1.
This is another name for the subcutaneous layer.
Correct Answer
E. Hypodermis
Explanation
The hypodermis is also known as the subcutaneous layer. It is the deepest layer of the skin and is located below the dermis. The hypodermis is composed of fat cells and connective tissue, which helps to insulate the body and provide cushioning. It also contains blood vessels and nerves that supply the skin.
2.
This layer is composed of keratinized stratified squamous epithelium.
Correct Answer
A. Epidermis
Explanation
The correct answer is Epidermis because it is the outermost layer of the skin and is composed of keratinized stratified squamous epithelium. This layer provides a protective barrier for the underlying tissues and helps to regulate body temperature. The epidermis also contains melanocytes, which produce melanin, the pigment responsible for skin color.
3.
Keratin
Correct Answer
A. Is a protein
Explanation
The correct answer is "Is a protein." Keratin is a type of protein that is found in the outer layer of the skin, hair, and nails. It provides strength and protection to these structures.
4.
This pigment absorbs ultraviolet light.
Correct Answer
B. Melanin
Explanation
Melanin is a pigment that is responsible for the color of our skin, hair, and eyes. It acts as a natural sunscreen by absorbing ultraviolet (UV) light from the sun, preventing it from damaging our DNA and causing sunburns or skin cancer. Melanin production increases when exposed to sunlight, resulting in a tan. Therefore, melanin is the correct answer as it absorbs ultraviolet light.
5.
This epidermal cell has a role in immunity and disease resistance.
Correct Answer
A. Langerhans
Explanation
Langerhans cells are a type of epidermal cell that play a crucial role in the immune system and disease resistance. They are responsible for capturing and presenting antigens to activate the immune response. Langerhans cells are found in the skin and mucous membranes, acting as a first line of defense against pathogens. Their ability to recognize and respond to foreign substances makes them essential in protecting the body from infections and diseases.
6.
This layer of epidermis is composed of a single row of cuboidal or columnar keratinocytes.
Correct Answer
A. Stratum basale
Explanation
The stratum basale is the correct answer because it is the layer of the epidermis that is composed of a single row of cuboidal or columnar keratinocytes. This layer is responsible for cell division and the production of new skin cells. It is also the layer where melanocytes are found, which produce melanin, the pigment responsible for skin color.
7.
This layer of the epidermis contains layers of flattened keratinocytes that are going through apoptosis.
Correct Answer
C. Stratum granulosum
Explanation
The stratum granulosum is the correct answer because it is the layer of the epidermis where keratinocytes undergo apoptosis, or programmed cell death. This layer contains flattened keratinocytes that are filled with granules of keratin, which is a protein that provides structural support to the skin. As the keratinocytes move up through the layers of the epidermis, they gradually flatten and lose their nuclei, ultimately undergoing apoptosis in the stratum granulosum.
8.
The stratum lucidum
Correct Answer
D. Is present only in thick skin
Explanation
The stratum lucidum is a layer of the epidermis that is only present in thick skin. Thick skin is found in areas of the body that undergo a lot of friction and pressure, such as the palms of the hands and the soles of the feet. This layer is not present in thin skin, which covers the rest of the body. The stratum lucidum consists of 25-30 layers of dead keratinocytes and is located just superficially to the stratum basale. It does not contain lamellar granules. Skin grafts typically involve taking a thin layer of skin from one area of the body and transplanting it to another area that has been damaged or lost skin. The stratum lucidum is not specifically used in skin grafts.
9.
Constant exposure of skin to friction stimulates the formation of a callus which is the thickening of which layer?
Correct Answer
E. Stratum corneum
Explanation
Constant exposure of skin to friction stimulates the formation of a callus, which is the thickening of the outermost layer of the epidermis called the stratum corneum. This layer is composed of dead skin cells that have been flattened and hardened, providing a protective barrier for the underlying layers of the skin. The constant friction leads to an increased production of these cells, resulting in the formation of a callus.
10.
