What is a key characteristic of apocrine glands compared to eccrine glands?
A) They are smaller than eccrine glands
B) They empty into hair follicles
C) They produce more sweat
D) They are found all over the body
E) They begin to function at birth
B) They empty into hair follicles
Explanation: Apocrine glands are larger than eccrine glands and specifically empty their ducts into hair follicles, particularly in areas like the armpit and genitals.
What type of sweat do apocrine glands produce?
A) Clear and odorless
B) Milky or yellowish in color
C) Salty and thin
D) Thick and sticky
E) Colorless and watery
B) Milky or yellowish in color
Explanation: Apocrine glands release a special kind of sweat that contains fatty acids and proteins, giving it a milky or yellowish color.
What is albinism?
A) A skin condition caused by sun exposure
B) A genetic disorder affecting melanin production
C) A type of skin cancer
D) An allergic reaction to skin products
E) A temporary skin condition from irritation
B) A genetic disorder affecting melanin production
Explanation: Albinism is a genetic disorder characterized by the inability of melanocytes to produce melanin, which affects the coloring of skin, hair, and nails.
What are nails primarily composed of?
A) Soft tissue
B) Collagen
C) Hard keratin
D) Muscle fibers
E) Bone
C) Hard keratin
Explanation: Nails are made of hard keratin, which consists of dead keratinized cells, providing strength and durability to the nail structure.
Where are sebaceous glands located in the body?
A) Only on the palms and soles
B) Over the entire body, except palms and soles
C) Only on the face
D) Only on the scalp
E) Only on the back
B) Over the entire body, except palms and soles
Explanation: Sebaceous glands are distributed throughout the body, but they are absent on the palms of the hands and the soles of the feet, highlighting their widespread presence.
At what stage of life do apocrine glands begin to function?
A) At birth
B) During childhood
C) At puberty
D) In old age
E) During adolescence
C) At puberty
Explanation: Apocrine glands begin to function at puberty, marking a significant change in sweat production and body odor.
What are sweat glands also known as?
A) Sebaceous glands
B) Sudoriferous glands
C) Exocrine glands
D) Endocrine glands
E) Apocrine glands
B) Sudoriferous glands
Explanation: Sweat glands are commonly referred to as sudoriferous glands, which is a term used to describe their function in producing sweat.
What is a key characteristic of vitiligo?
A) It causes excessive melanin production
B) It leads to a uniform skin tone
C) It results in patchy loss of skin color
D) It is caused by a bacterial infection
E) It affects only hair pigmentation
C) It results in patchy loss of skin color
Explanation: Vitiligo is characterized by the loss of color in patches due to the inability of melanocytes in certain areas to produce melanin, often linked to an autoimmune reaction.
What is the function of the arrector pili muscle?
A) To produce hair
B) To connect hair follicles to dermal tissue
C) To nourish hair follicles
D) To protect hair from damage
E) To change hair color
B) To connect hair follicles to dermal tissue
Explanation: The arrector pili muscle connects hair follicles to dermal tissue and causes hair to stand erect when it contracts, resulting in goosebumps.
Which part of the nail is referred to as the 'free edge'?
A) The part that grows from the nail matrix
B) The visible part of the nail that extends beyond the fingertip
C) The area beneath the nail
D) The root of the nail
E) The part that connects to the skin
B) The visible part of the nail that extends beyond the fingertip
Explanation: The 'free edge' of the nail is the portion that extends beyond the fingertip, making it the part of the nail that is most visible.
What type of glands are sebaceous glands?
A) Endocrine glands
B) Exocrine glands
C) Merocrine glands
D) Apocrine glands
E) Lymphatic glands
B) Exocrine glands
Explanation: Sebaceous glands are classified as exocrine glands because they secrete their product (sebum) through ducts onto the skin surface.
What is the primary function of the dermis layer of the skin?
A) Protection from UV rays
B) Sensation and thermoregulation
C) Storage of fat
D) Production of melanin
E) Absorption of nutrients
B) Sensation and thermoregulation
Explanation: The dermis is richly supplied with blood vessels and nerves, playing a crucial role in sensation and thermoregulation, making it essential for maintaining body temperature and responding to external stimuli.
What is the primary characteristic of the stratum spinosum?
