.

What is the main function of sweat?

Regulates body temperature through evaporation.

How does sweat cool the body?

Evaporation removes heat from the skin.

What is another function of sweat?

Helps eliminate small amounts of waste products.

What is the difference between sebaceous and sudoriferous glands?

Sebaceous glands produce oil; sudoriferous glands produce sweat.

What is the difference between mucous and serous membranes?

Mucous membranes line cavities open to the exterior; serous membranes line closed cavities and cover organs.

What is the difference between serous and synovial membranes?

Serous membranes reduce friction between organs; synovial membranes lubricate movable joints.

What is the difference between the parietal and visceral layers?

Parietal attaches to the cavity wall; visceral attaches to the organ.

Epidermis

The outermost, thin layer of skin

Avascular

Without blood vessels

Keratinocyte

A skin cell that produces keratin to protect and waterproof the skin

Melanocyte

A skin cell that produces melanin, the pigment that gives skin its color

Dermis

The layer of skin beneath the epidermis that contains nerves, blood vessels, and glands

Subcutaneous Layer (Hypodermis)

The layer beneath the dermis that attaches skin to underlying structures and stores fat

Adipose Tissue

Body tissue that stores fat

Collagen

A protein that provides strength and support to the skin

Elastin

A protein that allows skin to stretch and return to its original shape

Acne

An inflammatory condition of hair follicles and sebaceous glands that causes pimples

Sebaceous Glands

Glands that produce an oily substance called sebum

Sebum

An oily substance produced by sebaceous glands

Skin Cancer

Uncontrolled growth of abnormal skin cells

ABCD Method

A method for checking skin lesions: Asymmetry, Border, Color, and Diameter

Asymmetry

When the two halves of a mole or lesion do not match

Basal Cell Carcinoma

A slow-growing skin cancer that begins in basal cells

Squamous Cell Carcinoma

A skin cancer that begins in squamous cells and can invade nearby tissues

Malignant Melanoma

A serious skin cancer that develops from melanocytes and can spread to other parts of the body

Decubitus Ulcer

A pressure sore caused by prolonged pressure on the skin, often over bony areas

Pressure Sore (Bed Sore)

Another name for a decubitus ulcer

Metastasis

The spread of cancer from its original site to other parts of the body