Quiz 2

What layer(s) of the skin is (are) damaged in a second-degree burn?

The epidermis and the superficial regions of the dermis are damaged

Apocrine glands, which begin to function at puberty under hormonal influence, seem to play little role in thermoregulation. Where would we find these glands in the human body?

in the axillary and anogenital area

Male pattern baldness has a genetic switch that turns on in response to ________.

male hormones

Which skin pigment is made in the skin itself?

melanin

Susan sat out in the sun watching a baseball game. She developed small blisters on her unprotected shoulders and neck. What type of burn is represented by the formation of the blisters?

second degree burn

Which of the following is a metabolic function of skin?

synthesis of a vitamin D precursor

The dermis has two major layers; which of the following constitutes 80% of the dermis and is responsible for the tension lines in the skin?

the reticular layer

Robert, a surfer, has a mole that has changed its shape and size. His doctor, applying the ABCD(E) rule, diagnosed a melanoma. What do the letters ABCD(E) represent?

A = asymmetry, B = border, C = color, D = diameter, E = elevation

Albinos commonly contract skin cancer. What seems to be the reason, and what can be done to reduce the risk of skin cancer?

Albinos lack melanin and have thus lost their main defense against the damaging UV light that can cause skin cancer. They can cover all body areas and avoid bright sunlight.

We are told that every surface we touch is teeming with bacterial cells, and bacteria are found in the pools we swim in, the water we wash with, and on the hands of friends. Why are we not inundated with bacterial infections on our skin?

All of these answers are correct. A. The low pH of the skin secretions retards the multiplication of bacteria on the skin. B. Many bacteria are killed by bactericidal substances in the sebum and sweat. C. Not all bacteria are harmful or thrive on the skin.

Sudoriferous glands vary in distribution over the surface of the body. Which of the following is correct?

Ceruminous glands secrete cerumen, which is thought to deter insects.

Dermis is the papillary layer, reticular layer

Dermis

Destruction of the matrix of the hair bulb would result in its inability to produce oil.

False

Hair and nails are made primarily of calcium.

False

Joe just burned himself on a hot pot. A blister forms and the burn is painful. Joe's burn would best be described as a third-degree burn.

False

The hypodermis is composed of adipose and dense connective tissue.

False

The protein found in large amounts in the outermost layer of epidermal cells is collagen.

False

The reason that the nail bed appears pink is the presence of a large number of melanocytes in the underlying dermis.

False

The skin is not able to receive stimuli because the cells of the epidermis are not living and therefore there are no sensory receptors in the skin.

False

When an individual is exposed to extremely low air temperatures, the dermal blood vessels will dilate so that blood and heat will be dissipated.

False

In thick skin, you would expect the __________ to be more prominent than it is in thin skin

Stratum Lucidum

Sweat is secreted by:

Sudoriferous glands

Despite its apparent durability, the dermis is subject to tearing. How might a person know that the dermis has been stretched and/or torn?

The appearance of visible, silvery-white scars is an indication of stretching of the dermis.

Why might soap that has an alkaline base not be healthy for some patients to use daily?

The base will neutralize the acid on the skin that retards the growth of bacteria, and the removal of the normal microbiota of skin will leave the person exposed to opportunistic pathogens

What protects the fetus's skin within the water-filled amniotic sac?

Vernix caseosa

The composition of the secretions of the eccrine glands is ________.

99% water, sodium chloride, trace amounts of wastes, and vitamin C

In addition to protection (physical and chemical barrier), the skin serves other functions. Which of the following is another vital function of the skin?

It converts modified epidermal cholesterol to a vitamin D precursor important to calcium metabolism.

Which of the following cutaneous receptors is specialized for the reception of touch or light pressure?

Meissner's corpuscles

What layer of the dermis is directly below the epidermis?

Papillary layer

Which of the following is not a layer of the epidermis?

Papillary layer

What is the role of the hair matrix?

The hair matrix produces hair.

John, a younger teenager, notices that he is experiencing a lot of pimples and blackheads, which frequently become infected. What is causing this problem?

The hormonal changes are causing the sebaceous glands to become overactive, resulting in them becoming clogged and infected.

What part of the dermis gives rise to friction ridges (fingerprints)?

The papillary layer

The design of a person's epidermal ridges is determined by the manner in which the papillae rest upon the dermal ridges to produce the specific pattern known as handprints, footprints, and fingerprints. Which of the following statements is true regarding these prints or ridges?

They are genetically determined, therefore unique to each person.

Stratum Corneum

Top

A physician is often able to detect homeostatic imbalances in the body by observing changes in the skin color.

True

Our skin helps us to regulate our body temperature

True

Regardless of race, all human beings have about the same number of melanocytes.

True

The biggest risk factor for the development of skin cancer is excessive exposure to ultraviolet light.

True

The dense fibrous connective tissue portion of the skin is located in the reticular region of the dermis.

True

The dermis is rich in blood vessels and nerve fibers.

True

The epidermis uses a modified form of cholesterol to produce a vitamin D precursor.

True

The most dangerous skin cancer is cancer of the melanocytes.

True

The pinkish hue of individuals with fair skin is the result of the crimson color of oxygenated hemoglobin (contained in red blood cells) circulating in the dermal capillaries and reflecting through the epidermis.

True

Sam is so cold that he has "goose bumps." What causes goose bumps?

arrector pili muscles pulling hair follicles into an upright position

The most common type of skin cancer is:

basal cell carcinoma

Burns are devastating and debilitating because of loss of fluids and electrolytes from the body. How do physicians estimate the extent of burn damage associated with such dangerous fluid loss?

by using the "rule of nines"

What is the first threat to life from a massive third-degree burn?

catastrophic fluid loss

A needle would pierce the epidermal layers of the forearm in which order?

corneum, granulosum, spinosum, basale

The papillary layer of the dermis is connective tissue heavily invested with blood vessels. The superficial surface has structures called:

dermal papillae.

Nutrients reach the surface of the skin (epidermis) through the process of ________.

diffusing through the tissue fluid from blood vessels in the dermis

Which skin appendages aid in cooling the skin when the body temperature or the external environmental temperature is high?

eccrine sweat glands