A) It is the outermost layer of the epidermis
B) It has a spiny appearance due to histological preparation
C) It is completely devoid of cells
D) It contains only dead cells
E) It is the layer where hair follicles originate
B) It has a spiny appearance due to histological preparation
Explanation: The stratum spinosum is characterized by its spiny appearance, which is an artifact of histological preparation, indicating the presence of intercellular connections.
What is the primary role of apocrine glands in the body?
A) Temperature regulation
B) Producing hormones
C) Body odor production
D) Moisturizing the skin
E) Protecting against UV rays
C) Body odor production
Explanation: Apocrine glands play a minimal role in body temperature regulation but are primarily associated with the production of body odor due to the special sweat they release.
What is the primary function of eccrine glands?
A) To produce oil
B) To regulate body temperature
C) To secrete hormones
D) To provide moisture to the skin
E) To filter blood
B) To regulate body temperature
Explanation: The main function of eccrine glands is to help regulate body temperature through the production of sweat, which cools the body when it evaporates.
Which pigment is primarily responsible for the yellow, reddish brown, or black colors in skin?
A) Carotene
B) Hemoglobin
C) Melanin
D) Chlorophyll
E) Keratin
C) Melanin
Explanation: Melanin is the pigment that contributes to skin color, appearing in shades of yellow, reddish brown, or black, and is produced by melanocytes in the skin.
What causes the loss of pigmentation in vitiligo?
A) Genetic mutation
B) Autoimmune reaction
C) Environmental factors
D) Hormonal changes
E) Nutritional deficiencies
B) Autoimmune reaction
Explanation: The loss of pigmentation in vitiligo is believed to be caused by an autoimmune reaction where the body's immune system attacks melanocytes, leading to a loss of color in patches.
What is the hair bulb?
A) The outer layer of hair
B) The deep, expanded end of the hair follicle
C) The part of hair that is visible above the skin
D) The connective tissue surrounding the hair
E) The muscle that causes hair to stand up
B) The deep, expanded end of the hair follicle
Explanation: The hair bulb is the deep, expanded end of the hair follicle, where hair growth begins.
What is the most abundant cell type in the epidermis?
A) Merkel cells
B) Langerhans cells
C) Melanocytes
D) Keratinocytes
E) Fibroblasts
D) Keratinocytes
Explanation: Keratinocytes are the most abundant cell type in the epidermis, arising from the deepest layer and playing a crucial role in producing keratin, a tough fibrous protein that provides strength to the skin.
Where do nails grow from?
A) Nail bed
B) Nail matrix
C) Cuticle
D) Free edge
E) Nail root
B) Nail matrix
Explanation: Nails grow continuously from the nail matrix, which is the tissue located under the base of the nail, responsible for producing new nail cells.
What is the primary substance secreted by sebaceous glands?
A) Sweat
B) Sebum
C) Mucus
D) Hormones
E) Enzymes
B) Sebum
Explanation: Sebaceous glands secrete sebum, which is an oily substance that plays a crucial role in maintaining skin and hair health.
What are the two layers of the dermis?
A) Epidermal and Hypodermal
B) Papillary and Reticular
C) Superficial and Deep
D) Areolar and Dense
E) Outer and Inner
B) Papillary and Reticular
Explanation: The dermis consists of two layers: the papillary layer, which is superficial and made of areolar connective tissue, and the reticular layer, which is deeper and composed of dense irregular connective tissue.
Where is hair found on the human body?
A) Only on the head
B) Everywhere except palms, soles, lips, nipples, parts of the external genitalia, and distal segments of fingers and toes
C) Only on the arms and legs
D) Only on the face
E) Only on the back
B) Everywhere except palms, soles, lips, nipples, parts of the external genitalia, and distal segments of fingers and toes
Explanation: Hair is present on almost all parts of the human body, with specific exceptions noted, highlighting its widespread distribution.
What type of cells are primarily found in the stratum spinosum?
A) Keratinocytes
B) Melanocytes
C) Langerhans cells
D) Fibroblasts
E) Adipocytes
C) Langerhans cells
Explanation: The stratum spinosum contains star-shaped Langerhans cells, which are dendritic cells involved in immune response.
Where do the ducts of apocrine glands primarily empty?
A) Into the bloodstream
B) On the skin surface
C) Into hair follicles
D) Into sweat pores
E) Into sebaceous glands
C) Into hair follicles
Explanation: The ducts of apocrine glands empty into hair follicles, particularly in areas like the armpit and genitals, which is a distinguishing feature of these glands.
