Chapter 5: The Human Tissues Flashcards
Histology
The study of tissues and how they are arranged into organs.
Tissues
A group of similar cells and cell products that arise from the same region of the embryo and work together to perform a specific structural role in an organ,
What are the four primary tissues?
Epithelial, Connective, Nervous, and Muscular
Matrix/Extracellular Material
The surroundings of the cell
Ground Substance
Contains water, gases, minerals, nutrients, wastes, hormones, and other chemicals.
What are the 3 primary germ layers?
Ectoderm, endoderm, and mesoderm.
Ectoderm
The outermost germ layer which creates in epidermis and the nervous system.
Endoderm
The innermost germ layer which creates mucous membranes of the digestive and respiratory tract.
Mesoderm
The middle germ layer which is made of loosely organized cells.
Mesenchyme
Gelatinous tissues which the mesoderm turns into. Composed of fine, wispy collagen.
Fixative
A chemical such as formalin that prevents decay
Stains
Provide color to sections mounted on slide for a microscope.
Longitudinal Section
A tissue cut on its long axis.
Cross Section
One cut perpendicular to a cut on the long axis of a tissue,
Oblique Section
A section cut on a slant.
Smears
When the tissue is rubbed or spread across the slide rather than sliced.
Spreads
When a tissue is laid out on the slide
Epithelial Tissue
Consists of sheet of closely adhering, one or more cells thick, with the upper surface usually exposed to the environment or to an internal space in the body.
What are the 6 functions of the epithelial tissue?
Protection, secretion, excretion, absorption, filtration, and sensation.
Basement Membrane
Layer between an epithelium and the underlying connective tissue. Contains collagen, glycoproteins, and other protein carbohydrate complexes.
Basal Surface
The surface of an epithelial cell that faces the basement membrane/face away from the body surface.
Apical Surface
The surface of an epithelial cell that faces away from the basement membrane/towards the body surface.
Lateral Surface
The sidewall of the cell which lies between the basal and the apical surface.
Simple Epithelium
Has only one layer of cells.
What are the 4 types of simple epithelium?
Simple squamous, simple cuboidal, pseudostratified columnar, and simple columnar.
Pseudostratified Columnar
The 4th type of simple epithelial tissue where not all cells reach the surface and the shorter cells are covered by the taller one.
Goblet Cells
Produce protective mucous-like coverings that coat the mucous membrane.
Stratified Epithelia
Ranges from 2-20 layer of cells with some resting atop one another. The deepest layer is connected to the basement membrane.
What are the 4 kinds of stratified epithelia?
Stratified squamous, stratified cuboidal, urothelium, and stratified columnar.
Urothelium
The unique kind of stratified epithelia for the urinary system.
List the 3 MAIN kinds of stratified epithelia from most common to rarest…
Stratified squamous then stratified cuboidal then stratified columnar.
Keratinized Epithelium
Epithelia that is covered with a layer of dead compressed cells.
Biopsy
The removal and microscopic examination of a sample of living tissue.
Connective Tissue
The most abundant tissues in the body which take up less space in the extracellular matrix.
What are the 8 functions of connective tissue?
Binding organs, support, physical protection, immune protection, movement, storage, heat production, and transport.
Fibrous Connective Tissue
Connective tissues which contain conspicuous fibers.
Fibroblasts (Component of Fibrous Connective Tissue)
Large, fusiform or stellate cells which produce the fibers and ground substance that form the matrix of a tissue.
Macrophages (Component of Fibrous Connective Tissue)
Large phagocytic cells that destroy bacteria, foreign particles and dead/dying cells.
Leukocytes (Component of Fibrous Connective Tissue)
White blood cells which travel briefly in the blood stream and react against bacteria, toxins and other foreign agents.
Plasma Cells (Component of Fibrous Connective Tissue)
Synthesize disease-fighting proteins called antibodies.
Mast Cells (Component of Fibrous Connective Tissue)
Secret3 chemicals called heparin and histamine which inhibit blood clotting and increase blood flow subsequently
Adipocytes (Component of Fibrous Connective Tissue)
Fat cells which appear in small cluster and dominate a cell making it adipose tissue.
Collagenous Fibers
Fibers made of collagen which are tough, flexible, and resist stretching.
Reticular Fibers
Thin collagen fibers coated with glycoprotein. Form a spongelike framework for organs such as the spleen and lymph nodes.
Elastic Fibers
Extremely thin fibers that branch out and rejoin each other. Made out of the protein elastin.
Glycosaminoglycan (GAG)
A long polysaccharide composed of unusual disaccharides called amino sugars and uronic acid. Negatively chard and absorb and retain water.
Chondrotin Sulfate (GAG)
The most common GAG. Abundant in blood vessels.
Proteoglycans
Form thick colloids similar to those of gravy. This gel slows the spread of pathogenic organisms through the tissues.
Adhesive Glycoproteins
Bind plasma membrane poteins to extracellular collagen and proteoglycans.
Loose Connective Tissue
Much of the space is occupied by ground substance.
Dense Connective Tissue
Fiber occupies more space than the cells and ground substance. Tissue appears tightly packed.
Areolar Tissue
Loosely organized fibers, abundant blood vessels, and a lot of seemingly empty space. Highly variable experience.
Reticular Tissue
A mesh of reticular fibers and fibroblasts. It forms the framework of the lymph nodes, spleen, thymus, and bone marrow.
Dense Regular Connective Tissue
Closely packed collagen fibers that are also parallel to each other.
