Skin CellsKelsey Howard

Period 7

Type of Skin Cells

• Epidermis

• Dermis

• Hypodermis

What is the epidermis?

• It is the upper layer of the skin.• Made of squamous cells; (flat, scaly cell)

About the epidermis

• Deepest part contains melanocytes – Melanocytes create melanin (skin coloring)

• Contains five layers– Stratum basale, Stratum spinosum, Stratum

granulosum, Stratum licidum, Stratum corneum

MELANOCYTES: A pigment-producing cell in the skin,

hair and eye that determines their color

What is the dermis?

• The lower middle layer of the skin.• Composed of tissues

– collagen, elastic tissue, and reticular fibers

COLLAGEN: The principal protein in connective tissue,

this fibrous, structural molecule provides strength

and elasticity to tissue, skin, cartilage, ligaments,

tendons and bones

RETICULAR FIBERS: Connective tissue fibers

About the dermis

• Contains blood vessels, lymph vessels, hair follicles, and glands– Glands produce sweat and regulates sebum, and body

temperature.• Made up of two layers

– Papillary layers (upper) and reticular layers (lower)• Papillary layer contains the thin collagen fibers• Reticular layer contains the thick collagen fibers

What is the hypodermis/subcutaneous layer?

• The innermost/thickest layer of skin.

• Composed of loose connective tissue and adipose cells.

• Contains major blood vessels of the skin.

ADIPOSE CELLS: cells that primarily

compose adipose tissue, specialized in

storing energy as fat.

Structures

• Epidermis– Keratinocytes

• Dermis– Nerve endings, sweat glands, oil glands, hair follicles, blood vessels

• Hypodermis– Fibrous tissue

KERATINOCYTES: type of skin cell that

makes up 95 percent of the epidermis

FIBROUS TISSUE: tissue containing with tight

woven strands of collagen protein

Functions

• Epidermis– Cell renewal and preservation of moisture, vitamins, minerals

and proteins.

• Dermis– Removes waste products of metabolism from the epidermis,

regulation of body temperature, and skin sensations (touch, pain, heat, cold)

• Hypodermis– Provides thermal insulation and absorbs fat

Osmosis or Diffusion?The body’s skin cells take part in osmosis.

Water moves through the dead skin cells in the stratum corneum.

Example:When you go swimming in a pool and your skin looks wrinkly.

Reasoning:The water moves into the dead skin cells and seeps

through the spaces between the dead skin cell flakes,

this makes the skin cells rehydrate and swell and

expand; creating the wrinkly texture.

Cellular Respiration

Our skin needs oxygen to stay healthy.

We take in oxygen and let out carbon dioxide, this allowing cellular respiration to take place in the body.

Cellular respiration is able to take place in the body and while it does oxygen can enter the body through the skin and carbon dioxide can leave the body through the skin.

← dead skin cell

skin cell →

THE END