What is the deepest layer of the epidermis called?
A) Stratum corneum
B) Stratum granulosum
C) Stratum lucidum
D) Stratum basale
E) Stratum spinosum
D) Stratum basale
Explanation: The Stratum basale, also known as the Stratum Germinativum, is the deepest layer of the epidermis, where active cell division occurs.
Where are eccrine glands most numerous?
A) Only on the face
B) Only on the hands
C) Throughout the entire body
D) Only on the feet
E) Only in the armpits
C) Throughout the entire body
Explanation: Eccrine glands are the most numerous type of sweat glands and are found all over the body, including areas like the palms, soles, and forehead.
Where is the stratum lucidum found?
A) In all skin types
B) Only in thick skin (hands & soles)
C) Only in thin skin
D) In the dermis
E) In the hypodermis
B) Only in thick skin (hands & soles)
Explanation: The stratum lucidum is specifically noted to be present only in thick skin, such as the palms of the hands and the soles of the feet, highlighting its specialized function in these areas.
What is the source of carotene in the skin?
A) Blood cells
B) Sunlight
C) Some vegetables
D) Melanocytes
E) Dermal capillaries
C) Some vegetables
Explanation: Carotene is an orange-yellow pigment derived from certain vegetables and can be found in the skin, particularly in the palms and soles.
What is the primary purpose of the Rule of Nines in burn assessment?
A) To determine the type of burn
B) To estimate the total body surface area affected by burns
C) To calculate the pain level of burns
D) To identify the cause of burns
E) To assess the healing time for burns
B) To estimate the total body surface area affected by burns
Explanation: The Rule of Nines is primarily used to estimate the total body surface area (TBSA) affected by burns, which is crucial for determining treatment and fluid resuscitation needs.
Which of the following is NOT affected by albinism?
A) Skin color
B) Hair color
C) Nail color
D) Eye color
E) Muscle strength
E) Muscle strength
Explanation: Albinism affects the coloring of skin, hair, and nails, as well as eye color, but it does not impact muscle strength.
Which cells in the epidermis are associated with sensory nerve endings?
A) Keratinocytes
B) Langerhans cells
C) Merkel cells
D) Melanocytes
E) Fibroblasts
C) Merkel cells
Explanation: Merkel (or tactile) cells are associated with sensory nerve endings and are responsible for detecting light touch and pressure, primarily located at the dermo-epidermal junction.
What is alopecia areata?
A) A type of hair color
B) A disease that causes hair loss
C) A method of hair styling
D) A type of hair growth
E) A contagious infection
B) A disease that causes hair loss
Explanation: Alopecia areata is a disease where the body attacks its own hair follicles, leading to hair loss anywhere on the body. It is important to note that it is not contagious.
What characterizes a first degree burn?
A) Damage to the dermis
B) Damage only to the epidermis
C) Formation of blisters
D) Requires skin grafting
E) Extends to deeper tissues
B) Damage only to the epidermis
Explanation: A first degree burn affects only the epidermis, making it a superficial burn, commonly exemplified by sunburn.
What is the primary function of nails?
A) To provide insulation
B) To protect the tips of fingers and toes
C) To aid in sensation
D) To produce sweat
E) To absorb nutrients
B) To protect the tips of fingers and toes
Explanation: The primary function of nails is to protect the sensitive tips of fingers and toes, enhancing the ability to grasp and manipulate objects.
What type of secretion do sebaceous glands use?
A) Merocrine secretion
B) Apocrine secretion
C) Holocrine secretion
D) Endocrine secretion
E) Exocrine secretion
C) Holocrine secretion
Explanation: Sebaceous glands utilize holocrine secretion, where the entire cell disintegrates to release its contents, including sebum.
What is the role of dermal papillae?
A) To produce sweat
B) To provide nutrients to the epidermis
C) To form fingerprints
D) To regulate temperature
E) To sense light touch
C) To form fingerprints
Explanation: Dermal papillae, found in the papillary layer of the dermis, create the epidermal ridges that leave fingerprints on hands and feet, contributing to individual identification.
Which type of gland is responsible for producing oil in the skin?
A) Sweat glands
B) Mammary glands
C) Sebaceous or oil glands
D) Salivary glands
E) Thyroid glands
C) Sebaceous or oil glands
Explanation: Sebaceous glands, also known as oil glands, are responsible for producing oil that helps to lubricate and protect the skin.
