Chapter 3 (Part II): Tissues Flashcards
Epithelial (covering), Connective (support), Nervous (control), Muscle (movement). What category of the body are these?
Body tissues
Function: protection, absorption, filtration, secretion. Lining, covering, granular tissue of the body. Layer that protects the body from its environment. All of the substances our body gives off or receive passes through this. Granular version specializes in secretion: sweat, oil, digestive enzymes, and mucus.
Epithelial Tissue
“Glue” that holds the epithelium in place. Structureless material secreted by epithelial cells and connective tissue cells.
Basement Membrane
Cells fit closely together in this layer of tissue to form sheets bound together by cell junctions like desmosomes (tentacles) and tight junctions. Cells are avascular - no blood supply of their own. They depend on diffusion from capillaries in connective tissue for food and oxygen.
Epithelial Tissue
One layer of cells in this classification of epithelium
Simple epithelium
More than one layer of cells in this classification of epithelium
Stratified epithelium
Cells that are flattened like fish scales.
Squamous cells
Thin, single layer of tile-like cells. Usually found where rapid diffusion occurs. Found in alveoli and walls of capillaries.
Simple squamous epithelium
Multiple layered feature, made of specific kind of cells. Found in places that face friction, like surface skin, mouth, and esophagus.
Stratified Squamous Epithelium
Cells that are cube shaped
Cuboidal cells
Common in glands, one layer of this type of cells resting on a basement membrane.
Simple cuboidal epithelium
Column-like cells.
Columnar cells
Single layer of cells that lines the entire length of the digestive tract from stomach to anus.
Simple columnar epithelium
(A subdivision of glandular epithelium) - Ductless gland: secretions are exclusively hormonal and diffuse directly into the blood vessels that weave through the glands (EX: Thyroid, adrenals, pituitary)
Endocrine glands
(A subdivision of glandular epithelium) - Glands have ducts. They are internal and external. They produce sweat and oil. Included are the liver and pancreas.
Exocrine glands
Function of this type of tissue: Protecting, supporting, cushioning, and insulating other body tissues, found all over our body. Consists of living cells surrounded by extracellular matrix (syrupy ground substance). Tissues under this umbrella term are poorly vascularized or avascular all together. (Cartilage, ligaments).
Connective tissues
Produced by secretions of connective tissue cells. Two main elements: Structureless ground substance, made of water, cell adhesion proteins, and large, polysaccharide molecules. Element 2: Fibers.
Variations in matrix give them the ability to form soft packing tissues around other organs to give them weight and to withstand stretching.
Extracellular Matrix
Composed of bone cells sitting in cavities called lacunae. Contains calcium and an abundance of collagen fibers.
Osseous tissue (Bone)
Main cell: Chondrocytes. Collagen fibers provide strength. Forms trachea, windpipe, attached to ribs of breastbone, and covers bone ends at joints.
Cartilage (Connective tissue)
Forms strong, rope like structures so tendons and ligaments can withstand tension in one direction.
Dense connective tissue
General purpose is to rid the body of excess fluid. “Glue” that helps to hold the internal organs together and in proper positions. Provides a reservoir of water and salts for surrounding tissues. Soaks up excess fluid from inflamed areas like a sponge (edema), which creates swelling.
Areolar (Loose connective tissue)
Cells in this tissue’s bodies are mostly occupied by a droplet of far, compressing their nucleus to one side of the cell. This tissue insulates the body and protects specific organs like kidneys and eyeballs.
Adipose (Fat cells)
Network of interwoven fibers. Forms internal framework of organs. Branching, mesh-like appearance.
Reticular connective tissue
General: Carries nutrients, wastes, respiratory gases, white blood cells, and other substance throughout the body. This tissue consists of ____ cells cells surrounded by ______ plasma. Fibers of _______ - soluble proteins only visible during clotting.
Blood (vascular tissue)
This tissue is designed to contract, which provides the force required to produce movement. Irritable (responsive to stimuli). 3 types: skeletal, cardiac, smooth. Irritable and contractile.
Muscle tissue
Flesh of the body, (the muscular system). Has striations, meaning that they contract. When they do contract, they pull on bones or skin, creating body movement, including changes in facial expressions.
Cells are long, cylindrical, and multinucleate. Often referred to as muscle fibers. Features obvious stripes.
Skeletal muscle tissue
Muscle exclusively in the walls of the heart. Has striations and a cells have single nucleus. Cells fit tightly together (like clasped fingers) at junctions called intercalated disks. Junctions allow ions to pass from cell to cell.
Cardial muscle tissue
No striations visible. Flexible, found in walls of hollow organs like the stomach, uterus, and blood vessels. They contract and expand, causing the organ to get smaller or larger so the organ can function.
Smooth Muscle tissue
Irritable, quality of conductivity. Cytoplasm of these cells is extended so they can send impulses to distant body locations. These cells make up this tissue, and they vary in size. Contains brain, spinal cord, and nerves.
Nervous tissue (neurons)
Accomplished in two major ways: regeneration and fibrosis.
Tissue repair
Replacement of destroyed tissue by the same kinds of cells.
Regeneration
Repair by dense connective tissues by the formation of scar tissue. Depends on the type of tissue and severity of the injury.
Fibrosis
Series of events after tissue injury
Inflammation, granulation tissue formation, regeneration/fibrosis: permanent repair
Where the injury occurs, the damaged cells release inflammatory chemicals that makes nearby capillaries very permeable. Fluid, rich in clotting proteins, is released into the bloodstream and hold the edges of the wound together to prevent blood loss. A clot forms, blocking off the exposed area from the rest of the body. When the clot is exposed to air, it scabs.
Inflammation
A pink tissue mostly comprised of new capillaries. Contains Phagocytes, which dispose of blood clots, and Connective Tissue Cells (fibroblasts), which produce scar tissue to permanently bridge the gap.
Granulation Tissue Formation
Epithelium regenerates, makes its way between granulation tissue and scab. Scab detaches. Scar is composed of dense connective tissue (result of Fibrosis).
Regeneration and Fibrosis: Permanent repair
Body tissues/organs enlarge as a result of cells multiplying wildly due to a local irritant or condition that stimulates the cells. Ex. Breast enlargement during pregnancy - due to hormonal increases
Hyperplasia
Bones
Supporting connective tissue
fluid connective tissue
Connective tissue proper
