Integumentary System

What does the epidermis act as a barrier against?

mechanical injury, pathogens, and chemicals.

What does keratin in the skin prevent loss of?

water.

What does sebum from sebaceous glands keep the skin?

moisturized.

What does the skin convert 7-dehydrocholesterol into when exposed to UV light?

cholecalciferol (Vitamin D3).

What do the liver and kidneys process Vitamin D3 into?

calcitriol, the active form needed for calcium absorption.

What do sensory receptors in the skin detect?

stimuli from the environment.

What do Meissner's corpuscles detect?

light touch.

What do Pacinian corpuscles sense?

deep pressure and vibrations.

What do free nerve endings detect?

pain and temperature changes.

What do sweat glands remove as waste?

water, salts, urea, and ammonia.

How does the skin regulate body temperature?

Through vasodilation and vasoconstriction.

What kind of barrier does the skin form against infections?

A physical barrier.

What types of cells are found in the epidermis?

Keratinocytes, melanocytes, Langerhans cells, and Merkel cells.

What is the stratum corneum composed of?

Dead, flattened keratinized cells.

Where is the stratum lucidium present?

Only in thick skin, such as on the palms and soles.

What does the stratum granulosum contain that helps in keratin formation?

Keratohyalin granules.

What layer of the dermis contains Meissner’s corpuscles?

The papillary layer.

What type of connective tissue is the reticular layer of the dermis made up of?

Dense irregular connective tissue.

What does the hypodermis consist of?

Adipose tissue and areolar connective tissue.

What is hair composed of?

Keratinized cells formed in the hair follicle.

Where is terminal hair found?

On the scalp and eyebrows.

What is the visible part of the hair above the skin called?

Hair shaft.

What is the lunula?

The white crescent-shaped area at the base of the nail.

What do eccrine glands secrete?

Watery sweat activated by heat.

What do apocrine glands secrete?

Thicker sweat rich in proteins and lipids.

What do sebaceous glands secrete?

Sebum to moisturize skin and hair.

Where is melanin produced in the epidermis?

In the stratum basale.

What is albinism?

A genetic lack of melanin due to a defect in the tyrosinase enzyme.

The outermost layer of the skin is called the __________.

epidermis.

The primary protein found in skin that provides structure is __________.

keratin.

The glands that produce sweat are called __________ glands.

eccrine.

The process of shedding dead skin cells from the stratum corneum is known as __________.

desquamation.

__________ is the pigment responsible for skin color and protection against UV light.

Melanin.

Hair follicles are found in the __________ layer of the skin.

dermis.

The thick skin found on the palms of the hands and soles of the feet contains a layer called __________.

stratum lucidium.

__________ cells in the epidermis are responsible for the sensation of light touch.

Merkel.

The __________ layer of the dermis is made of loose connective tissue and contains blood vessels and nerves.

papillary.

__________ glands secrete a thicker, protein-rich sweat associated with body odor.

Apocrine.

The __________ is the visible part of the nail that extends beyond the fingertip.

nail plate.

The term for the fatty layer beneath the skin is __________.

hypodermis.

__________ is the process by which the skin regulates temperature through sweating.

Thermoregulation.

Blood vessels in the skin can constrict or dilate, a process known as __________.

vasodilation/vasoconstriction.

The __________ is the whitish crescent-shaped area at the base of a fingernail.

lunula.

What is the main function of the skin?

To act as a protective barrier and regulate various bodily functions.

How many layers does the skin have?

Three main layers: epidermis, dermis, and hypodermis.

What is the role of melanocytes in the skin?

To produce melanin, which gives skin its color and protects against UV radiation.

What are Langerhans cells responsible for?

Participating in the immune response by identifying pathogens.

What is the function of Merkel cells?

They act as mechanoreceptors for the sensation of touch.

Which layer of the skin is primarily responsible for thermoregulation?

The dermis, particularly through the blood vessels.

