Ch.4 Integumentary system

What are the primary functions of apocrine?

Apocrine glands secrete viscous milky or yellow sweat that contains fatty substances and proteins.

What are the primary functions of eccrine glands?

Eccrine glands secrete sweat that is mostly water.

Know classification of burns and their characteristics

- first degree is on the epidermis, partial thickness burn.
- second-degree burns through the epidermis and can leave blisters with hyper synthesia.
-Third-degree burns destroy dermal tissue and nerves causing a numb sensation.

What gives the nail bed its color?

underlying capillaries

Know what causes skin color and the associated terms. Include homeostatic imbalance

- Melanin, carotene, and hemoglobin.
- Homeostatic imbalance is when the sun's UV rays damage the skin and depress the immune system.

Study all skin cancers and their characteristics. What layers do each arise from? Which spread? What is the treatment? What cells are affected? Which is the most common? Most deadly?

- Basal cell carcinoma, squamous cell carcinoma, melanoma.
- The first two come from the epidermis, they can be removed if caught early, they are not as malignant.
- Basal is least malignant and they all can spread. Surgical excision.
- The most deadly is melanoma which can also be cut out.

Know the characteristics of the epidermis and dermis. What is in each layer? What are the layers? Where does mitosis take place? Which is vascular or avascular? Etc.

- The epidermis is the superficial layer of skin and the dermis is the layer of skin underneath that.
- The epidermis contains keratinocytes, melanocytes, Langerhans cells, and tactile receptors.
- The dermis contains the papillary and reticular layers. -- The epidermis is avascular and the dermis is vascular. Mitosis takes place in the basal layer of the epidermis.

Know about body temperature regulation. What happens to blood vessels in cold and hot environments?

Hot environments cause vessels dilation of dermal vessels, but when temperatures drop, the dermal vessels constrict. Also sweating helps expel heat.

Study melanin and melanocytes.

melanocytes are the cells that produce the chemical melanin that protect the skin from UV radiation.

Do humans have the same number of melanin or melanocytes?

Humans have the same number of melanocytes but different amounts of melanin.

Study the layers of the epidermis. Order of the layers

basale, spinosum, granulosum, lucidum, and corneum

Study the layers of the epidermis.

Study the layers of the epidermis. Know their characteristics. (Thick skin too) Where are there living cells?

- basale is the lowest with the living cells.
- spinosum has spiky keratinocytes called prickle cells
-granulosum is four to six cells thick but the layer is still thin
-lucidum is only found in thick skin, it is thin and clear dead keratinocytes
-corneum is 20-30 layers of dead keratinocytes

Study the layers of the epidermis. Know what EACH layer is next to and how it may affect those layers.

- All of the layers lay one on top of each other and the layers past granulosum begin to die because they are cut off from nutrients
- They are mostly only fed through diffusion of nutrients from other cells.

Know the major regions of the hair shaft

medulla, cortex, cuticle

Know the most important risk of skin cancer. Risk that can lead to skin cancer.

homeostatic imbalance and prolonged sun exposure

Define each skin cancer type and give descriptions of each. Include physical descriptions

- Basal, squamous, melanoma.
- Basal and squamous are small and can be cut out
- Melanoma has symmetry and irregular edges.
- Can look like a mole that's dark.

What are Langerhans cells?

Found in the deep epidermis that patrol for bacteria

What are Merkel cells?

sensory receptor cells that sense touch

What is the lamellated corpuscle?

(found in lab book) Cells that sense pressure

Define alopecia. What makes alopecia areata different from alopecia?

- Alopecia is the thinning of hair after the age of 40 in both sexes.
- Alopecia on the other hand is when the immune system attacks the hair follicles.

Know which glands produce ear wax

Ceruminous glands

Know the characteristics and functions of keratinocytes, dendritic cells, tactile cells, and melanocytes

- cells that produce keratin
- star shaped macrophages that patrol the deep dermis, sensory receptors that sense touch
- cells that produce melanin.

What are the two major layers of the dermis? Which layer makes up the greater percentage in the dermis? What are the characteristics of each?

- Papillary and reticular layers.
- The greater one is the reticular layer.
- The reticular layer connects the dermis to the subcutaneous and contains nerves, fibers, and blood vessels.
- The papillary layer contains papillae that stick onto the epidermis.

What are the two types of sudoriferous glands?

eccrine and apocrine

What are the locations of apocrine glands and eccrine (merocrine glands)?

- Apocrine glands are only found in the genital regions and the armpits (axillary points)
- Eccrine glands are most abundant on the palms. soles. and forehead.

Why would a physician use the rule of nines?

- determine how much skin is burned and how badly.
- 9% of every part of body except 1% genital

What are desmosomes and what might they do in the skin?

(you may have to look back) They anchor cells together and hold the epithelial cells in the epidermis together.

How does the skin fight infection? This will be a higher-level thinking question. You must be familiar with the overall picture of cells, secretions, and junctions.

There are natural barriers within the skin and dendritic cells that helps monitor for bacteria.

Understand the importance of cleavage (tension) lines.

They are important so that when surgeons make incisions, they will heal a lot better.

Define keratin

a fibrous protein that helps form hair, nails, and the outer layer of skin

Define apoptosis

programmed cell death

Define striae

Striae are stretch marks that result from excessive stretching of the skin

Define vellus hair

thin, fine hair that is also known as peach fuzz.

How does melanin protect you?

it protects from UV radiation rays

Define hair root

- Deep to the shaft that penetrates into the dermis, and sometimes into the subcutaneous layer
- the portion that anchors the hair into the skin

Define arrector pili

- Bundle of smooth muscle that is responsible for goose bumps (when stimulated it pulls hair perpendicular to the skin)
- a small smooth muscle attached to the hair follicle

Define hair papilla

- Dermal tissue that contains a knot of capillaries that supplies the hair root with nutrients

Define hair matrix

hair grows from

Define eponychium

nail fold that projects onto surface of nail body

Define hyponychium

area under free edge of plate that accumulates dirt

Define vernix caseosa

sebaceous gland secretion that protects skin of fetus while in watery amniotic fluid

What is another name for your sweat glands?

sudoriferous glands

The layers of the skin as seen on a diagram

epidermis, dermis, subcutaneous