What is the main function of keratohyaline granules found in the stratum granulosum?
A) To provide color to the skin
B) To help form keratin
C) To absorb UV radiation
D) To produce melanin
E) To facilitate cell division
B) To help form keratin
Explanation: Keratohyaline granules in the stratum granulosum play a crucial role in the formation of keratin, which is essential for the protective function of the skin.
What type of cells are primarily formed in the Stratum basale?
A) Melanocytes
B) Merkel cells
C) Keratinocytes
D) Fibroblasts
E) Adipocytes
C) Keratinocytes
Explanation: The Stratum basale contains stem cells that undergo mitosis to form keratinocytes, which are essential for the formation of the more superficial layers of the epidermis.
What is the composition of sweat produced by eccrine glands?
A) 50% water, 50% salts
B) 99% water, salts, vitamin C, and traces of metabolic waste
C) 100% oil
D) 75% alcohol, 25% water
E) 90% sugar, 10% water
B) 99% water, salts, vitamin C, and traces of metabolic waste
Explanation: The sweat produced by eccrine glands is primarily composed of 99% water, along with salts, vitamin C, and traces of metabolic waste, making it an effective means of thermoregulation.
What is the primary composition of the stratum lucidum?
A) Living keratinocytes
B) A few rows of flat, dead keratinocytes
C) Melanocytes
D) Collagen fibers
E) Sweat glands
B) A few rows of flat, dead keratinocytes
Explanation: The stratum lucidum is composed of a few rows of flat, dead keratinocytes, which contribute to its clear appearance and protective function in thick skin.
What is the primary structure of hair?
A) Muscle
B) Bone
C) Keratinized epithelial structure
D) Connective tissue
E) Nervous tissue
C) Keratinized epithelial structure
Explanation: Hair is described as a flexible type of dead, keratinized epithelial structure, highlighting its composition and nature.
What role does hemoglobin play in skin color?
A) It provides a yellow tint
B) It is responsible for the red coloring from blood cells
C) It determines skin transparency
D) It is a precursor of Vitamin A
E) It absorbs UV radiation
B) It is responsible for the red coloring from blood cells
Explanation: Hemoglobin gives skin its red coloring due to the blood cells in dermal capillaries, and the oxygen content in the blood affects the intensity of this red color.
In the Rule of Nines, what percentage is assigned to the entire head and neck?
A) 9%
B) 18%
C) 4.5%
D) 12%
E) 27%
A) 9%
Explanation: According to the Rule of Nines, the entire head and neck account for 9% of the total body surface area, which helps in quick assessments of burn severity.
What is the primary function of Langerhans cells in the epidermis?
A) Produce keratin
B) Detect light touch
C) Produce melanin
D) Act as phagocytic cells
E) Provide structural support
D) Act as phagocytic cells
Explanation: Langerhans (or dendritic) cells are phagocytic cells found in the stratum spinosum and play a vital role in the immune system by capturing and presenting antigens.
What is the role of the root plexus?
A) To produce hair
B) To provide nourishment to hair
C) To sense movement around the hair bulb
D) To connect hair to the skin
E) To protect hair from UV rays
C) To sense movement around the hair bulb
Explanation: The root plexus is a knot of sensory nerves around the hair bulb that helps detect movement and sensations, contributing to the sensory function of hair.
What is a key feature of a second degree burn?
A) It affects only the epidermis
B) It consumes all thickness of skin
C) Blisters appear
D) It requires immediate skin grafting
E) It extends to deeper tissues
C) Blisters appear
Explanation: A second degree burn damages the upper part of the dermis and is characterized by the appearance of blisters, while healing typically occurs with little scarring.
Which of the following is NOT a part of the nail?
A) Free edge
B) Body
C) Root
D) Nail matrix
E) Nail bed
E) Nail bed
Explanation: While the nail bed is an important structure related to nails, it is not classified as a part of the nail itself. The main parts of the nail include the free edge, body, and root.
What type of connective tissue primarily makes up the reticular layer of the dermis?
A) Loose areolar connective tissue
B) Dense irregular connective tissue
C) Adipose tissue
D) Cartilage
E) Stratified squamous epithelium
B) Dense irregular connective tissue
Explanation: The reticular layer of the dermis is primarily composed of dense irregular connective tissue, which provides strength and elasticity to the skin.
What is one of the main functions of sebum?
