Chapter 4: Tissue Level of Organization

Flashcards covering the key vocabulary and definitions from the Tissue Level of Organization lecture notes.

Epithelial Tissue

Lines exterior surfaces of the body, internal cavities, blood vessels, and forms certain glands.

Connective Tissue

Binds cells and organs, protects, supports, and integrates body parts.

Muscle Tissue

Excitable tissue that contracts to provide movement (smooth, skeletal, cardiac).

Nervous Tissue

Excitable tissue that propagates electrochemical signals (nerve impulses) to communicate between different regions of the body.

Apical Side (Epithelial Tissue)

Faces the cavity, intestinal lumen, stomach lumen, inside of esophagus, inside of tracheae, nasal cavity, mouth cavity.

Basal Side (Epithelial Tissue)

Attached to the basement membrane, which is attached to connective tissue.

Tight Junctions

Cell junctions that prevent transport between cells.

Anchoring Junctions

Cell junctions that help stabilize epithelial tissues (desmosomes and adherens junctions).

Gap Junctions

Cell junctions that form pores between cells, creating continuous cytoplasm.

Squamous Epithelium

Thin, scale-like epithelial cells.

Cuboidal Epithelium

Cube-like epithelial cells.

Columnar Epithelium

Epithelial cells that are longer than they are wide.

Simple Epithelium

Single layer of epithelial cells.

Stratified Epithelium

Several layers of epithelial cells.

Pseudostratified Epithelium

Single layer of irregular epithelial cells.

Endocrine Gland

Gland that secretes directly into surrounding tissues and fluids (e.g., hormones).

Exocrine Gland

Gland that secretes through a duct that opens to the external environment (e.g., mucus, sweat, saliva, breast milk).

Goblet Cells

Mucous-secreting single gland cells of the small intestine.

Merocrine Secretion

Exocytosis of vesicles from the apical surface of a cell (e.g., saliva, eccrine sweat glands).

Apocrine Secretion

A portion of the cell pinches off to release secretions (e.g., apocrine sweat glands).

Holocrine Secretion

The entire cell is shed to release its contents (e.g., sebaceous glands).

Collagen Fibers

Protein fibers that provide tensile strength (e.g., ligaments and tendons).

Elastic Fibers

Protein fibers that stretch (e.g., skin, vertebral column).

Reticular Fibers

Branched collagen fibers that anchor and support (e.g., liver and spleen).

Fibroblasts

Connective tissue cells that secrete the matrix.

Chondrocytes

Cartilage cells embedded within a matrix of collagenous fibers and chondroitin sulfates.

Osteocytes

Bone cells located within lacunae.

Erythrocytes

Red blood cells, transport oxygen and some CO2.

Leukocytes

White blood cells, defense against invading organisms.

Platelets

Cell fragments involved in blood clotting.

Neurons

Nervous tissue cells that form action potentials.

Neuroglia

Glial cells that support neurons.

Skeletal Muscle Tissue

Voluntary, striated, and multinucleated muscle tissue attached to bones.

Cardiac Muscle Tissue

Involuntary, striated muscle tissue with mostly a single nucleus, found in the heart.

Smooth Muscle Tissue

Involuntary muscle tissue with a single nucleus and no striations, found in internal organs.

Carcinoma

Cancer derived from epithelial cells.

Sarcoma

Cancer derived from connective tissue.