Which cell is only found in the stratum spinosum and the stratum granulosum?
Dendritic Cells
The ____ System's major contribution is that it acts as a a barrier between the environment and the body
Integumentary
The initial step in the synthesis of the hormone known as calcitriol demonstrates the interaction of multiple organ systems, as in this example, where the ____ system requires proper functioning of the integumentary system.
Endocrine
Facial expressions require the integration of the ___ system in order to pull on skin attachments and create movement
Muscular
An example of ___ system interactions with the skin is the large number of sensory receptors that function to provide communication between the environment and body
Nervous
By serving as a blood reservoir, the skin can support the function of the ___ system by diverting blood to or from internal organs as neccessary
Circulatory
Dendritic cells located in the epidermis function to support the ____ system by detecting and altering the body to infectious or harmful agents
Lymphatic
Accessory structures of the skin, such as nose hairs, serve the ____ system by providing a mechanical filter against large objects entering the body
Respiratory
Active forms of vitamin D, as produced by the skin, improve the absorption of calcium from the ____ system
Digestive
As secreted in sweat, the skin aids the ____ system in ridding the body of metabolic wastes and excess electrolytes
urinary
Skin contains keratin and desmosomes that confer a mechanical strength to the epidermis which ___ such as punctures and abrasions
Resists mechanical traumas
As a result of impermeable cellular junctions and water-proofing lipids, the epidermis functions in _____
Creating a barrier to some fluds
The skin assists endocrine function by playing a role in ____ which is needed for calcium homeostasis
Vitamin-D synthesis
Because it houses many nerve endings and sensory organs, the skin is responsible for much of our ____
Sensation
Through vasodilation in times of excessive heat, and vasoconstriction during times of cold, the blood flow to the dermis aids the body through ___
Thermoregulation
Skeletal muscle attachments to facial structures produce a wide variety of expressions and ____ with other individuals
Produce nonverbal communication
The ____ is made up of multiple layers of dead keratinocytes that regularly exfoliate
Stratum corneum
The next layer is the _____ , which is present only on soles of the feet, hands, fingers, and toes
Stratum lucidum
The ____ is named for the presence of dark staining keratohyalin granules which bind the cytoskeletal keratin filaments together.
Stratum Granulosum
Towards the apical surface, in the ____ , the keratinocytes cease cell division, while at deeper regions, they can still undergo mitosis
Stratum spinosum
Comprised of viable, cuboidal and columnar cells, the ___ contains the keratinocyte stem cells that replenish the exfoliated cells at the surface
Stratum basale
Fingerprints are caused by ____
Friction ridges
When you make a fist, your finger joints move at ____ in the skin on the anterior surface of the hand
Felxion creases
___ are flat, melanized patches that vary heredity and sun exposure
Freckles
___ are elevated patched if melanized skin
Moles
A reddish birthmark made of benign tumors of capillaries is called a(n) ___
Hemangioma
Which of the following is not a type of hair?
Keratin
Mammary glands are modified ____ sweat glands and can be found in the ____
Apocrine; Breasts
Males do not have mammary glands because thy are only found in ___ and pregnant women
Lactating
Mammary glands produce ___ so a mother can nourish a newly born infant
Milk
The milk travels through ___ and out of the ____ for efficient conveyance to the newborn
Ducts; Nipple
____ arises from pigment-producing ____ and is the deadliest form of skin cancer if it spreads
Melanoma; Melanocytes
______ arises from ____ of the stratum spinosum and sometimes spreads to the lymph nodes
Squamous cell carcinoma; Keratinocytes
___ arises from the deepest layer of the skin's ____ and rarely metastisizes
Basal cell carcinoma; Epidermis
The ____ contains mitotic cells
Nail matrix
The ___ is deep to the eponychium
Nail root
The ___ contains layers of compacted, highly keratinized epithelial cells
Nail body
The ___ is part of the nail that can overhang the tip of the finger
Free edge of the nail
The stratum ____ is a single layer of columnar or high cuboidal cells resting on a basement membrane
Basale
The stratum ____ is composed of many layers of keratinocytes that are firmly attached to each other by desmosomes. This layer also contains dendritic cells.
Spinosum
The stratum ____ is composed of 3 - 5 layers of flattened keratinocytes containing dark staining keratohyalin granules
Granulosum
The stratum ____ is a translucent layer composed of 3 - 5 layers of keratinocytes without nuclei or organelles
Lucidum
The stratum ____ is composed of up to 30 layers of cornified, dead cells
Corneum
Why are injections frequently administered into the hypodermis?
The subcutaneous tissue is highly vascular
Why are the cells in the stratum corneum dead?
Epidermal cells dies as they move away from their nutrient supply in the dermis
Dermal papillae are numerous in palmar and plantar skin but few in number in the skin of the face and abdomen. What do you think is the functional significance of this difference?
Dermal papillae help strengthen the connection between the dermis and epidermis and help prevent friction - related damage in high use areas
Hypernatremia occurs when the sodium concentration in the blood gets too high. Why might this be a concern in patient with extensive third-degree burns?
Disruption of the epidermal water barrier can cause severe dehydration
This picture shows two different types of cutaneous glands. What do apocrine glands produce?
Sweat
Sebaceous glands (shown here) secrete a product called sebum. What is sebum?
An oily substance that helps moisturize the skin and hair
Use this picture to carefully examine the structure of the apocrine and sebaceous gland ducts. Which of the following statements is true?
Both types of glands release their products into hair follicles
Use this picture to carefully examine the lumina of apocrine and sebaceous glands. Which of the following statements is true? (Note: "lumina" is the pleural form of "lumen.")
The apocrine gland has a clear lumen, the sebaceous gland does not.
The secretory portion of apocrine sweat glands is made up of _____ epithelium, and the secretory portion of sebaceous glands is made up of ____ epithelium
Simple cuboidal; Stratified Cuboidal
The papillary layer of the dermis is made up of ____, and the reticular layer of the dermis is made up of ____
Areolar tissue; Dense irregular connective tissue
Use this picture to compare tissue structure in the papillary and reticular layers of the dermis. Which of the following best describes your observations?
The reticular layer is thicker and more fibrous. The papillary layer is a thinner zone of more loosely organized tissue containing many "wandering" white blood cells
How does the structure of the reticular dermis relate to its functional properties?
Bundles of densely packed collagen fibers help the skin withstand stretching in many different directions
How does the structure of the papillary dermis relate to its functional properties?
The loosely organized tissue allows the diffusion of nutrients and the movement of white blood cells between the dermis and the avascular epidermis
Four of the five statements below are common misconceptions about hair and fingernails. Which one is true?
Each scalp hair can grow for several years before falling out
Where are the cutaneous blood vessels and nerve fibers located in this picture?
Both are in the dermis. Neither one is found in the epidermis
Based on your answer to the previous question, which of the following seems most likely?
Oxygen and nutrients must diffuse into the avascular epidermis from nearby dermis
Consider your answer to the previous question. What impact might this have on the life history of keratinocytes?
Keratinocytes in the deepest layers of the epidermis (close to the dermis) are the only ones that receive enough nutrients and oxygen to undergo mitosis
Keep in mind the location of the nerve fibers in this picture. What impact might this have on cutaneous sensation?
Unlike first-degree burns, third-degree burns destroy the nerve fibers in the dermis and may therefore be painless