A) To cool the skin
B) To soften and lubricate hair and skin
C) To promote sweating
D) To absorb UV radiation
E) To produce vitamin D
B) To soften and lubricate hair and skin
Explanation: One of the primary functions of sebum is to soften and lubricate both hair and skin, which helps prevent bacterial infections and maintains skin integrity.
What is the primary function of sweat glands?
A) To produce oil
B) To regulate body temperature and excrete waste
C) To produce milk
D) To provide structural support
E) To protect against UV radiation
B) To regulate body temperature and excrete waste
Explanation: Sweat glands play a crucial role in thermoregulation and waste excretion through the secretion of sweat.
Which cells are found in the Stratum basale besides keratinocytes?
A) Osteocytes
B) Merkel cells and Melanocytes
C) Chondrocytes
D) Erythrocytes
E) Neurons
B) Merkel cells and Melanocytes
Explanation: In addition to keratinocytes, the Stratum basale contains Merkel cells (tactile cells) and Melanocytes, which are involved in sensation and pigmentation, respectively.
What does redness (erythema) of the skin indicate?
A) Liver disorder
B) Emotional stress
C) Impaired blood flow
D) Embarrassment or inflammation
E) Low blood pressure
D) Embarrassment or inflammation
Explanation: Redness, or erythema, can occur due to various factors including embarrassment, inflammation, hypertension, fever, or allergy, indicating increased blood flow to the skin.
What do lamellated granules in the stratum granulosum contain?
A) Melanin
B) Keratin
C) A waterproofing glycolipid
D) Collagen fibers
E) Nutrients for cell growth
C) A waterproofing glycolipid
Explanation: Lamellated granules contain a waterproofing glycolipid that helps to prevent water loss from the skin, contributing to its barrier function.
How do eccrine glands release sweat?
A) Through hair follicles
B) Via ducts to sweat pores on the skin’s surface
C) Directly into the bloodstream
D) Through the sebaceous glands
E) By evaporation only
B) Via ducts to sweat pores on the skin’s surface
Explanation: Eccrine glands open via ducts that lead to sweat pores on the skin's surface, allowing sweat to be released and perform its cooling function.
What is the largest organ of the human body?
A) Heart
B) Liver
C) Skin
D) Lungs
E) Brain
C) Skin
Explanation: The skin, also known as the integument, is the largest organ of the human body, accounting for approximately 7% of body weight.
What is the main function of the stratum corneum?
A) To produce melanin
B) To provide sensation
C) To protect against dehydration, abrasion, and microbial penetration
D) To facilitate nutrient absorption
E) To regulate temperature
C) To protect against dehydration, abrasion, and microbial penetration
Explanation: The stratum corneum serves as a thick layer of dead keratinocytes that protects the skin from dehydration, abrasion, and penetration by microbes, making it a crucial barrier in the epidermis.
What part of the hair is embedded in the skin?
A) Shaft
B) Medulla
C) Cuticle
D) Root
E) Cortex
D) Root
Explanation: The root of the hair is the part that is embedded in the skin and enclosed in a sheath known as the hair follicle.
What is the primary function of the epidermis?
A) To provide insulation
B) To protect against environmental damage
C) To store fat
D) To produce sweat
E) To support blood vessels
B) To protect against environmental damage
Explanation: The epidermis serves as the outermost layer of skin, primarily functioning to protect the body from environmental damage such as pathogens, UV radiation, and physical abrasions.
How much of the total body surface area does each arm represent in the Rule of Nines?
A) 4.5%
B) 9%
C) 18%
D) 12%
E) 27%
B) 9%
Explanation: Each arm is assigned 9% of the total body surface area in the Rule of Nines, which aids in estimating the extent of burns on a patient's body.
What causes the redness observed in the skin of Caucasians?
A) High levels of carotene
B) Melanin concentration
C) Blood vessels filled with red blood cells
D) Lack of hemoglobin
E) Excessive UV exposure
C) Blood vessels filled with red blood cells
Explanation: The redness in the skin of Caucasians is attributed to the transparency of their skin, which allows the color of blood vessels filled with red blood cells (hemoglobin) to be visible.
What pigment do melanocytes produce?
A) Keratin
B) Hemoglobin
C) Melanin
D) Collagen
E) Elastin
C) Melanin
Explanation: Melanocytes are responsible for producing the pigment melanin, which contributes to skin color and provides protection against UV radiation. They are primarily located in the stratum basale.
