Integumentary System Quiz

Questions and Answers

What structures are included in the integumentary system?

The integumentary system consists of the skin, hair, oil and sweat glands, nails, and sensory receptors.

How does the process of keratinization occur?

Newly formed cells in the stratum basale are pushed to the surface, accumulating keratin. They undergo apoptosis, slough off, and are replaced by underlying cells. The process takes about four weeks.

What are the functions of the epidermis?

Prevents water loss and entry of pathogens, continuous mitosis, produces antimicrobial defensins, changes cholesterol to vitamin D, and protects living skin layers from UV rays.

What are the functions of the dermis?

Contains capillaries, provides insulation, protects ends of fingers and toes, detects changes in senses, produces sebum, and helps regulate body temperature. Signup and view all the answers

How are epidermal ridges formed?

They are produced during fetal development as projections of the epidermis into the dermis, increasing surface area and grip. Signup and view all the answers

What are the three pigments in the skin and how do they contribute to skin color?

Melanin, hemoglobin, and carotene contribute to skin color; melanin varies the skin color from yellow to black, hemoglobin gives a red color, and carotene is a yellow-orange pigment. Signup and view all the answers

Describe the structure of a hair.

Each hair is composed of columns of dead, keratinized epidermal cells bonded by proteins and emerges at an angle to the skin surface. Signup and view all the answers

What causes 'goose bumps'?

'Goose bumps' occur when the arrector pili muscles contract, pulling hair shafts perpendicular to the skin due to stress or cold. Signup and view all the answers

Contrast the locations and functions of sebaceous, sudoriferous, and ceruminous glands.

Sebaceous glands produce sebum, sudoriferous glands produce sweaty for cooling, and ceruminous glands produce cerumen for ear protection. Signup and view all the answers

Describe the parts of a nail.

Nails are hard, dead keratinized epidermal cells on the dorsal surfaces of the digits. Signup and view all the answers

Study Notes

Integumentary System Overview

Comprises skin, hair, oil and sweat glands, nails, and sensory receptors.

Keratinization Process

Cells in stratum basale gradually migrate to skin surface, accumulating keratin.
This process involves cell death (apoptosis) and takes about four weeks for completion in a typical epidermis of 0.1 mm thickness.

Functions of the Epidermis

Stratum corneum prevents water loss and entry of pathogens if unbroken.
Stratum germinativum continually produces new cells; synthesizes vitamin D when exposed to UV light.
Langerhans cells act in immune response through phagocytosis of foreign materials.
Merkel cells function as touch receptors.
Melanocytes produce melanin, protecting deeper skin layers from UV radiation.

Functions of the Dermis

Papillary layer contains capillaries nourishing the stratum germinativum.
Hair follicles prevent dust entry and provide insulation.
Nails protect the tips of fingers and toes from mechanical damage.
Receptors within dermis enable detection of touch, pressure, heat, cold, itch, and pain.
Sebaceous glands secrete sebum to maintain skin and hair moisture while inhibiting bacteria.
Eccrine sweat glands produce sweat to cool the body.
Arterioles adapt by dilating to lose heat or constricting in cold to conserve body heat.

Formation of Epidermal Ridges

Form during fetal development as the epidermis projects into the dermis.
Increase surface area and grip, contributing to fingerprints as sweat pores open on ridges.

Skin Pigments and Skin Color

Melanin (dark shades), hemoglobin (red from blood), and carotene (yellow-orange) influence skin color.
The level of melanin dictates skin tone from pale yellow to deep brown.
Carotene is stored in skin layers, particularly after high dietary intake.

Hair Structure and Goosebumps

Hair consists of dead, keratinized cells; emerges at an angle from the skin.
Goosebumps occur when arrector pili muscles contract due to stress, positioning hair shafts upright.