Exam 4- Skin, Hair and Nails- Anatomy and Physiology

Functions of the skin

Protect against microbial and foregin substance invasion and minor trauma

Retard body fluid floss by via machanical barrior

Reguate body temp via radiation, condtuion, convection adn evaporation

Layers of the skin

Epidermis

Dermis

Hypodermis

Appendages

What is the outermost part of the skin?

Epidermis

The epidermis is ________ and depends on the underlying dermis for its nutrition

A vascular

What are the 2 major layers of the epidermis

Stratum corneum

Cellular stratum

What layer of the epidermis protects the body against harmful environmental substances and restricts water loss

Stratum corneum

What layer of the epidermis is where the keratin cells are synthesized

Cellular stratum

What lies beneath the cellular stratum and connects the epidermis to the dermis

Basement membrane

What is the richly vascular connective tissue layer of the skin and separates the epidermis from the cutaneous adipose tissue

Dermis

What are the components of the dermis that provide resilience, strength and stability

Elastin

Collagen

Reticulum fibers

What component of the dermis provide sensations of pain, touch and temperature

Sensory nerve fibers

What component of the denim is innervates blood vessels, glands and the arrectores pilorum muscles

Autonomic motor nerve

What connects the dermis to the underlying organs and is a subcutaneous layer filled with fatty cells

Hypodermis

Functions of the Hypodermis

Generates heat

Provides insulation

Provides shock absorption

Provides calorie reserve

What open directly into the surface of the skin and regulate body temperature through water secretion?

Eccrine sweat glands

Where are eccrine sweat glands found

Everywhere except:

Lip margins

Eardrums

Nail bed

Inner surface of prepuce

Glans penis

What are larger sweat glands located more deeply than the eccrine glands

Apocrine sweat glands

What do apocrine sweat glands do in response to emotional stimuli

Secrete white fluid containing protein, carbohydrate and other substances

How is body odor produces

Bacterial decomposition of apocrine sweat

Where are apocrine sweat glands found

Axillae

Nipples

Are old

Anogenital area

Eyelids

External ears

What secrete sebum, a lipid rich substance that keeps the skin and hair from drying out

Sebaceous glands

What is formed by epidermal cells that invaginate into the dermal layers

Hair

What provide the color for hair

Melanocytes in the shaft

What are the 2 types of hair that adults have

Vellus

Terminal

What is vellus hair

Short, fine, soft and nonpigmented

What is terminal hair

Coarser, longer thicker and usually pigmented

What are epidermal cells that are converted to hard plates of keratin

Nails

What give the nail its pink color

Highly vascular nail beds that lie beneath the plate

What is the stratum corneum layer of skin covering the nail root?

Cuticle (eponychium)

What is the soft tissue surrounding the nail border

paronychium

Why does skin of infants and children appear smoother than that of adults?

Absence of coarse terminal hair

Skin has not be exposed to years of elements

What is a mixture of sebum and cornfield epidermis that covers the infants body at birth?

Vermix caseosa

Why are newborns predisposed to hypoterhmia

Subcutaneous fat is poorly developed

What is the fine silky hair that covers the newborns body, particularly on the shoulders and back and is shed within 10-14 days?

Lanugo

When do eccrine glands begin to function

After 1 month

What causes the oily appearance on adolescents skin going through puberty

Increased sebum production in response to increased hormone levels

What causes drier skin and less perspiration in older adults

Sebaceous and sweat gland activity decreases

What gives joints and bony prominences a sharp, angular appearance in older adults

Subcutaneous tissue decreases

What causes gray hairs

Decrease in the number of functioning melanocytes