Connective Tissue: Membranes Flashcards

Membranes

• Membranes are pliable tissue sheets covering or lining body parts.

Epithelial Membranes

• Comprise an epithelial layer and a connective tissue layer (lamina propria).
• Include mucous, serous, and cutaneous membranes.

Synovial Membranes

• Line joints and consist only of connective tissue.
• Contain no epithelial cells; special cells secrete synovial fluid.

Mucous Membranes

• Line cavities opening to the exterior (e.g., mouth, stomach).
• Feature tight junctions to prevent diffusion; mucous keeps surfaces moist.

Lamina Propria

• The connective tissue layer found in mucous membranes.

Serous Membranes

• Comprised of simple squamous cells over a loose connective tissue layer.
• Form parietal and visceral layers; line pleura, peritoneum, and pericardium.
• Can lead to pleurisy, peritonitis, or pericarditis when serous fluid accumulates.

Cutaneous Membranes

• Comprise the epidermis and dermis; cover body surfaces.

Muscle Tissue

• Made of fibers modified for contraction, providing motion, posture, and heat production.

Skeletal Muscle Tissue

• Striated, voluntary muscle attached to bones; features long cylindrical cells with multiple nuclei.

Cardiac Muscle Tissue

• Striated, involuntary muscle forming the heart wall; consists of branched cylinders with a single central nucleus.

Smooth (Visceral) Muscle Tissue

• Found in hollow internal structures (e.g., blood vessels, viscera).
• Non-striated and involuntary; regulates blood vessel constriction and digestive tract propulsion.

Nervous Tissue

• Consists of two primary cell types: neurons and neuroglia.

Neurons

• Sensitive to stimuli; convert and conduct nerve impulses to other cells.
• Comprised of a cell body, dendrites, and axons.

Dendrites

• Carry signals toward the cell body.

Axons

• Transmit signals away from the cell body.

Excitable Cells

• Neurons and muscle fibers can generate action potentials (electrical excitability).

Tissue Repair

• Involves replacing damaged or dead cells; varies by tissue type.

Epithelial Repair

• Achieved through the division of stem or undifferentiated cells.

Connective Tissue Repair

• Bone shows continuous renewal capacity; cartilage renews less frequently.

Muscle Repair

• Muscle cells have limited renewal ability.

Nervous Tissue Repair

• Has the least capacity for renewal among tissue types.

Fibrosis

• Characterized by scar formation; extensive injuries may lead to granulation tissue development.

Adhesions

• Result from scar tissue; can cause abnormal tissue joining, leading to complications like intestinal obstruction.

Tissue Engineering

• Involves laboratory-grown new tissues, such as skin and cartilage, with scaffolding for cell growth.

Conditions Affecting Tissue Repair

• Factors include nutrition, blood circulation, and aging.

Nutrition: Affecting Tissue Repair

• Adequate protein supports structural integrity; vitamin C is crucial for collagen and blood vessel production.

Blood Circulation: Affecting Tissue Repair

• Proper circulation delivers oxygen and nutrients while removing waste and bacteria.

Aging: Affecting Tissue Repair

• Collagen quality declines, elastin fibers can abnormally bond to calcium, and cell division/protein synthesis slow down.

Disorders: Homeostatic Imbalances

• Specific organ disorders, such as skin cancer, impact epithelial tissues.

Autoimmune Disorders

• Commonly affect connective tissues; antibodies mistakenly target the body's own tissues.

Sjögren's Syndrome

• Results in exocrine gland inflammation, causing dry mouth and eyes, affecting 20% of older adults.

Systemic Lupus Erythematosus (SLE)

• Chronic connective tissue inflammation primarily affects nonwhite women during childbearing years; can be life-threatening if major organs are involved.