Skin

What type of epithelium is epidermis

stratified squamous epithelium that sits ona basement membrane.

Epidermis is vascular or avascular

Avascular

What are the four main functions of the dermis?

1. instructs differentiation of epidermis 2. sends projections called dermal papilla into the epidermis 3. mostly extravascular matrix of collagen type I and elastin 4. contains vasculature of skin

Match each layer with their corresponding characteristic. 1. Contains dividing basal keratinocytes 2. Cells are attached to each other by desmosomes. 3. There are basophilic keratohyalin granules and keratin filaments. 4. This is the first layer where keratin appears 5. This is the first layer of skin where there is no nuclei 6. There are no nuclei in this layer

1. stratum basale = contains dividing basal keratinocytes 2. Stratum spinosum = cells are attached toe each other by desmosomes 3. There are basophilic keratonhyalin granules and keratin filaments = Stratum granulosm 4. First layer where keratin appears = stratum spinosum 5. This is the first layer of skin where there are no nuclei = stratum lucidum (only in thick skin, i.e. palms, soles) 6. There are no nuclei in this layer = stratum corneum

Where are Langerhans cells found?

All layers of the epidermis. these are specialized dendritic cells.

Subaceous glands are found in the dermis or epidermis

Dermis, These glands are in the dermis, usually attached to the hair follicle. They consist of acini attached to a duct that empties into the follicle. Basal cells, arising from stem cells in the bulge, within the gland divide and differentiate to fill with fat droplets.

The three major layers of the skin are (epidermis and dermis)

Epidermis, dermis and hypodermis

Keratinocytes are found in the dermis, true or false.

FALSE. Keratinocytes are the main cell in the epidermis.

How many layers are the epidermis divided into? Which one is only present in thick skin?

Five Stratum lucidum

Arrange these layers in order of superficial to deep Stratum granulosum Stratum spinosum Basal layer Stratum Corneum Stratum lucidum

From superficial to deep Stratum corneum stratum lucidum stratum granulosum stratum spinosum Stratum basale (or basale layer)

The stem cells we now are located in the basal layer of the epidermis. The deepest layer contains the most __________ cell type.

Immature. It idifferentiates and pushes each layer up.

Where are fibroblasts found?

In the dermis, they participate in wound healing

What is the major cell type in the epidermis?

Keritinocytes

The main types of cells found in the epidermis are

Langerhan cells (specialized dendritic) found in all layer's of the epidermis Melanocytes, pigment, found in the stratum basale. Merkel cells, cutaneous sensory, location, stratum basale

The main types of cells found in the dermis are

Meisners and pacinian corpuscles, where meisners are found in the dermal papillae, and fibroblasts, mast cells, and macrophages.

Where are merkel cells found?

Merkel cells are found in the stratum basale in the epidermis. These are cutaneous sensory cells.

Where are melanocytes found?

Stratum basale in the epidermis, these are pigmentation of hair and skin, derived from neural crest cells.

Where are Meisner's and Pacinian corpuscles found?

They're found in the dermis. Meisner's are light sensation and Pacinian are deep pressure (have large receptor. . Meisner = found in the dermal papillae Pacinian = found in the subcutaneous tissue.

Dermis is made up of connective tissue of mesodermal origin and it's where vasculature is / immune cells, and fibroblasts which participate in healing. True or false.

True!

Macrophages and mast cells are found in the dermis. True or False

True. Not the epidermis. Mast cells release granules containing histamine, play role in inflammation. Macrophages = critical component of innate immunity, phagocytize antigens.