nervous tissue histology ppt nervous tissue histology ppt

Because of this, only specific types of molecules can enter the CNS. 138, 7.18). They can be classified as sensory or autonomic. There are 6 classically recognized layers of the cortex: Pyramidal cells in layers III and V tend to be larger because their axons contribute to efferent projections that extend to other regions of the CNS pyramidal neurons in layer V of motor cortices send projections all the way down to motor neurons in the spinal cord! In addition to pyramidal cells, other nuclei seen in these sections may belong to other neurons or to glial cells also present in the cortex. It provides somatic motor output to skeletal muscles. Study with Quizlet and memorize flashcards containing terms like Afferent, efferent, visceral and more. And there are many different types of neurons. Gray matter is mostly made of neuronal bodies, dendrites and glial cells whereas white matter is made primarily out of myelinated axons. One cell providing support to neurons of the CNS is the astrocyte, so named because it appears to be star-shaped under the microscope (astro- = star). They are considered part of the mononuclear phagocytic system and will proliferate and become actively phagocytic in regions of injury and/or inflammation. Neurons in the dorsal horn are essentially interneurons that project to other regions of the CNS (e.g. Together this gives us the various types of epithelial tissues, such as simple squamous epithelium, stratified cuboidal epithelium, pseudostratified columnar epithelium and many more. Table 2 outlines some common characteristics and functions. These cells have a single, long, nerve tract entering the bottom of the cell body. Satellite cells are found in sensory and autonomic ganglia, where they surround the cell bodies of neurons. If you are a University of Michigan student enrolled in a histology course at the University of Michigan, please click on the following link and use your Kerberos-password for access to download lecture handouts and the other resources. How about the fact that some cardiomyocytes have the ability to secrete hormones that regulate blood pressure? It consists of widely separated mesenchymal cells and ground substance with an abundance of hyaluronic acid. It relays sensory input to cerebellar cortex. Epithelium is classified by both its cellular morphology and the number of cell layers. Be sure you identify the white matter in bothluxol blue-stainedslide 076View ImageandTB&E-stained#076bView Imagesections, as it will appear differently in these two stains. The axons of pyramidal cells will descend through the interior white matter of the cerebrum into the three parts of the brainstem: the midbrain, the pons, and the medulla. 4. Did you know that chronic alcoholics have a lot more smooth endoplasmic reticulum concentrations in their hepatocytes? You may be able to see subtle differences in the distribution of cell types in rather loosely demarcated layers. system is called neurology. They are responsible for the computation and . The ventral spinal cord. The function of myelin will be discussed below. It consists of the mouth, pharynx, esophagus, stomach, small intestine, large intestine and anus. Uploaded on Jun 06, 2013 Elina + Follow cuboidal epithelium water loss The information we provide is grounded on academic literature and peer-reviewed research. I would honestly say that Kenhub cut my study time in half. Astrocytes have many processes extending from their main cell body (not axons or dendrites like neurons, just cell extensions). The glomerulus contains some interesting cells, such as mesangial cells which have supportive and phagocytic properties; juxtaglomerular cells that secrete renin which acts, in a broad sense, to help regulate our blood pressure; podocytes that control the permeability of the filtration membrane; and many more. Ependymal cells, which are uniquely located lining the ventricles of the brain the central canal of the spinal cord, are one notable exception. Click on the tissue and observe. Despite their differences, they all have one thing in common; specialized elongated muscle cells, called muscle fibers. The ovary is actually an organ homologous to the male testis, it gives rise to the gametes (ova) and steroid hormones (estrogen, progesterone). The most common technique used is the hematoxylin and eosin (H&E) stain. Two nodes of Ranvier are circled in Figure 9 below. Myelin is lipid-rich, and on gross inspection appears white. Some neurons are named on the basis of those sorts of classifications (Figure 3). Because the axon hillock represents the beginning of the axon, it is also referred to as the initial segment. Gordana Sendi MD Neuroglia (glial cells) (supporting cells) Human unipolar cells have an axon that emerges from the cell body, but