ap exam 3 unit 5

Identify the substance present in skin which absorbs ultraviolet (UV) radiation to protect deeper tissue from damage?

melanin

Goose bumps are caused by contraction of what muscle?

arrector pili

In the hair Growth Cycle, what is the stage during which the hair falls out?

telogen stage

The portion of the hair that is shaped like an onion deep in dermis where cell growth occurs is called what?

bulb

The skin is an organ composed of two tissue types, an epithelium and a connective tissue component. (T/F)

True

Which one of the following types of glands contributes to thermoregulation?

merocrine gland

Which epidermal cell layer consists of living keratinocytes held together by desmosomes?

stratum spinosum

Fur in mammals is considered what type of hair?

terminal hair

The very thin, unpigmented hair covering the fetus is called what?

Lanugo

Which one of the following is an immune cell routinely found in the epidermis?

Langerhans cell

If vasodilation of peripheral blood vessels and sweating occurs, what condition below is indicated?

hyperthermia

The cells forming the hair arise from what region?

matrix

A precursor form of which one of the following vitamins is produced in the skin?

vitamin D

Which statement below best describes how epidermal cells receive nutrient?

nutrient diffuses from dermal capillaries toward the epidermis

What epidermal layer contributes most directly to formation of dandruff?

stratum corneum

What type of connective tissue forms the portion of the dermis termed the reticular region?

dense connective tissue

What oily substances secreted onto skin help to prevent water from being absorbed into the skin and excessive evaporation of water from the skin?

Glycolipids

In the region of the ear, modified sweat glands produce ear wax which is called what?

cerumen

Starting at the centermost area of the hair shaft and going outward, pick the correct sequence of layers from the list below.

medulla, cortex, cuticle, epithelial root sheath, dermal root sheath

Which epidermal layer contains epidermal stem cells?

stratum germinativum

Which one of the following best approximates the proportion of total body weight that is accounted for by the skin?

15%

The stage at which the cells in the hair matrix are dividing is termed what stage?

anagen stage

Which cells in the epidermis are known as tactile cells and are associated with sensory nerve endings?

Merkel cells

Identify the salty, acidic substance that is secreted onto the skin and helps inhibit microbial growth?

sweat

The majority of heat is lost from the body through which one of the following organs?

skin

The bulb portion of the dermal root sheath has what function?

contains blood vessels to nourish hair growth

The active form of vitamin D is associated with the regulation of which one of the following ions?

calcium

What is the name of the process which describes sweat absorbing heat and becoming vapor moving away from the skin?

evaporation

What type of connective tissue forms the portion of the dermis just beneath the epidermis?

areolar connective tissue

During which phase in deep wound healing does hemostasis play a role?

inflammatory phase

Which one of the following best approximates the proportion of total heat loss which occurs through the skin?

80%

Which one of the following is the term used for the white, half-moon shaped area at the proximal end of the nail?

lunule

What area of the body indicated below is the stratum corneum thickest?

soles of the feet

The stratum lucidum epidermal cell layer is especially noticeable in the hairy skin areas of the body. (T/F)

False

What type of skin sensory neurons are stimulated by extreme temperature, physical, mechanical or chemical irritation?

Nociceptor

Which one of the following temperatures most closely approximates normal core body temperature?

98.6 degrees F

Rarely, excess hair covers almost the entire body as a fur sometimes giving this condition the name, werewolf syndrome, but the medical name for this genetic condition is what?

hypertrichosis

Which one of the following best approximates the time required for a cell to transition from the basal layer towards the apical layers, become keratinized, and finally be sloughed off?

four weeks

Choose from the list below the name for the free edge of the nail made up of thickened stratum corneum and serves to secure the nail to the fingertip.

hyponychium

Which sweat glands develop during puberty and are located mainly in the armpits and anogenital areas?

apocrine gland

Which skin “appendages” listed below are produced by the epidermis?

all of the listed choices (hair, nails, sweat glands, sebaceous glands)

The disease, Xeroderma pigmentosum, is a genetic disease caused by what defect?

defective DNA repair enzymes

The secretory portion of the apocrine gland contains mainly a watery solution that helps to contribute to thermoregulation. (T/F)


False

The stage at which the cells in the hair matrix reduces their metabolic activity with hair falling out in several months is called what stage?

telogen stage

The beginning of keratinocyte death and presence of keratohyalin and lamellar granules are indicative of keratinocytes in which epidermal layer?

stratum granulosum

If you perceive pain in the area of skin located just below your sternum, from what organ might this pain be coming from?

