Stem Cells and Integumentary System Flashcards

Vocabulary practice flashcards covering stem cell potency, membranes, skin functions, dermal/epidermal layers, and skin cell types based on lecture notes.

Totipotent Stem Cells

Embryonic stem cells that can differentiate into any cell of the umbilicus, placenta, or human organism. They are the most potent stem cells ("toti" = total = all cells possible). Examples include Zygotes, 2-Cell Stage, 4-Cell Stage, and Morula.

Pluripotent Stem Cells

Stem cells able to differentiate into any cell of the fetus, but unable to differentiate into fetal support structures such as any cell of the placenta/umbilicus.

Multipotent Stem Cells

Stem cells able to differentiate into any cell of a given type of tissue.

Unipotent Stem Cells

Stem cells with the most limited potency, able to develop into only ONE cell type. For example, those located in the epidermis are able to only produce epidermal cells.

Morula Stage

The final stage in early embryonic development in which there are totipotent stem cells.

Tissue Membranes

Flexible covering of a tissue or lining a body cavity to prevent friction.

Plasma Membranes

Phospholipid bilayer that encloses a cell.

Epithelial-Containing Membranes

Types of tissue membranes that contain an epithelial layer: Mucus Membrane, Serous Membrane, and Cutaneous Membrane.

Synovial Membranes

Tissue membranes located within joints that lack an epithelial layer and function in fluid production.

Functions of the Skin

Protection, Vitamin D Synthesis, Sensation, Body Temperature Regulation, and Absorption.

Thick Skin

Skin located on the Palms of the Hands and Soles of Feet. Contains an additional layer of Stratum Lucidum in the epidermis that allows for more grip strength in those areas.

Epidermal Layer Count (Thin vs. Thick Skin)

The skin of the arm (thin skin) has 4 layers of epidermis, while the skin of the palm of the hand/soles of feet (thick skin) has 5 layers of epidermis.

Layers of the Skin Diagram

Structural regions of the integument showing the Epidermis, Papillary Region, Reticular Region (Dermis), and Hypodermis.

Melanocytes

Melanin-producing cells in the epidermis. Melanin protects the DNA in skin cells from damaging UV light.

Dendritic Cells

Immune cells found in the epidermis functioning in protection against infection and disease.

Epidermal Stem Cells

Cells in the epidermis responsible for the production of new keratinocytes.

Tactile Cells

Cells found in the epidermis that allow for the sensation of touch.

Keratinocytes

Epidermal cells that produce keratin and make up the stratified squamous epithelium that composes the majority of the skin tissue.

Layers of the Epidermis

Sequence of epidermal layers from superficial to deep: Stratum corneum, Stratum lucidum, Stratum granulosum, Stratum spinosum, Stratum basale.

Stratum Basale

The layer of the epidermis that is the most mitotically active. It contains stem cells and continuously produces new keratinocytes.

Stratum Spinosum

The layer of the epidermis that is the most metabolically active and produces lots of keratin.

Keratinocyte Diffusion & Survival

As keratinocytes move superficially from the stratum basale due to cell production, they move further from the blood nutrient source. Without nutrients, the cell dies and dead skin cells are shed from the stratum corneum.

Papillary Region

Region of the dermis made of Areolar Connective Tissue.

Reticular Region

Region of the dermis made of Dense Irregular Connective Tissue; forms the majority of the dermis.

Dermal Papillae

Structures that produce ridges on the superficial aspect of the dermis, creating a unique pattern of dermal papillae (fingerprints) for every individual.