it splits so that the axon can extend along a very long distance. This Power point presentation will allow students to practice the skill of identifying tissue types from 25 histology slides. Some cutting edge research suggests that certain neurons in the CNS do not conform to the standard model of one, and only one axon. Edinburgh: Churchill Livingstone. Because of this, ependymal cells can be considered a component of the BBB, or a place where the BBB breaks down. Epithelial tissue can cover external surfaces (skin), line the inside of hollow organs (intestines) or form glands. The cell body contains the nucleus and most of the major organelles. Name thefunction of the cell marked by the black arrow. They are responsible for the computation and communication that the nervous system provides. Due the nature of histological sampling, it is impossible to see the entirety of a three-foot-long neuron on a single slide. Histology - study of tissues Tissue - a collection of similar cells that group together to perform a specialized function. Nervous tissue. In this electron micrograph, note some of the features you saw in ventral horn motor neurons with the light microscope, such as the large, pale nucleus, prominent nucleolus, Nissl bodies, dendrites and axon. It houses information about each and every structure and process of the cell and organism, in the form of DNA (deoxyribonucleic acid). In the hippocampus orientation Image, observe: In the dentate gyrus orientation Image, observe: The "hilus" is the region where the head of hippocampus abuts the dentate gyrus. within limits that maintain life. As such, nerves do not contain neural cell bodies. Why are perikarya of dorsal horn neurons smaller than those in the ventral horn? Information flows through a neuron from the dendrites, across the cell body, and down the axon. Above the temporal (ventral or inferior) horn of the lateral ventricle the lateral geniculate nucleus is present. Name this exception. Neurons are specialized cells that contain a body (soma) and one or more processes ( dendrites, axons ). With the exception of the unipolar sensory ganglion cells, and the two specific bipolar cells mentioned above, all other neurons are multipolar. Grounded on academic literature and research, validated by experts, and trusted by more than 2 million users. Use the virtual slide of the hippocampal region to study the ependymal cell lining of the choroid plexus. The testes produce male gametes (spermatozoa) via the process of spermatogenesis. Bones articulate with other bones by way of joints, which can be synovial, fibrous or cartilaginous. In a transverse section of a nerve (Figure 10), single myelinated axons look like little circles organized in bundles called fascicles. Tissues. Adjacent to the neuron, note myelinated axons of various sizes and also that there are no spaces between cell processes. The delicate meshwork of dendritic processes and nerve fibers (axons) lying between cells in the gray matter is called the neuropil. The neuron is the structural and functional/electrically excitable unit of the nervous system Nervous system The nervous system is a small and complex system that consists of an intricate network of neural cells (or neurons) and even more glial cells (for support and insulation). Additional sub-classifications are possible, based on the cell specializations. It is made up of gray matter and white matter. The outer cerebellar cortex, shown in Figure 8, is tightly folded and has three distinct layers: Purkinje cells are typically arranged in a single row between the exterior molecular and interior granular layers. . However, the endothelial cells maintain these junctions in response to signals (via foot processes) from ASTROCYTES. Most of the respiratory tract is lined by respiratory mucosa; a pseudostratified columnar ciliated epithelium with mucus producing goblet cells. It provides preganglionic visceral motor output to sympathetic ganglia. Muscle attaches to bone via tendons; bundles of dense regular connective tissue made out of many collagen type I fibers. For example, the simple columnar epithelium of the stomach fundus contains special parietal cells which secrete HCl to break down meat proteins. Therefore, the purkinje cell somewhat resembles a shrub or coral in shape. These hormones regulate a variety of processes, such as metabolism, growth and blood pressure. 