Keratinization
Correct Answer
B. Is the process of cells accumlating keratin
Explanation
Keratinization is the process in which cells accumulate keratin. Keratin is a tough, fibrous protein that is the main structural component of hair, nails, and the outer layer of skin. During keratinization, the cells in the outer layer of the skin, called the epidermis, undergo a process of maturation and become filled with keratin. This process helps to create a protective barrier for the skin and gives it strength and durability. Keratinization is not involved in synthesizing pigment in the skin, and it is not limited to thin skin only.
11.
This layer is composed mainly of connective tissue with collagen and elastic fibres.
Correct Answer
D. Dermis
Explanation
The dermis is the layer of skin that is composed mainly of connective tissue with collagen and elastic fibers. It is located between the epidermis (outermost layer of skin) and the subcutaneous layer. The dermis provides structural support to the skin, as well as elasticity and strength due to the presence of collagen and elastic fibers. It also contains blood vessels, nerves, hair follicles, sweat glands, and sebaceous glands.
12.
Albinism
Correct Answer
A. Is the absence of melanin
Explanation
Albinism is a genetic condition characterized by the absence of melanin, the pigment responsible for the color of the skin, hair, and eyes. People with albinism often have very light or white hair, skin, and eyes due to the lack of melanin production. This condition can also cause vision problems, as melanin is important for the development and function of the eyes. Therefore, the correct answer is that albinism is the absence of melanin.
13.
Thick skin
Correct Answer
E. All of the above
Explanation
The correct answer is "All of the above." Thick skin is found in specific areas of the body such as the palms, soles of the feet, and fingertips. It does not contain hair follicles and has more sweat glands compared to thin skin. Additionally, thick skin contains epidermal ridges.
14.
Which of the following plays an important role in thermoregulation?
Correct Answer
C. Sweat gland
Explanation
The sweat gland plays an important role in thermoregulation. When the body temperature rises, the sweat glands produce sweat, which is then evaporated from the skin surface, cooling down the body. This process helps to regulate body temperature and prevent overheating.
15.
This skin structure acts to prevent water loss as well as inhibiting bacterial growth on the surface of the skin.
Correct Answer
E. Oil glands
Explanation
Oil glands, also known as sebaceous glands, produce sebum, an oily substance that helps to moisturize and lubricate the skin. Sebum forms a protective barrier on the skin's surface, preventing excessive water loss and keeping the skin hydrated. Additionally, sebum has antimicrobial properties that inhibit the growth of bacteria on the skin, reducing the risk of infections. Therefore, oil glands play a crucial role in preventing water loss and inhibiting bacterial growth on the skin's surface.
16.
This is fine nonpigmented hair that covers the body of the fetus.
Correct Answer
C. Lanugo
Explanation
Lanugo refers to the fine nonpigmented hair that covers the body of a fetus. It is a temporary type of hair that is typically shed before birth. This hair serves to keep the fetus warm and protect its delicate skin. After birth, lanugo is usually replaced by vellus hair, which is finer and less pigmented. Alopecia refers to hair loss, and hair follicles are the structures in the skin from which hair grows.
17.
This type of gland is a branched acinar gland connected to a hair follicle.
Correct Answer
A. Sebaceous
Explanation
Sebaceous glands are branched acinar glands that are connected to hair follicles. These glands produce sebum, an oily substance that helps lubricate the skin and hair. Sebaceous glands are most commonly found on the face, scalp, and upper body. They play a crucial role in maintaining the health and hydration of the skin and hair.
18.
This is a mixture of triglycerides, cholesterol, proteins and inorganic salts.
Correct Answer
D. Sebum
Explanation
Sebum is a mixture of triglycerides, cholesterol, proteins, and inorganic salts. It is produced by the sebaceous glands in the skin. Sebum helps to lubricate the skin and hair, keeping them moisturized and preventing them from drying out. It also has antimicrobial properties, protecting the skin from harmful bacteria. Sebum can sometimes become overproduced, leading to oily skin or acne.
19.
This type of gland is a coiled tubular gland found almost throughout the entirety of the skin.
