Ch. 5 Integumentary System Flashcards
The papillary layer of the dermis is most closely associated with which layer of the epidermis?
A. Stratum spinosum.
B. Stratum corneum.
C. Stratum granulosum.
D. Stratum basale.
D. Stratum basale
Explanation: The stratum basale is the deepest layer of the epidermis, directly interacting with the papillary layer of the dermis through dermal papillae, which strengthen the connection between the two layers.
A. Stratum spinosum – Located above the stratum basale, but not directly connected to the dermis.
B. Stratum corneum – The outermost layer of dead cells, far from the dermis.
C. Stratum granulosum – A middle layer involved in keratinization, not in direct contact with the dermis.
Langerhans cells are commonly found in the (BLANK).
A. Stratum spinosum.
B. Stratum corneum.
C. Stratum granulosum.
D. Stratum basale.
A. Stratum spinosum
Explanation: Langerhans cells are immune cells located in the stratum spinosum, where they function as macrophages, detecting and engulfing pathogens and debris.
B. Stratum corneum – The outermost layer of dead keratinized cells, lacking living immune cells.
C. Stratum granulosum – A layer involved in keratinization, not immune defense.
D. Stratum basale – Contains melanocytes and basal cells but is not the primary location of Langerhans cells.
The papillary and reticular layers of the dermis are composed mainly of (BLANK).
A. Melanocytes.
B. Keratinocytes.
C. Connective tissue.
D. Adipose tissue.
C. Connective tissue
Explanation: The papillary and reticular layers of the dermis are composed mainly of connective tissue, including collagen and elastin fibers, which provide strength, flexibility, and support.
A. Melanocytes – Pigment-producing cells found in the epidermis, not the dermis.
B. Keratinocytes – The main cells of the epidermis, responsible for producing keratin.
D. Adipose tissue – Found primarily in the hypodermis (subcutaneous layer), providing insulation and cushioning.
Collagen lends (BLANK) to the skin.
A. Elasticity.
B. Structure.
C. Color.
D. UV protection.
B. Structure
Explanation: Collagen provides strength and structural support to the skin, making it firm and resilient by maintaining its shape and integrity.
A. Elasticity – Provided mainly by elastin fibers, not collagen.
C. Color – Determined by melanin, produced by melanocytes in the epidermis.
D. UV protection – Primarily provided by melanin, not collagen.
The stratum (BLANK) has a grainy appearance due to further changes to the keratinocytes as they are pushed from the stratum spinosum.
A. Spinosum.
B. Basale.
C. Corneum.
D. Granulosum.
D. Granulosum
Explanation: The stratum granulosum has a grainy appearance due to the accumulation of keratohyalin and lamellar granules, which help in keratinization as cells move up from the stratum spinosum.
A. Spinosum – A layer below the granulosum, where keratinocytes begin to form desmosomes for strength and flexibility.
B. Basale – The deepest layer of the epidermis, responsible for cell generation and not involved in the grainy appearance.
C. Corneum – The outermost layer of dead, fully keratinized cells, lacking a grainy texture.
In response to stimuli from the sympathetic nervous system, the arrector pili (BLANK).
A. Are glands on the skin surface.
B. Can lead to excessive sweating.
C. Are responsible for goose bumps.
D. Secrete sebum.
C. Are responsible for goose bumps
Explanation: Arrector pili muscles are small smooth muscles attached to hair follicles that contract in response to cold or fear, pulling the hair upright and causing goose bumps.
A. Are glands on the skin surface – Arrector pili are muscles, not glands.
B. Can lead to excessive sweating – Sweating is controlled by sweat glands, not arrector pili muscles.
D. Secrete sebum – Sebum is secreted by sebaceous glands, not arrector pili muscles.
The hair matrix contains (BLANK).
A. The hair follicle.
B. The hair shaft.
C. The glassy membrane.
D. A layer of basal cells.
D. A layer of basal cells
Explanation: The hair matrix contains basal cells, which actively divide through mitosis to produce new hair cells, contributing to hair growth.