Which layers make up the epithelial root sheath of the hair follicle?
A) Only the internal layer
B) Only the external layer
C) Both internal and external layers
D) The connective tissue layer
E) The arrector pili muscle
C) Both internal and external layers
Explanation: The epithelial root sheath of the hair follicle consists of both internal and external layers, providing structure and support to the hair follicle.
What distinguishes a third degree burn?
A) It only affects the epidermis
B) It causes blisters
C) It consumes all thickness of skin
D) It heals without scarring
E) It is a superficial burn
C) It consumes all thickness of skin
Explanation: A third degree burn involves complete destruction of both the epidermis and dermis, resulting in a burned area that may appear white, red, or blackened, and it typically requires skin grafting for healing.
What are lamellar corpuscles responsible for?
A) Sensing temperature
B) Detecting deep pressure and vibration
C) Producing sweat
D) Forming hair follicles
E) Regulating blood flow
B) Detecting deep pressure and vibration
Explanation: Lamellar corpuscles, located in the dermis, are specialized receptors that detect deep pressure, vibration, and proprioception, contributing to the sensory functions of the skin.
Which of the following is NOT an accessory skin structure?
A) Hair
B) Nails
C) Sebaceous glands
D) Epidermis
E) Sweat glands
D) Epidermis
Explanation: The epidermis is a layer of skin, while hair, nails, sebaceous glands, and sweat glands are considered accessory structures or appendages of the skin.
What is the primary function of the Stratum basale?
A) Protection from UV radiation
B) Cell division and regeneration
C) Sensation
D) Waterproofing the skin
E) Producing sweat
B) Cell division and regeneration
Explanation: The Stratum basale serves as the mitotic layer of the epidermis, where cells actively divide to regenerate the skin and form the upper layers.
What condition is indicated by pallor (blanching) of the skin?
A) Fever
B) Bruising
C) Liver disorder
D) Emotional stress or anaemia
E) High blood pressure
D) Emotional stress or anaemia
Explanation: Pallor, or blanching, can result from emotional stress such as fear, anaemia, low blood pressure, or impaired blood flow, reflecting a decrease in blood supply to the skin.
Which layer of the epidermis is known for some mitosis occurring in its deeper layer?
A) Stratum corneum
B) Stratum lucidum
C) Stratum granulosum
D) Stratum spinosum
E) Stratum basale
D) Stratum spinosum
Explanation: The stratum spinosum is noted for some mitosis occurring in its deeper layer, contributing to the regeneration of the epidermis.
What percentage of body weight does the skin account for?
A) 5%
B) 10%
C) 7%
D) 15%
E) 20%
C) 7%
Explanation: The skin accounts for about 7% of the total body weight, highlighting its significant mass in the human body.
What characterizes the stratum corneum?
A) It is the only living layer of the epidermis
B) It contains a high concentration of melanocytes
C) It has thickened plasma membranes and is composed of dead keratinocytes
D) It is the deepest layer of the epidermis
E) It is primarily made of collagen
C) It has thickened plasma membranes and is composed of dead keratinocytes
Explanation: The stratum corneum is characterized by its thick layer of dead keratinocytes and thickened plasma membranes, which enhance its protective functions.
Which layer of hair surrounds the medulla?
A) Cuticle
B) Cortex
C) Root
D) Shaft
E) Follicle
B) Cortex
Explanation: The cortex is the layer that surrounds the medulla, providing strength and color to the hair.
What percentage of the total body surface area is assigned to the anterior trunk in the Rule of Nines?
A) 18%
B) 9%
C) 27%
D) 12%
E) 36%
A) 18%
Explanation: The anterior trunk is assigned 18% of the total body surface area in the Rule of Nines, which is important for assessing burn injuries.
Which layer of skin contains blood vessels and nerves?
A) Epidermis
B) Hypodermis
C) Dermis
D) Stratum corneum
E) Stratum basale
C) Dermis
Explanation: The dermis is the layer of skin that contains blood vessels, nerves, and connective tissue, providing structural support and nourishment to the epidermis above it.
Which pigment is a precursor of Vitamin A?
A) Melanin
B) Hemoglobin
C) Carotene
D) Chlorophyll
E) Keratin
C) Carotene
Explanation: Carotene is an orange-yellow pigment that serves as a precursor to Vitamin A, which is essential for various bodily functions.
What are the main components of the integumentary system?
