Tissue Regeneration and Development

Study Notes

Regeneration of Tissues

Epithelial tissue (skin and mucous membranes) and fibrous connective tissues and bone regenerate easily.
Skeletal muscle regenerates poorly.
Cardiac muscle and nervous tissue within the brain and spinal cord are replaced largely with scar tissue.

Developmental Aspects of Cells and Tissues

Growth through cell division continues through puberty.
Cell populations exposed to friction (such as epithelium) replace lost cells throughout life.
Connective tissue remains mitotic and forms repair (scar) tissue.
Muscle tissue becomes amitotic by the end of puberty, except for some exceptions.
Nervous tissue becomes amitotic shortly after birth.
Injury can severely handicap amitotic tissues.

Aging and Neoplasms

The cause of aging is unknown, but chemical and physical insults, as well as genetic programming, have been proposed as possible causes.
Neoplasms, both benign and cancerous, represent abnormal cell masses in which normal controls on cell division are not working.
Hyperplasia (increase in size) of a tissue or organ may occur when tissue is strongly stimulated or irritated.
Atrophy (decrease in size) of a tissue or organ occurs when the organ is no longer stimulated normally.

Glands of the Integumentary System

Sebaceous (oil) glands are found throughout the entire body except for palms and soles, and produce sebum by holocrine secretion to oil and lubricate.
Sweat glands are found on the entire skin surface except for nipples and part of external genitalia, and help prevent overheating, producing 500 cc to 12 l/day.

Description

Explore the regeneration capabilities of different tissue types, including epithelial, fibrous connective, skeletal muscle, and cardiac muscle. Learn about growth and cell division through puberty and beyond.