What is the primary purpose of sebaceous glands?

To produce sebum that helps keep the skin and hair moisturized.

What is the composition of sweat?

Primarily water, salts, and small amounts of urea and ammonia.

How does the skin help with vitamin synthesis?

It synthesizes Vitamin D when exposed to UV radiation.

What defines thick skin compared to thin skin?

Thick skin has a thicker stratum corneum and contains the stratum lucidum.

What type of hair is described as fine and soft?

Vellus hair.

What is the main cellular component of hair?

Keratin.

Where are nail growth and formation primarily located?

In the nail matrix.

What role do ATP-sensitive potassium channels play in the skin?

They help regulate skin barrier function and hydration.

What type of tissue primarily composes the hypodermis?

Loose connective tissue and fat (adipose tissue).

What are the specialized cells that detect pain called?

Nociceptors.

How does the skin contribute to sensory perception?

Through various receptors that detect touch, pressure, pain, and temperature.

What is the structure that anchors hair follicles into the skin?

The hair bulb.

What common skin condition results from clogged sebaceous glands?

Acne.

What is the primary function of the stratum granulosum?

To contribute to the waterproof barrier of the skin.

The outermost layer of skin is the __________.

epidermis.

The layer of skin beneath the epidermis is called the __________.

dermis.

The innermost layer of the skin, which contains fat, is called the __________.

hypodermis.

____________ are cells located in the epidermis that produce melanin.

Melanocytes.

The primary protein that makes up the outer layer of skin is __________.

keratin.

The __________ is a small area of white at the base of the nail.

lunula.

The process of skin cell turnover and shedding is called __________.

desquamation.

The __________ regulates temperature through the mechanisms of sweating and blood flow.

skin.

Sebaceous glands secrete __________ to keep the skin moisturized.

sebum.

The primary function of __________ is to help control body temperature and excrete waste.

sweat glands.

The deeper layer of the dermis contains __________ connective tissue.

dense irregular.

The __________ layer of the dermis contains blood vessels and nerves.

papillary.

__________ glands produce a thicker sweat associated with body odor, typically found in the armpits.

Apocrine.

The type of hair that is fine and soft, often referred to as "peach fuzz," is called __________ hair.

vellus.

__________ corpuscles are responsible for detecting light touch in the skin.

Meissner's.

Pacinian corpuscles primarily detect __________ and vibrations.

deep pressure.

The __________ is a protein-rich substance secreted by sebaceous glands.

sebum.

Any sustained damage leading to skin ulcers or wounds is known as __________.

tissue injury.

The sensation of __________ is detected by free nerve endings in the skin.

pain.

Blood vessels in the skin can __________ to either conserve or release heat.

dilate or constrict.

The process of converting 7-dehydrocholesterol to Vitamin D occurs in the __________ when exposed to sunlight.

skin.

The __________ detects changes in temperature of the environment.

skin.

The small openings on the surface of the skin through which sweat is secreted are called __________.

pores.

The condition resulting from the overproduction of skin cells leading to flaky skin is known as __________.

psoriasis.

The __________ is responsible for protecting the body against UV radiation by absorbing harmful rays.

melanin.

The __________ in hair follicles is responsible for hair growth.

hair bulb.

Skin color variation among individuals is primarily due to differences in __________ production.

melanin.

__________ are specialized cells that are part of the immune system and help protect the skin.

Langerhans cells.

The __________ is the part of the nail that is actively growing beneath the cuticle.

nail matrix.

Conditions that increase skin sensitivity to sunlight are known as __________.

photosensitivity.

The main function of the dermis layer of skin is to provide __________ and support.

strength.

The process by which skin loses moisture is known as __________.

dehydration.

__________ are the nerve endings that sense temperature changes in the skin.

Thermoreceptors.

The primary benefit of having a thick stratum corneum is to provide __________ against injury.

protection.

The __________ is the visible part of the hair that is above the skin's surface.

hair shaft.