Integument Overview
Name at least one organ/accessory structures of the integumentary system.
Organ: skin
Accessory structures: hair, nails, glands, blood vessels, muscles and nerves
5 layers in thick skin and 4 layers in thin skin
How many layers does the dermis have?
2 layers
Give one example of an exocrine gland, and briefly describe its function.
Sebaceous = sebum secretion, Sudoriferous (eccrine/apocrine) = sweat secretion, Ceruminous = ear wax, Mammary = breast milk
What is one simple thing we can do to prevent skin cancer?
Apply sunscreen! Sunscreen is like a "bullet proof vest" that absorbs ultraviolent radiation from the sun, so it doesn't come in direct contact with your skin (epidermis).
How does the integumentary system maintain the body's integrity?
It serves a a form of protection via physical, chemical, and biological barriers. -- Ex: sweat glands regulate temperature to prevent body from overheating -- Ex: skin and hair provide barriers that protect internal organs
The stratum lucidum is present in which parts of the body?
Palms, palmar regions of the fingers, toes & soles -- these are the only parts that contain a 5-layer epidermis
What types of connective tissue fibers are found in the dermis?
collagen and elastic fibers
How do exocrine glands differ from endocrine glands?
Endocrine ducts secrete their substances (hormone) into the blood, while exocrine glands contain ducts that carry their secretory substances to the surfaces.
The arrector pili is an involuntary muscle that causes what?
Goose bumps
What are the layers of the skin?
Epidermis and dermis -- hypodermis is NOT part of the skin.
How does a a first-degree burn differ from a second-degree burn?
First-degree burns only affect the epidermis while second-degree burns affect the epidermis and the dermis.
Name the two layers of the dermis from superficial to deep.
Papillary layer = superficial, Reticular layer = deep
What is the function of the ceruminous gland?
It produces waxy substances to protect the ear canal from physical damage, microbial invasion, and debris.
Adipose tissues are found in which layer of the integumentary system?
Hypodermis
Vitamin D production starts in the skin. The liver then converts it to its active form, calcitrol, which is then secreted by the kidneys when calcium absorption is low.
Which layer of the epidermis are melanocytes found? Describe how the number of melanocytes differ from person to person.
Melanocytes are found in the stratum basale aka stratum germinativum. Each person has the same amount of melanocytes but the activity and amount of melanin produced differs and thus determines skin color.
What is the function of the meissner corpuscle found in the papillary layer of the dermis?
Functions to transmit sensations of touch
Describe the similarities and differences between eccrine and apocrine sweat glands.
Similarities = both secrete sweat; Differences: Eccrine functions to regulate body temp via evaporation. It has an extensive distribution. Apocrine have a limited distribution and its responsible for the sticky, cloudy odor from our axilla.
How do henna tattoos differ from real ink tattoos?
Name all four functions of the integumentary system.
(1) Protection via physical, chemical, and biological barriers (2) Maintains temperature (3) Vitamin D synthesis starts in the skin. (4) Provides sensory information = touch, pressure, vibration, tickle, heat, cold, and pain arise in skin.
List the 5 layers of the epidermis from SUPERFICIAL to DEEP.
Stratum corneum, stratum lucidum, stratum granulosum, stratum spinosum, stratum basale (aka stratum germinativum)
"Come Let's Get Some Beer"
What are epidermal ridges? Describe its function.
Epidermal ridges are found in the papillary layer of the dermis. They are downward projection of epidermis into dermis between the dermal papillae, and they function to increase surface area of epidermis which helps with grip of foot and hand.
Name and describe all 4 exocrine glands we covered in lecture.
Sebaceous = secretes sebum to moisten hair, waterproofs, and soften skin; Sudoriferous = sweat galnds, Ceruminous = secrete ear wax for protection, Mammary glands = secretes breast milk that contains immune cells
What the 3 skin cancers that were introduced in lecture. Which of the 3 is the most aggressive and why?
Basal cell carcinoma, Squamous cell carcinoma, and malignant melanoma; Malignant melanoma is the most aggressive because of its ability to spread and metastasize.