A. The hair follicle – The follicle is a structure that houses the hair root but is not part of the matrix itself.
B. The hair shaft – The visible part of the hair above the skin, produced by the matrix but not contained within it.
C. The glassy membrane – A thickened basement membrane surrounding the hair follicle, providing structural support but not involved in hair cell production.
Eccrine sweat glands (BLANK).
A. Are present on hair.
B. Are present in the skin throughout the body and produce watery sweat.
C. Produce sebum.
D. Act as a moisturizer.
B. Are present in the skin throughout the body and produce watery sweat
Explanation: Eccrine sweat glands are widely distributed across the body and primarily function in thermoregulation by producing watery sweat that helps cool the skin through evaporation.
A. Are present on hair – Eccrine glands open directly onto the skin surface, not associated with hair follicles.
C. Produce sebum – Sebum is produced by sebaceous glands, not eccrine sweat glands.
D. Act as a moisturizer – While sweat can hydrate the skin temporarily, eccrine glands are primarily for cooling, not moisturizing.
Sebaceous glands (BLANK).
A. Are a type of sweat gland.
B. Are associated with hair follicles.
C. May function
D. Release a watery solution of salt and metabolic waste.
B. Are associated with hair follicles.
Explanation:
Sebaceous glands produce sebum, an oily substance that lubricates and waterproofs the hair and skin, and they are typically found connected to hair follicles.
Incorrect Answers:
Are a type of sweat gland – Sebaceous glands produce oil (sebum), not sweat. May function in response to touch – Sebaceous glands do not respond to touch; they function mainly in lubrication. Release a watery solution of salt and metabolic waste – This describes eccrine sweat glands, not sebaceous glands.
Similar to the hair, nails grow continuously throughout our lives. Which of the following is furthest from the nail growth center?
A. Nail bed.
B. Hyponychium.
C. Nail root.
D. Eponychium.
B. Hyponychium.
Explanation: The hyponychium is the area of skin located beneath the free edge of the nail, making it the furthest from the nail growth center at the nail root.
Incorrect Answers:
A. Nail bed – Lies beneath the nail plate and supports nail growth but is closer to the root.
C. Nail root – The growth center where new nail cells are produced.
D. Eponychium – Also known as the cuticle, located near the nail root, not at the distal end.
Which term describes the active phase of the hair growth cycle?
A. Acne.
B. Albinism.
C. Apocrine.
D. Anagen.
D. Anagen.
Explanation: The anagen phase is the active growth stage of the hair cycle, where hair follicles produce new cells, resulting in continuous hair growth.
Incorrect Answers:
A. Acne – A skin condition caused by clogged pores and inflammation, unrelated to hair growth;
B. Albinism – A genetic disorder causing a lack of melanin, affecting hair, skin, and eye pigmentation;
C. Apocrine – A type of sweat gland found in areas like the armpits and groin, not involved in hair growth.
Which of the following is not a function of the hypodermis?
A. Protects underlying organs.
B. Helps maintain body temperature.
C. Source of blood vessels in the epidermis.
D. A site for long-term energy storage.
C. Source of blood vessels in the epidermis
Explanation: The epidermis is avascular (lacking blood vessels), meaning it does not receive blood supply directly from the hypodermis. Instead, nutrients diffuse from the underlying dermis.
Incorrect Answers:
A. Protects underlying organs – The hypodermis acts as a cushion, protecting deeper structures like muscles and bones.
B. Helps maintain body temperature – The adipose tissue in the hypodermis provides insulation, helping regulate body temperature.
C. A site for long-term energy storage – The hypodermis stores adipose (fat) tissue, serving as an energy reserve.
In humans, exposure of the skin to sunlight is required for (BLANK).
A. Vitamin D synthesis.
B. Arteriole constriction.
C. Folate production.
D. Thermoregulation.
A. Vitamin D synthesis.
Explanation: Sunlight exposure triggers the production of cholecalciferol (Vitamin D3) in the skin, which is later converted into active Vitamin D.
