Anatomy and Physiology: Lecture on Skin and its Functions

A comprehensive set of flashcards based on the lecture that covers key concepts in anatomy, physiology, skin structure and functions, and related health conditions.

What detects an increase in temperature in the body?

Thermoreceptors.

2 layers of cutaneous membrane

dermis & epidermis

What are accesory structures of the skin?

Hair follicles, nails, sweat glands, and sebaceous glands.

Where does information from thermoreceptors go?

To the control center in the brain (hypothalamus).

What is the effector in thermoregulation when the body is too hot?

Sweat glands.

What is vasodilation?

The dilation of blood vessels to increase blood flow to the skin surface.

What is the feedback system called that helps the body return to normal temperature?

Negative feedback system.

What happens in response to cold temperatures?

Vasoconstriction of blood vessels in the skin.

What process occurs when the body temperature does not rise sufficiently after vasoconstriction?

Shivering.

What does vitamin D help increase the absorption of?

Calcium. (calcitrol)

What is the precursor to vitamin D produced in the skin?

Dehydrocholesterol.

What is the active form of vitamin D called?

Cholecalciferol (Vitamin D3).

What is the largest storage place for calcium in the body?

The skeletal system (bones).

What is the top layer of the skin called?

Epidermis.

What layer of skin contains blood vessels?

Dermis.

What type of tissue is the epidermis made from?

Stratified squamous epithelium.

What is keratin?

A fibrous protein that prevents water loss and adds strength to the skin.

What is the deepest layer of the epidermis?

Stratum basale.

What happens to cells as they move from the stratum basale to the surface?

They die and lose their nuclei.

What is the function of the stratum granulosum?

Contains keratinized cells providing waterproofing.

In what type of skin do we find the stratum lucidum?

Thick skin.

What is the outermost layer of the epidermis called?

Stratum corneum.

How long does it take for a keratinocyte to migrate through the layers of the epidermis?

About 40 to 45 days.

What type of cell is a Langerhans or dendritic cell?

A phagocytic immune cell.

What do Merkel cells do?

Detect light touch.

What do melanocytes produce?

Melanin.

What gives skin its color?

Melanin, carotene, and hemoglobin.

What is erythema?

Increased redness of the skin.

What is pallor?

Decreased blood flow resulting in paler skin.

What is jaundice?

A yellowish appearance of the skin due to liver dysfunction.

What happens to the body when it loses heat?

Sweating and vasodilation of blood vessels.

What type of secretion do eccrine sweat glands produce?

A watery fluid.

What does apocrine secretion involve?

Thicker sweat associated with hair follicles.

What is sebum?

Oily secretion from sebaceous glands.

What is the most common type of skin cancer?

Basal cell carcinoma.

What is squamous cell carcinoma?

Cancer of keratinocytes in the stratum spinosum.

What is the most deadly type of skin cancer?

Malignant melanoma.

What does the ABCDE rule stand for in skin cancer detection?

Asymmetry, Border irregularity, Color variation, Diameter greater than 6mm, Evolving.

What is a first-degree burn?

Affects only the epidermis; causes redness and mild pain.

What is a second-degree burn?

Affects the epidermis and part of the dermis; causes blistering.

What is a third-degree burn?

Involves the epidermis, dermis, and underlying tissues; may not be painful initially.

What tissues are affected by wounds?

Epidermis, dermis, and possibly deeper tissues.

What is acne caused by?

Accumulation of sebum and dead skin cells within sebaceous glands.

What cells are responsible for forming hair?

Keratinocytes in the hair follicle.

What is hair primarily composed of?

Hard keratin.

What is the purpose of nails?

Protection and tools for various functions.

What is the cuticle of the nail?

The eponychium, or skin at the base of the nail.

What is the hypodermis?

Subcutaneous tissue beneath the dermis.

What are the main components of the dermis?

Collagen and elastic fibers.

What role do adipose tissues play in the skin?

They provide insulation and energy storage.

What is the primary function of sebaceous glands?

To secrete oil (sebum) that lubricates skin and hair.

What is the primary immune cell found in the skin?

Langerhans cells.

What triggers melanin production in the skin?

UV radiation exposure.

What skin condition is characterized by uneven pigmentation and increased melanin production?

Freckles.

How can cell division lead to cancer?

Unchecked cell division creates tumors that can metastasize.

What factors contribute to the aging of the skin?

Decreased collagen, elastin, and fat tissue.

What do you call it when skin cancer spreads to other tissues?

Metastasis.

What action should be taken if a mole changes color or size?

It should be examined by a dermatologist.

What happens to hair and skin cells as they move away from the blood supply?

They die and become keratinized.

What is the most common way for bacteria to contribute to acne outbreaks?

By accumulating in clogged sebaceous glands.