Correct Answer
B. Eccrine
Explanation
Eccrine glands are coiled tubular glands that are found almost throughout the entirety of the skin. These glands are responsible for producing sweat, which helps regulate body temperature. They are most abundant on the palms of the hands, soles of the feet, and forehead. Sebaceous glands, on the other hand, produce sebum, which is an oily substance that lubricates the skin and hair. Apocrine glands are found in specific areas such as the armpits and groin, and they produce a thicker sweat that can be broken down by bacteria, resulting in body odor. Ceruminous glands are found in the ear canal and produce earwax.
20.
What is the function of skin?
Correct Answer
E. All of the above
Explanation
The skin serves multiple functions. It helps regulate body temperature through thermoregulation, protecting the body from external elements and injuries. The skin also plays a role in secretion and absorption processes, allowing substances to be released or absorbed. Additionally, it is involved in the synthesis of vitamin D when exposed to sunlight. Therefore, all of the given options are correct as they represent different functions of the skin.
21.
What are the steps in epidermal wound healing?
Correct Answer
A. Epidermal injury - basal cells break contact with the basement membrane - basal cells enlarge and migrate across the wound - contact inhibition
Explanation
Epidermal wound healing begins with an epidermal injury. The basal cells, which are located at the bottom layer of the epidermis, break contact with the basement membrane. After that, these basal cells enlarge and migrate across the wound. Finally, contact inhibition occurs, which means that the basal cells stop migrating once they come into contact with each other. This sequence of events allows for the regeneration and repair of the epidermal tissue.
22.
What happens in the maturation phase of a deep wound healing?
Correct Answer
E. All of the above
Explanation
In the maturation phase of deep wound healing, several processes occur. The scab, which is formed during the earlier stages of healing, sloughs off as the wound continues to heal. Collagen fibers, which are responsible for providing strength and structure to the wound, become more organized during this phase. Fibroblasts, which are cells that play a crucial role in wound healing, decrease in number as the healing progresses. Additionally, blood vessels are restored to their normal state during this phase. Therefore, all of the above statements are true for the maturation phase of deep wound healing.
23.
What are the steps in deep wound healing?
Correct Answer
B. Wound formation - inflammation - migratory pHase - maturation pHase
Explanation
The correct answer is "Wound formation - inflammation - migratory phase - maturation phase". This sequence accurately represents the steps in deep wound healing. Wound formation is the initial step where the injury occurs. Inflammation follows, which involves the body's immune response to remove debris and pathogens from the wound. The migratory phase comes next, where cells move into the wound to start the repair process. Finally, the maturation phase occurs, where the newly formed tissue remodels and strengthens over time.
24.
In this type of scarring, the scar tissue extends beyond the boundary of the injury into normal tissue.
Correct Answer
B. Keloid
Explanation
Keloid is the correct answer because it is a type of scarring where the scar tissue extends beyond the boundary of the injury into normal tissue. Unlike hypertrophic scars, which stay within the boundaries of the original wound, keloids can grow larger and spread beyond the initial injury site. This excessive growth of scar tissue is often raised, thick, and can be itchy or painful. Keloids can occur after any type of injury, such as surgery, burns, or even minor skin trauma. They are more common in individuals with darker skin tones and may require medical treatment to manage their growth.
25.
In the diagram, where is the sebaceous gland?
Correct Answer
A. C
Explanation
The sebaceous gland is located in the dermis layer of the skin. In the given diagram, option C represents the dermis layer, which is where the sebaceous gland is located. Therefore, option C is the correct answer.
26.
In the diagram, where is the apocrine sweat gland?
Correct Answer
D. F
Explanation
The apocrine sweat gland is located at position F in the diagram.
27.
In the diagram, where are the rideges that serve as fingerprints?
Correct Answer
A. A
Explanation
The correct answer is A because in the diagram, only A has the ridges that serve as fingerprints. B, G, and H do not have any ridges, and "None of the above" is not a valid option as A is the correct answer.
28.
In the diagram, where is the reticular region of the dermis?
Correct Answer
D. H
Explanation
The reticular region of the dermis is located in area H of the diagram.
29.
In the diagram, where is the arrector pili muscle?