Incorrect Answers:
B. Arteriole constriction – Cold temperatures, not sunlight, cause arteriole constriction to reduce heat loss.
C. Folate production – Sunlight can degrade folate rather than promote its production.
D. Thermoregulation – Sunlight can influence body temperature, but thermoregulation is controlled by other mechanisms like sweating and blood vessel dilation.
One of the functions of the integumentary system is protection. Which of the following does not directly contribute to that function?
A. Stratum lucidum.
B. Desmosomes.
C. Folic acid synthesis.
D. Merkel cells.
C. Folic acid synthesis.
Explanation: Folic acid synthesis is important for DNA production and cell division but does not directly contribute to the protective function of the integumentary system.
Incorrect Answers:
A. Stratum lucidum – Provides an extra protective layer in thick skin, such as the palms and soles.
B. Desmosomes – Strong cell junctions that hold skin cells together, preventing mechanical damage and water loss.
D. Merkel cells – Sensory receptors in the skin that help detect touch and pressure, contributing to protective reflexes.
An individual using a sharp knife notices a small amount of blood where he just cut himself. Which of the following layers of skin did he have to cut into in order to bleed?
A. Stratum corneum.
B. Stratum basale.
C. Papillary dermis.
D. Stratum granulosum.
Correct Answer: C. Papillary dermis.
Explanation: The dermis contains blood vessels, so cutting into the papillary dermis (the upper layer of the dermis) causes bleeding.
Incorrect Answers:
A. Stratum corneum – The outermost layer of dead skin cells, with no blood vessels.
B. Stratum basale – Part of the epidermis, which is avascular, so cutting it would not cause bleeding.
D. Stratum granulosum – Also within the epidermis, meaning it lacks blood supply and would not bleed.
As you are walking down the beach, you see a dead, dry, shriveled-up fish. Which layer of your epidermis keeps you from drying out?
A. Stratum corneum.
B. Stratum basale.
C. Stratum spinosum.
D. Stratum granulosum.
A. Stratum corneum.
Explanation: The stratum corneum is the outermost layer of the epidermis, composed of dead, keratinized cells that form a waterproof barrier, preventing dehydration.
Incorrect Answers:
B. Stratum basale – The deepest layer of the epidermis, responsible for cell generation but not waterproofing.
C. Stratum spinosum – Provides structural support but does not prevent water loss.
D. Stratum granulosum – Plays a role in keratinization but is not the main barrier against dehydration.
If you cut yourself and bacteria enter the wound, which of the following cells would help get rid of the bacteria?
A. Merkel cells.
B. Keratinocytes.
C. Langerhans cells.
D. Melanocytes.
C. Langerhans cells.
Explanation: Langerhans cells are immune cells found in the stratum spinosum that detect and help eliminate bacteria by presenting antigens to the immune system.
Incorrect Answers:
A. Merkel cells – Sensory receptors responsible for touch detection, not immune defense.
B. Keratinocytes – Main skin cells that produce keratin, providing a physical barrier but not directly attacking bacteria.
D. Melanocytes – Produce melanin for UV protection but do not play a role in immune response.
In general, skin cancers (BLANK).
A. Are easily treatable and not a major health concern.
B. Occur due to poor hygiene.
C. Can be reduced by limiting exposure to the sun.
D. Affect only the epidermis.
C. Can be reduced by limiting exposure to the sun.
Explanation: UV radiation from the sun is a major cause of skin cancer, and reducing sun exposure (e.g., using sunscreen, wearing protective clothing) helps lower the risk.
Incorrect Answers:
A. Are easily treatable and not a major health concern – Some skin cancers, like melanoma, can be life-threatening if not treated early.
B. Occur due to poor hygiene – Skin cancer is caused by UV exposure, genetic factors, and carcinogens, not hygiene.
D. Affect only the epidermis – While they often begin in the epidermis, aggressive skin cancers can invade deeper tissues and spread.