A) Muscles and bones
B) Skin and accessory structures
C) Organs and tissues
D) Blood and lymph
E) Nerves and neurons
B) Skin and accessory structures
Explanation: The integumentary system primarily consists of the skin and its accessory structures, which include skin appendages such as hair and nails.
Where are melanocytes primarily located in the epidermis?
A) Stratum corneum
B) Stratum granulosum
C) Stratum spinosum
D) Stratum basale
E) Stratum lucidum
D) Stratum basale
Explanation: Melanocytes are primarily found in the stratum basale of the epidermis, where they produce melanin and contribute to the skin's pigmentation.
What type of skin neoplasm is most common in humans?
A) Basal cell carcinoma
B) Squamous cell carcinoma
C) Malignant melanoma
D) Warts
E) Lipoma
A) Basal cell carcinoma
Explanation: Basal cell carcinoma is noted as the most common type of skin cancer in humans, although it is the least malignant among skin neoplasms.
Which of the following is true about fourth degree burns?
A) They only affect the epidermis
B) They heal without scarring
C) They extend to deeper tissues
D) They are superficial burns
E) They only affect the upper dermis
C) They extend to deeper tissues
Explanation: Fourth degree burns are full thickness burns that not only damage the skin but also extend into deeper tissues, making them the most severe type of burn.
What type of glands are mammary glands classified as?
A) Sebaceous glands
B) Sweat glands
C) Endocrine glands
D) Exocrine glands
E) Lymphatic glands
D) Exocrine glands
Explanation: Mammary glands are classified as exocrine glands because they secrete milk through ducts to the surface, distinguishing them from endocrine glands that release hormones directly into the bloodstream.
What does jaundice indicate?
A) High blood pressure
B) Liver disorder
C) Emotional stress
D) Inflammation
E) Bruising
B) Liver disorder
Explanation: Jaundice, characterized by a yellow cast to the skin, typically indicates a liver disorder, as it results from the accumulation of bilirubin in the blood.
What is the relationship between the Stratum basale and the dermis?
A) They are completely separate
B) The Stratum basale is attached to the underlying dermis
C) The dermis is above the Stratum basale
D) The Stratum basale is thicker than the dermis
E) They are both part of the same layer
B) The Stratum basale is attached to the underlying dermis
Explanation: The Stratum basale is the deepest layer of the epidermis and is attached to the underlying dermis, providing structural support and nourishment.
Into how many distinct layers is the skin divided?
A) One
B) Two
C) Three
D) Four
E) Five
B) Two
Explanation: The skin is divided into two distinct layers: the epidermis and the dermis, which serve different functions and have different structures.
What is the outermost layer of hair called?
A) Medulla
B) Cortex
C) Follicle
D) Cuticle
E) Shaft
D) Cuticle
Explanation: The cuticle is the outermost layer of hair, serving as a protective barrier for the inner layers.
Which body part is assigned 18% of the total body surface area in the Rule of Nines?
A) Each leg
B) Each arm
C) The back
D) The head
E) The abdomen
A) Each leg
Explanation: Each leg is assigned 18% of the total body surface area in the Rule of Nines, which is essential for evaluating the severity of burns and planning treatment.
What type of cells primarily make up the epidermis?
A) Adipocytes
B) Keratinocytes
C) Fibroblasts
D) Melanocytes
E) Chondrocytes
B) Keratinocytes
Explanation: The epidermis is primarily composed of keratinocytes, which are responsible for producing keratin, a protein that helps protect the skin and underlying tissues.
Which function of the integumentary system is associated with sensory receptors?
A) Protection
B) Temperature regulation
C) Vitamin D production
D) Excretion
E) Sensation
E) Sensation
Explanation: The integumentary system plays a crucial role in sensation, containing sensory receptors for pain and touch that are linked to nerve endings.
Which skin cancer arises from cells of the stratum spinosum?
A) Basal cell carcinoma
B) Malignant melanoma
C) Warts
D) Squamous cell carcinoma
E) Keratoacanthoma
D) Squamous cell carcinoma
Explanation: Squamous cell carcinoma arises from the cells of the stratum spinosum and is associated with UV exposure as an important risk factor.
How do first and second degree burns differ in terms of healing?
A) Both require skin grafting
B) Both heal with significant scarring
C) Both can regenerate without scarring
D) Only first degree burns heal quickly
E) Only second degree burns heal with scarring
C) Both can regenerate without scarring
Explanation: Both first and second degree burns can heal with little to no scarring, as regeneration is possible for these types of burns.
