Epithelial Tissue Flashcards
What is epithelial tissue?
consists of sheets of cells that cover exterior surfaces, line internal cavities and passageways, and form glands.
What are the three embryonic layers that give rise to epithelial cells?
ectoderm, mesoderm, and endoderm.
What are the general functions of epithelial tissue?
Protection, selective permeability, secretion, and sensation.
What is the function of cilia in epithelial tissue?
help move fluids and trapped particles, such as in the respiratory tract and brain ventricles.
What are cell junctions?
Points of contact that connect one cell to another in a tissue.
What is the function of tight junctions?
Form an impermeable barrier between cells, preventing leakage.
What is an anchoring junction?
Mechanically attaches adjacent cells to each other or to the basement membrane.
What is a gap junction?
Allows cytoplasmic communication between adjacent cells, facilitating ion and molecule transfer
What are the two components of the basement membrane?
Basal lamina and the reticular lamina.
What is the basal lamina?
thin extracellular layer beneath epithelial cells that separates them from underlying tissues.
What is the reticular lamina?
a matrix containing collagen and elastin secreted by connective tissue.
What is the apical surface of epithelial cells?
the part of the cell or tissue that faces an open space.
What is the function of the epithelial basement membrane?
Anchors epithelial tissue to the underlying connective tissue and provides structural support.
How do epithelial tissues receive nutrients?
Since epithelial tissue is avascular, it receives nutrients through diffusion or absorption from underlying tissues.
What are the types of epithelial membranes?
Mucous membranes, serous membranes, and the cutaneous membrane (skin).
What is endothelium?
a specific type of epithelium that lines blood vessels and lymphatic vessels.
What is the role of glandular epithelium?
Specializes in secretion and forms glands that release substances such as enzymes and hormones.
How does epithelial tissue contribute to body defense?
It acts as the body’s first line of defense against physical, chemical, and biological wear and tear.