intestine

What term describes the condition when body temperature drops below normal?

hypothermia

Which nail region describes the nail visible on the dorsal surface of the distal end of the digit?

plate

What is the name of the short, fine hair that covers the body of the newly born infant?

vellus

In which epidermal layer would you find keratinization occurring?

stratum granulosum

The skin is considered an epithelium since it covers an external space. (T/F)

False

In the Hair Growth Cycle, what is the stage during which hair growth occurs?

anagen stage

Which type of sweat gland secretes a substance that bacteria can act on to produce body odor?

apocrine gland

Referred pain describes the feeling of pain in one’s left chest and arm when having a heart attack.

True

There appears to be a link between fingerprint patterns and certain genetic abnormalities such as Down’s syndrome. (T/F)

True

What is the name of the process which describes warm air around the body moving away from the body surface to be replaced by cooler air?

convection

Which skin receptor is sensitive to touch and pressure?

Merkel discs

What important discovery did Henry Faulds, a Scottish medical missionary, make in 1880 that is still important today?

surface ridges on fingertips do not change over a lifetime

In thermoreception, the "warm" receptors are located in the dermis of the skin. (T/F)

True

In thermoreception, the "cold" receptors are located in the dermis of the skin. (T/F)

False

The ability of skin to be able to recoil back to its original state is due to what fiber(s)?

elastic

In the Hair Growth Cycle, what is the stage during which the cells of the hair matrix stop dividing and metabolic activity ceases?

catagen stage

The property of strength and resistance to stretching is due to the presence of what fiber(s) in the dermis?

collagen

At puberty, what type of hair grows in the area of the face (beard) in males, and in the genital region and axillary region of males and females?

terminal hair

The stratum basale layer of cells in the epidermis is also known by what other name due to its high level of cell division?

stratum germinativum

Keratinocyte death begins to occur in which epidermal layer?

stratum granulosum

Lamellar granules found in the keratinocytes of the stratum granulosum epidermal layer are composed of what substance?

glycolipid

Which skin receptor is sensitive to vibration and pressure?

Pacinian corpuscles

Which one of the following best describes an injury requiring deep wound healing?

an injury reaching into the dermis

The sub-layer of the dermis which contains finger-like protrusions into the epidermis is called what?

papillary region

What type of sweat gland is activated by the sympathetic nervous system in response to hyperthermia?

merocrine gland

In hypothermia, what might one expect the arector pili muscles in the skin to do?

contract pulling hair up

Which nail region is formed from keratocytes surrounding the bail root from which the nail grows?

matrix

Which epidermal layer is lacking in hairy skin?

stratum lucidum

The hypodermis is not considered part of the dermis.(T/F)

True

Hair follicles and sweat glands are found in the dermis and are considered to be of dermal origin. (T/F)

False

Which one of the following cell types produces scar tissue?

fibroblasts

Which region of the dermis is the largest region?

reticular

When our hands get sweaty during a tension-filled moment, which type of sweat gland is producing the excess sweat?

merocrine gland

Which epidermal layer is first involved in the repair process?

stratum basale

If you perceive pain in the area just below your rib cage on the anterior or ventral surface, what body organ might be from where the pain arises.

liver

Which one of the following epidermal strata contains the most live cells?

stratum basale

Which nail region is formed from the thickened skin area made from the stratum corneum which secures the nail to the fingertip?

hyponychium

Which one of the following is the most common type of cell in the epidermis?

keratinocyte

The portion of the hair which is embedded deep in the dermis is called what?

root

Choose the correct order of the layers in the epidermis from superficial to deep.

stratum corneum, stratum lucidum, stratum granulosum, stratum spinosum, stratum basale

What is name of the process which describes the transfer of heat when vasodilation of blood vessels near the skin transfers heat to the external atmosphere?

conduction

Cells involved in the healing of the epidermis are produced by cell division occurring in which one of the following epidermal strata?

stratum basale

Which one of the following is most significant determinant of skin color?

amount of melanin produced

Which nail region shows a white, half-moon shaped area in the proximal region of the nail?

lunule

The stage at which the cells in the hair matrix stop dividing is termed what stage?

catagen stage

Which skin receptor is sensitive to touch, pressure and vibration?

Meissner’s corpuscles

Which nail region is formed from the connective tissue underneath the nail which makes it thicker and stronger as the nail grows?

bed

What type of fiber(s) are found in the connective tissue forming the dermis?

collagen and elastic