Bedsores (BLANK).
A. Can be treated with topical moisturizers.
B. Can result from deep massages.
C. Are preventable by eliminating pressure points.
D. Are caused by dry skin.
C. Are preventable by eliminating pressure points.
Explanation: Bedsores (decubitus ulcers) develop from prolonged pressure that cuts off blood flow to the skin. Regular repositioning, cushioning, and reducing pressure points help prevent them.
Incorrect Answers:
A. Can be treated with topical moisturizers – Moisturizers may help with dry skin but do not heal or prevent bedsores.
B. Can result from deep massages – Deep massages do not cause bedsores; they result from prolonged pressure and poor circulation.
D. Are caused by dry skin – Bedsores are caused by prolonged pressure and reduced blood flow, not dryness.
An individual has spent too much time sunbathing. Not only is his skin painful to touch, but small blisters have appeared in the affected area. This indicates that he has damaged which layers of his skin?
A. Epidermis only.
B. Hypodermis only.
C. Epidermis and hypodermis.
D. Epidermis and dermis.
D. Epidermis and dermis.
Explanation: The presence of blisters indicates a second-degree burn, which damages both the epidermis and dermis.
Incorrect Answers:
A. Epidermis only – A first-degree burn (e.g., mild sunburn) affects only the epidermis and does not cause blisters.
B. Hypodermis only – The hypodermis is affected in third-degree burns, not in typical sunburn cases.
C. Epidermis and hypodermis – Second-degree burns do not reach the hypodermis; third-degree burns do.
After a skin injury, the body initiates a wound-healing response. The first step of this response is the formation of a blood clot to stop bleeding. Which of the following would be the next response?
A. Increased production of melanin by melanocytes.
B. Increased production of connective tissue.
C. An increase in Pacinian corpuscles around the wound.
D. An increased activity in the stratum lucidum.
B. Increased production of connective tissue.
Explanation: After a blood clot forms, fibroblasts migrate to the wound and produce collagen fibers, helping to rebuild and strengthen the damaged tissue.
Incorrect Answers:
A. Increased production of melanin by melanocytes – Melanin production is related to pigmentation, not wound healing.
C. An increase in Pacinian corpuscles around the wound – Pacinian corpuscles are deep pressure receptors and do not play a role in healing.
D. An increased activity in the stratum lucidum – The stratum lucidum is only found in thick skin (palms/soles) and is not involved in wound healing.
Squamous cell carcinomas are the second most common of the skin cancers and are capable of metastasizing if not treated. This cancer affects which cells?
A. Basal cells of the stratum basale.
B. Melanocytes of the stratum basale.
C. Keratinocytes of the stratum spinosum.
D. Langerhans cells of the stratum lucidum.
C. Keratinocytes of the stratum spinosum.
Explanation: Squamous cell carcinoma arises from keratinocytes in the stratum spinosum and is more likely to metastasize than basal cell carcinoma if left untreated.
Incorrect Answers:
A. Basal cells of the stratum basale – These are affected in basal cell carcinoma, not squamous cell carcinoma.
B. Melanocytes of the stratum basale – These give rise to melanoma, a different and more aggressive type of skin cancer.
D. Langerhans cells of the stratum lucidum – Langerhans cells are immune cells found mainly in the stratum spinosum, and stratum lucidum is found only in thick skin and does not contain these cells.
A thickened area of skin that arises due to constant abrasion is known as?
A. Cortex.
B. Bedsore.
C. Callus.
D. Catagen.
C. Callus.
Explanation: A callus is a thickened area of skin that develops in response to repeated friction or pressure, serving as a protective mechanism.
Incorrect Answers:
A. Cortex – The middle layer of the hair shaft, not related to skin thickening.
B. Bedsore – A pressure ulcer caused by prolonged pressure on the skin, not due to friction.
D. Catagen – A transitional phase in the hair growth cycle, unrelated to skin thickening.