What are bruises (black and blue marks) a result of?
A) High blood pressure
B) Liver disorder
C) Hematomas
D) Emotional stress
E) Inflammation
C) Hematomas
Explanation: Bruises, or black and blue marks, are caused by hematomas, which occur when blood vessels are damaged and blood leaks into the surrounding tissues.
What lies deep to the dermis?
A) Epidermis
B) Hypodermis
C) Subcutaneous layer
D) Muscle tissue
E) Fat tissue
B) Hypodermis
Explanation: The hypodermis, also known as the subcutaneous layer, lies deep to the dermis and plays a role in insulation and cushioning.
What are the three concentric layers of keratinized cells in hair?
A) Root, Shaft, Follicle
B) Medulla, Cortex, Cuticle
C) Hair, Skin, Follicle
D) Follicle, Shaft, Cuticle
E) Medulla, Root, Shaft
B) Medulla, Cortex, Cuticle
Explanation: The three concentric layers of keratinized cells in hair are the medulla (central core), cortex (surrounds the medulla), and cuticle (outermost layer).
Which layer of skin is responsible for the sensation of touch?
A) Epidermis
B) Hypodermis
C) Dermis
D) Stratum lucidum
E) Stratum granulosum
C) Dermis
Explanation: The dermis contains various sensory receptors that are responsible for the sensation of touch, pressure, and pain, making it crucial for the skin's sensory functions.
How does the integumentary system help regulate body temperature?
A) By producing hormones
B) Through sweat glands and a rich capillary network
C) By increasing heart rate
D) Through muscle contractions
E) By altering blood pressure
B) Through sweat glands and a rich capillary network
Explanation: Temperature regulation in the integumentary system is achieved through the action of sweat glands and the extensive network of capillaries in the skin, which help dissipate heat.
What is a significant risk factor for developing squamous cell carcinoma?
A) Genetic predisposition
B) UV exposure
C) Viral infections
D) Aging
E) Poor nutrition
B) UV exposure
Explanation: UV exposure is highlighted as an important risk factor for the development of squamous cell carcinoma, emphasizing the role of sun exposure in skin cancer risk.
Which of the following is NOT a layer of the skin?
A) Epidermis
B) Dermis
C) Hypodermis
D) Subcutaneous layer
E) Endodermis
E) Endodermis
Explanation: The endodermis is not a layer of the skin; the skin consists of the epidermis, dermis, and hypodermis (or subcutaneous layer).
What is the role of melanocytes in the epidermis?
A) To produce collagen
B) To store fat
C) To produce melanin
D) To facilitate healing
E) To regulate temperature
C) To produce melanin
Explanation: Melanocytes are specialized cells in the epidermis that produce melanin, the pigment responsible for skin color and protection against UV radiation.
What role does the integumentary system play in vitamin D production?
A) It stores vitamin D
B) It produces vitamin D when exposed to sunlight
C) It transports vitamin D to other organs
D) It breaks down vitamin D
E) It regulates vitamin D levels in the blood
B) It produces vitamin D when exposed to sunlight
Explanation: The integumentary system is responsible for the production of vitamin D when the skin is exposed to sunlight, which is essential for various bodily functions.
Which type of skin neoplasm is highly malignant and arises from melanocytes?
A) Basal cell carcinoma
B) Squamous cell carcinoma
C) Malignant melanoma
D) Warts
E) Fibroma
C) Malignant melanoma
Explanation: Malignant melanoma is characterized as highly malignant and arises from melanocytes, often due to accumulated DNA damage in skin cells.
What substances are excreted through the integumentary system?
A) Nutrients and vitamins
B) Salts and wastes (ammonia & urea)
C) Hormones and enzymes
D) Oxygen and carbon dioxide
E) Proteins and carbohydrates
B) Salts and wastes (ammonia & urea)
Explanation: The integumentary system facilitates the excretion of salts and metabolic wastes such as ammonia and urea through the process of sweating.
What virus is associated with the formation of warts?
A) Herpes simplex virus
B) Human papillomavirus (HPV)
C) Varicella-zoster virus
D) Hepatitis B virus
E) Cytomegalovirus
B) Human papillomavirus (HPV)
Explanation: Warts are benign skin neoplasms that are specifically associated with the human papillomavirus (HPV), which is responsible for their development.
