Anatomy and physiology Chapter 5 (Epidermis Cell types)

List the layers in order from thick to thin.

1) Basale 2) Spinosoum 3) Granulosum 4) Lucidum 5) Corneum

Where is the stratum lucidum found?

In thick skin. It helps to give the thick skin a little more protection from damage.

What percent of the cells in the stratum basale is made up of melanocytes?

10-25%

What do cells need in order to divide?

Blood. So as the cells move further away from the dermis they lose the capability to divide because they don't have access to blood.

True or False. Dendritic cells are not located in the stratum spinosum.

False.

True or False. The stratum Corneum is the thinnest layer in the epidermis.

False. It's the thickest.

How many layers does the stratum granulosum have?

Five cells layers or less.

The epidermis has a protective protein feature known as _______

Keratin

What is the predominant cell in the epidermis (all layers in the epidermis) ?

Keratinocytes

What are the four cell types in the epidermis?

Keratinocytes, Melanocytes, Dendritic cells, and Tactile cells.

What three cell types are found in the stratum basale?

Keratinocytes, Melanocytes, and Tactile cells.

What are dendritic cells also known as?

Langerhan cells

What are tactile cells also known as?

Merkel cells

There are two different types of epidermis. They are thick skin and thin skin. What are the two examples of thick skin?

Palms, finger tips, and soles of feet.

What are tactile cells?

These are nervous tissue that help us detect light touch. (ex: If a fly lands on you.)

Where is the stratum basale and what takes place here?

The bottom layer of the epidermis. It's a single layer of keratinocytes going through constant mitosis (rapid division). When the cell divides one of them is pushed up towards the surface. Its the only place in the epidermis that cells divide.

What takes place in the stratum spinosum?

The keratinocytes began to make an attachment to there neighbors. This helps with the protective barrier.

Where are melanocytes located?

The stratum basale.

What are melanocytes and what does it provide?

They produce melanin. And it produces skin color.

Keratinization begins to take place in the startum granulosum. The Keratinocytes begin to die off because they are far removed from blood supply. As the Keratinocytes die then begin to fill with keratin and glycolipids (fat). The plasma membrane hardens and the cell becomes flat. This adds a whole other protective layer to our skin. True or False.

True

Melanin forms a protective barrier around the nucleus of the keratinocyte. And that protective barrier protects it from the rays of the sun. And the melanin protects the DNA. And The color that we see on our skin is the melanin at the bottom layer. True or False.

True

True or False. The Keratinocytes in the stratum spinosum contain melanin. The melanocytes make the melanin then give it to the keratinocytes.

True.

Is the epidermis Vascular or Avascular?

avascular

What are dendritic cells?

cells that float around in the epidermis that look for pathogens. They undergo phagocytosis (ingest bacteria) and activate the immune system.

What is the stratum corneum made of?

dead keratinized waterproof cells.

What does stratum mean?

layer

What do the glycolipids help with in keratinization?

make it water proof.

What is the tissue type of the epidermis?

stratified squamous epithelium