General Pathology & Histotechniques Review PDF

### GENERAL PATHOLOGY AND HISTOTECHNIQUES REVIEW Medical Technology Licensure Exam Review by: Kevin A. Legislador, RMT **BASIC HISTOLOGY** **FOUR PRIMARY TISSUE TYPES** | TISSUE TYPE | DESCRIPTION...

### GENERAL PATHOLOGY AND HISTOTECHNIQUES REVIEW Medical Technology Licensure Exam Review by: Kevin A. Legislador, RMT **BASIC HISTOLOGY** **FOUR PRIMARY TISSUE TYPES** | TISSUE TYPE | DESCRIPTION | | :----------------- | :-------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | Epithelial Tissue | It is the lining, covering, and glandular tissue of the body. Glandular epithelium forms various glands in the body | | Connective Tissue | It connects body parts. It is the most abundant and widely distributed tissue type. | | Muscle Tissue | Highly specialized to contract, or shorten, to produce movement | | Nervous Tissue | Receives and conducts electrochemical impulses from one part of the body to another; thus, irritability and conductivity are its two major functions | **EPITHELIAL TISSUE** * Specialized layers of tissue arising from all three embryonic germ layers, namely, the ectoderm, mesoderm, and endoderm. * Classification 1. According to cell shape: squamous, cuboidal, columnar 2. According to cell arrangement: simple, stratified **DIFFERENT TYPES OF LINING/COVERING EPITHELIUM** | EPITHELIUM TYPE | FOUND IN/DESCRIPTION | | :---------------------------- | :------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | | Simple Squamous | Serous Membranes, Blood Vessels, Air sacs in the Lungs, mesothelium | | Simple Cuboidal | Salivary Glands, Pancreas, Walls of the Kidneys, Surface of Ovaries | | Simple Columnar | Digestive tract from the stomach to the anus **microvilli**. Goblet cells which produce a lubricating mucus are often seen in this type of epithelium | | Pseudostratified Columnar | All of its cells rest on a basement membrane, however, some of its cells are shorter than the others and their nuclei appear at different heights above the basement membrane giving the false (pseudo) impression that it is stratified | | Pseudostratified Ciliated Columnar | Ciliated variety of pseudostratified columnar epithelium that lines most of the respiratory tract | | Stratified Squamous | Mouth, Esophagus, Outer portion of the skin (keratinized) | | Stratified Cuboidal | Rare in the body. Found in ducts of large glands. | Transitional | Urinary bladder, ureters, urethra, Genitourinary tract (GUT) | **CONNECTIVE TISSUE** * All connective tissues originate from embryonic mesenchyme, a tissue developing mainly from the middle layer of the embryo, the mesoderm. * Connective tissue supports organs and cells, acts as a medium for exchange of nutrients and wastes between the blood and tissues, protects against microorganisms, repair damaged tissues, and stores fat. Main Ingredient collagen most abundant protein in the body. **DIFFERENT CONNECTIVE TISSUE TYPES** | CONNECTIVE TISSUE | DESCRIPTION | | :---------------- | :----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | Bone | Sometimes called osseous tissue, composed of bone cells sitting in cavities called lacunae and surrounded by layers of a very hard matrix that contains calcium salts in addition to large numbers of collagen fibers | | Cartilage | Less hard and more flexible than bone. Hyaline Cartilage forms the supporting structures of the larynx, attaches the ribs to the breastbone, and covers the ends of bone where they form joints Fibrocartilage forms the cushion-like disks between the vertebrae of the spinal column Elastic Cartilage supports the external ear | | Dense Connective Tissue | Forms tendons and ligaments: Tendons: attaches skeletal muscles to the bones Ligaments: connect bonos to bones at joints | | Loose Connective Tissue | Softer and has more cells and fewer fibers than any other connective tissue type except blood | | Areolar Tissue | Most widely distributed connective tissue that functions as a universal connective tissue "glue" that helps pack and hold the internal organs in their proper positions | | Adipose Tissue | Commonly called fat that forms the subcutaneous tissue beneath the skin, where it insulates the body and protects it from extremes of both heat and cold | | Reticular Connective Tissue | Forms the stroma or internal framework which can support many free blood cells (largely lymphocytes) in lymphoid organs such as lymph nodes, the spleen and bone marrow | | Blood/Vascular Tissue | Transport vehicle for the cardiovascular system, carrying nutrients, wastes, respiratory gases, etc. | **MUSCLE TISSUE** mesoderm **TYPES OF MUSCLE TISSUE** | Muscle Type | Control | Cells | | :----------------- | :-------------- | :----------------------------------------------------------------------------------------------------------------------------- | | Skeletal Muscle | Voluntary | Long, cylindrical, multinucleated with obvious striations | | Cardiac Muscle | Involuntary | Short, uninucleated, with striations and branching cells that fit together at junctions called Intercalated Disks | | Smooth Muscle | Involuntary | Uninucleated and spindle-shaped with no striations. Found in bladder, stomach, uterus and blood vessels | **NERVOUS TISSUE** * Nervous tissue contains two types of cells. ectoderm 1. Nerve cells (neurons): conduct electrical impulses 2. Supporting cells, which support, nurture, and protect the neurons Brain * CNS: glial/neuroglial cells * PNS: satellite cells, capsule cells, and Schwann cells **BASIC PARTS OF A NEURON** 1. Cell Body (aka: Soma/Perikaryon ): contains the nucleus and the surrounding cytoplasm; primarily the trophic center. 2. Dendrites (Dendron = tree ): often covered with many synapses and are the principal signal reception and processing sites on neurons. receive signals 3. Axon (away from cell body): wrapped in a myelin sheath and is the main conducting unit of a neuron. -to the cell body **MORPHOLOGICAL CLASSIFICATION OF NEURONS** The image shows three types of neurons classified by their morphology: 1. Bipolar Neurons: Possess a single axon and a single dendrite. 2. Multipolar Neurons: Possess a single axon and more than one dendrite. 3. Pseudounipolar Neurons: Possess a single process that extends from the cell body and subsequently branches into an axon and dendrite.