Correct Answer
B. D
Explanation
The arrector pili muscle is located in the dermis layer of the skin and is responsible for causing hair to stand up or "goosebumps" when it contracts. In the diagram, option D is the correct answer as it is the only location labeled as the arrector pili muscle.
30.
In the photo, which layer is the stratum spinosum?
Correct Answer
D. D
31.
In the photo, which layer is only seen in thick skin?
Correct Answer
B. B
Explanation
The correct answer is B. In thick skin, the layer that is only seen is the stratum lucidum. This layer is located between the stratum granulosum and the stratum corneum. It is characterized by its translucent appearance and is only present in areas of the body with thick skin, such as the palms of the hands and soles of the feet.
32.
In the photo, which layer is the stratum basale?
Correct Answer
D. E
Explanation
The deepest layer, known as stratum basale or stratum germinativum, is separated from the dermis by the basement membrane (basal lamina) and connected to it through hemidesmosomes.
33.
In the diagram, where is the cortex?
Correct Answer
A. B
Explanation
The cortex is located at position B in the diagram.
34.
In the diagram, where is the dermal root sheath?
Correct Answer
D. F
Explanation
The dermal root sheath is located at position F in the diagram.
35.
In the diagram, where is the cuticle of the hair?
Correct Answer
C. C
Explanation
The cuticle of the hair is located at position C in the diagram. The cuticle is the outermost layer of the hair shaft and acts as a protective barrier. It consists of overlapping scales that help to protect the inner layers of the hair from damage and moisture loss.
36.
In the figure, where is the eponychium?
Correct Answer
B. B
Explanation
The eponychium is located at the base of the nail, where the nail and the skin meet. In the given figure, option B is the only location that matches this description. Therefore, option B is where the eponychium is located.
37.
In the figure, where is the hyponychium?
Correct Answer
E. G
Explanation
The hyponychium is located at the distal end of the nail bed, where the nail plate extends beyond the fingertip. In the given figure, G represents the distal end of the nail bed, making it the correct location for the hyponychium.
38.
In the figure, where is the nail root?
Correct Answer
A. A
Explanation
The nail root is located at the base of the nail, where it is attached to the skin. This is the area where the nail grows from and is responsible for producing new cells that make up the nail plate. Therefore, option A is the correct answer as it represents the location of the nail root.
39.
In the figure, where is the nail matrix?
Correct Answer
C. E
Explanation
The nail matrix is located at the base of the nail, underneath the cuticle. It is responsible for producing new nail cells, which then push the older cells forward to form the visible part of the nail. Therefore, option E is the correct answer as it represents the location of the nail matrix in the figure.
40.
In the figure, where is hte lunula?
Correct Answer
C. C
Explanation
The lunula is the white, crescent-shaped area located at the base of the nail. In the given figure, option C is pointing towards the correct location of the lunula.
41.
In the figure, what is happening at B?
Correct Answer
D. Epithelium are migrating across wound
Explanation
Epithelium refers to the outermost layer of cells in the body. When a wound occurs, the epithelial cells surrounding the wound begin to migrate across it to facilitate healing. This process is known as epithelial migration. Therefore, in the given figure, the movement of epithelium across the wound is happening at point B.
42.
In the figure, where are the cells that have phagocytic properties?
Correct Answer
D. E
Explanation
The cells that have phagocytic properties and are located at "E" are likely macrophages. Macrophages are a type of white blood cell (leukocyte) that are part of the immune system. They are found throughout the body, residing in tissues such as the spleen, liver, lymph nodes, and connective tissues.
Macrophages play a crucial role in the immune response by engulfing and digesting pathogens, dead cells, and other debris through a process called phagocytosis. They also play a role in antigen presentation, where they display parts of pathogens (antigens) to activate other immune cells such as T cells.
43.
In the figure, where is the blood clot?
Correct Answer
A. A
Explanation
Based on the information provided in the question, it is not possible to determine the location of the blood clot. The figure is not described or shown, so we do not have any visual or contextual clues to make an informed decision. Therefore, an explanation for the correct answer cannot be generated.