Skin Anatomy and Physiology

What are the two main layers of the skin?

• Epidermis and Dermis

• Epidermis and Hypodermis

• Dermis and Hypodermis

• Stratum Basale and Stratum Spinosum

Answer explanation

The two main layers of the skin are the Epidermis and Dermis. The Epidermis is the outer layer, while the Dermis lies beneath it, providing structure and support.

The layer below the dermis is called the ______.

• Epidermis

• Hypodermis

• Stratum Corneum

• Stratum Lucidum

Answer explanation

The layer below the dermis is called the hypodermis, also known as subcutaneous tissue. It provides insulation and cushioning, while the epidermis and dermis are the outer layers of the skin.

Which cells in the epidermis are responsible for producing melanin?

• Langerhans cells

• Merkel cells

• Melanocytes

• Fibroblasts

Answer explanation

Melanocytes are the cells in the epidermis responsible for producing melanin, the pigment that gives skin its color. Langerhans cells are involved in immune response, Merkel cells are sensory receptors, and fibroblasts are found in connective tissue.

The stratum corneum is the ______ layer of the epidermis.

• Thinnest

• Thickest

• Middle

• Basal

Answer explanation

The stratum corneum is the outermost layer of the epidermis and is composed of dead skin cells, making it the thickest layer. It provides a protective barrier, distinguishing it from the thinner layers beneath.

The stratum basale is primarily responsible for ______.

• Sensory reception

• Cell division

• Melanin production

• Collagen secretion

Answer explanation

The stratum basale, the deepest layer of the epidermis, is primarily responsible for cell division. It contains actively dividing cells that produce new skin cells, making it crucial for skin regeneration.

Tags

NGSS.HS-LS1-4

Which cells in the skin are involved in sensation?

• Melanocytes

• Merkel cells

• Langerhans cells

• Fibroblasts

Answer explanation

Merkel cells are specialized skin cells that function as mechanoreceptors, playing a key role in the sensation of touch. Unlike melanocytes, Langerhans cells, and fibroblasts, they are directly involved in sensory perception.

The stratum spinosum is located (a)   the stratum basale.

• Above

• Below

• Beside

• Within

Answer explanation

The stratum spinosum is the layer of skin located above the stratum basale. This positioning is crucial for understanding the structure of the epidermis.

Match the following layers with their corresponding positions in the skin structure.

• Layer separating epidermis from dermis

• Stratum Lucidum

• Subcutaneous layer beneath the dermis

• Hypodermis

• Clear layer found in thick skin

• Basement membrane

• Outermost layer of the epidermis

• Stratum Corneum

The skin acts as a barrier to protect against what?

• Microorganisms

• Water loss

• Physical injury

• All of the above.

Answer explanation

The skin serves as a barrier protecting against microorganisms, preventing water loss, and shielding from physical injury. Therefore, it effectively protects against all of the above.

What happens to the skin when body temperature increases?

• It contracts

• It releases sweat

• It becomes dry

• It thickens.

Answer explanation

When body temperature increases, the skin releases sweat to cool down through evaporation. This process helps regulate body temperature, making 'It releases sweat' the correct answer.