Skin Cells and Layers Quiz

Skin Structure and Function

• The epidermis is responsible for protection as a physical barrier against injury, UV light, and bacterial invasion.
• The main function of sweat in relation to body temperature regulation is to evaporate and cool the body.
• The dermis contains nerve endings and receptor cells responsible for detecting stimuli such as temperature, pain, pressure, and touch.
• The integumentary system is an organ because it consists of multiple tissue types that work together to perform specific functions.

Skin Layers

• The dermis is the thickest connective tissue layer.
• The stratum corneum is the layer of the epidermis that contains dead cells filled with keratin.
• The stratum basale is the layer of the epidermis where cells eventually die.

Hair and Sweat

• The main function of hair (pili) is to provide protection from the environment and aid in sensation.
• Eccrine sweat glands are more commonly found in the palms of the hands and soles of the feet.
• Apocrine glands, found in the axillary and pubic regions, produce sweat that causes body odor.

Nerve Endings and Sensation

• Meissner's corpuscles, responsible for touch sensation, are located in the dermis.
• Merkel cells, responsible for sensing pressure and vibration, are located in the stratum basale.

Skin Cells

• Melanocytes are the cell type in the epidermis responsible for producing the brownish/black pigment called melanin.
• Keratinocytes are the most abundant cell type in the epidermis that produce keratin, a fibrous protein.
• Langerhans' cells are involved in immunity and defense against pathogens.

Skin Functions

• The primary function of sweat excretion from the body surface is to regulate body temperature.
• Vasodilation plays a role in the regulation of body temperature by increasing blood flow to the skin.
• Calcitriol plays a role in the body by regulating calcium levels.
• The function of nails is to protect the tips of the fingers and toes.

Other

• The hypodermis is located beneath the dermis and consists of fatty tissue.
• Arrector pili muscles, located in the hypodermis, contract due to fright, cold, and emotions, pulling the hair into a vertical position.
• Stretch marks (striae) are caused by the tearing of the dermis.
• Race is not determined by skin characteristics, but rather by genetics.