Skin Layers
What is the largest organ in the human body?
Skin
Which epidermal cells produce the protein keratin?
Keratinocytes
What is the visible part of the hair located above the skin's surface?
Hair shaft
What is another name for sweat glands?
Sudoriferous glands
What type of body membrane forms the skin?
Cutaneous membrane
What degree of burn affects only the epidermis and commonly causes redness, like a mild sunburn?
First-degree burn
What are the two main layers of the skin?
Epidermis and dermis
Which cells produce melanin, the pigment responsible for skin, hair, and eye color?
Melanocytes
What is the white, crescent-shaped area at the base of a fingernail called?
Lunula
What type of glands produce sebum, the oil that lubricates skin and hair?
Sebaceous glands
Which membrane lines body cavities that open to the outside of the body, such as the digestive and respiratory tracts?
Mucous membrane
What degree of burn affects the epidermis and upper dermis and typically causes painful blisters?
Second-degree burn
What is the name of the fatty tissue LAYER located beneath the skin called?
Hypodermis (subcutaneous tissue)
Which epidermal cells are responsible for detecting light touch?
Merkel cells
What is the name of the tunnel in the skin from which hair grows?
Hair follicle
What small muscles contract to cause goosebumps?
Arrector pili muscles
Which type of connective tissue membrane lines joint cavities and secretes lubricating fluid?
Synovial membrane
What common skin condition involves inflammation or infection associated with sebaceous glands and produces pimples?
Acne
Which layer of the skin is avascular, meaning it has no blood vessels?
Epidermis
Which immune cells are also known as dendritic cells and originate in the bone marrow?
Langerhans cells
What is the clear layer of skin along the bottom of the nail, commonly called the cuticle?
Eponychium
Which type of sweat gland is most numerous and helps prevent overheating?
Eccrine glands
Which serous membrane surrounds the lungs?
Pleura
What type of skin cancer develops from melanocytes?
Malignant melanoma
Which layer of the epidermis contains a single row of dividing stem cells that produce new keratinocytes?
Stratum basale
In which epidermal layer are melanocytes found?
Stratum basale
Which type of hair is fine, light-colored, and commonly referred to as peach fuzz?
Vellus hair
Which sensory receptors detect deep pressure and vibrations?
Pacinian corpuscles
Which serous membrane surrounds the heart?
Pericardium
What is the most immediate life-threatening concern following a massive third-degree burn?
Fluid loss leading to dehydration and electrolyte imbalance
Identify the epidermal layer that contains 20–30 layers of dead, flattened, anucleate keratinocytes and protects against abrasion and penetration.
Stratum corneum
What structures connect keratinocytes in the stratum spinosum and give them their spiny appearance?
Desmosomes
What is the name of the structure responsible for producing new nail cells and allowing the nail to grow?
Nail matrix
Which sweat glands become active at puberty, are concentrated in the armpits and genital regions, and produce thicker sweat containing fats?
Apocrine glands
What is the difference between the parietal and visceral layers of a serous membrane?
Parietal lines the cavity wall; visceral covers the organ
A patient has a burn that destroys the entire thickness of the skin, appears white or blackened, and may not be painful because nerve endings are destroyed. What degree is it, and what treatment may be needed?
Third-degree (full-thickness) burn; skin grafting
Name the five layers of the epidermis from superficial to deep.
Stratum corneum, lucidum, granulosum, spinosum, and basale
Which epidermal layer contains keratinocytes that produce keratohyalin granules and release lamellar bodies to help waterproof the skin?
Stratum granulosum
During puberty, a male begins developing darker, thicker hair on his face, underarms, and pubic region. What type of hair replaces the fine, peach-fuzz-like hair in these areas?
Terminal hair replaces vellus hair.
Name the three sensory receptors or structures responsible for light touch, deep pressure and vibration, and pain and temperature, respectively.
Meissner's corpuscles, Pacinian corpuscles, and free nerve endings
Identify the three major serous membranes and the body regions or organs associated with each.
Pleura: lungs; pericardium: heart; peritoneum: abdominal cavity and its organs
A patient notices a mole with an uneven shape, irregular borders, multiple colors, and a diameter greater than 6 mm. What skin cancer warning system identifies these four characteristics? Name all four.
ABCD rule for melanoma: Asymmetry, Border irregularity, Color variation, Diameter