1. Tissuesare classified into four basic types: epithelium, connective tissue (includes cartilage, bone and blood), muscle, and nervous tissue. The lateral extension of the ventral horn slide 065-2 contains relatively large, multipolar visceral motor neurons of the intermediolateral cell column that extends from levels T1 through L2 of the spinal cord. Download Presentation Histology of Nervous Tissue An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Learn more about the histology of the upper and lower digestive tract. Nervous tissue is composed of two types of cells, neurons and glial cells. Lateral to this structure is the tail of the caudate. They are organized into lobules, with each lobule containing a parenchyma of seminiferous tubules and a connective tissue stroma. Cells are categorized into various types, all of which perform different functions. It relays sensory input to cerebral cortex. One or more cell processes may also be seen emerging from the neuronal perikaryon. It will also benefit the publication of several new topics (Hematology, Pathogen ID, and Gross Anatomy). They are responsible for the electrical signals that communicate information about sensations, and that produce movements in response to those stimuli, along with inducing thought processes within the brain. Neurons are usually described as having one, and only one, axona fiber that appears as a long cord emerging from the cell body and projects to target cells. 2. The main effector cells of the lymphatic system are the immune system cells. Upon maturation, they are released into the blood, lymph and into secondary lymphoid organs, where they work alongside immune system support cells to carry out a detailed surveillance of potential threats. The other processes of the neuron are dendrites, which receive information from other neurons at specialized areas of contact called synapses. Neurons of the cerebral cortex are of varying shapes and sizes, but the most obvious arepyramidal cells. between a tract and a nerve? Examine the gray matter on each side of the sulcus using first low and then high power. Ross, H. M, Pawlina, W. (2011). Different regions of the nervous system have distinct histological characteristics that make them easily recognizable, under the microscope. 1:00 - 2:55 Cartilage and Bone ppt | pdf | lecture recording. Unipolar cells are exclusively sensory neurons and have two unique characteristics. Primarily, the PNS is made up of the axons of neurons whose cell bodies are located within the CNS (within the brain for cranial nerves and the spinal cord for peripheral nerves yet another way to divide the nervous system based on location). The cells of the genital ducts and glands produce secretions to support this process. Title: PowerPoint Presentation Author: Jennifer Ann Jost Last modified by: Jeff Keyte Created Date: 10/29/2003 10:25:53 PM Document presentation . The most used tool today for examining cells, tissues and organs is optic (light) microscopy. Myelin is a fatty substance that makes the axon appear white. For now, focus just on the morphology of these regions and observe the presence of three distinct layers rather than the six layers found in the cerebral cortex (evolutionarily speaking, the three-layered organization is considered to be "older," so this type of cortex is also known as "archicortex" whereas the "newer" six-layered cerebral cortex is "neocortex"). Based on their functional properties, these are described as either voluntary (skeletal) or involuntary (cardiac and smooth muscle). The first way to classify them is by the number of processes attached to the cell body. Pia mater 2. Tissues join together in different arrangements to form our body organs. 1:00 - 1:50 Nervous Tissue ppt | pdf | lecture recording (for both hours) 2:05 - 2:55 Connective Tissue ppt | pdf. How is this different in the spinal cord? The study of. Neurons are important, but without glial support they would not be able to perform their function. All rights reserved. The excretory system includes the kidneys, ureters, urinary bladder and urethra. Health Information Technology & Services. The three-dimensional shape of these cells makes the immense numbers of connections within the nervous system possible. In the PNS, myelin is produced by Schwann cells, which wrap around the axon. The musculoskeletal system consists of hard tissues (bones, joints, cartilage) and soft tissues (muscles, tendons, ligaments). This accounts for the name, based on their appearance under the microscope. celiac, aorticorenal, and superior/inferior mesenteric ganglia). Nutrient molecules, such as glucose or amino acids, can pass through the BBB, but other molecules cannot. The glial cell is wrapped around the axon several times with little to no cytoplasm between the glial cell layers. A single axon (often called a nerve fiber) leaves the perikaryon and transmits neural signals to other neurons or to the effectororgan (e.g., skeletal muscles) via synapses. They have one axon and two or more dendrites (usually many more). Nails are plates of proliferating keratinized cells that, similar to hair, contain hard keratin. Tissues. A unity of tissues with a more complex set of functions, defined by the combination of structure and function of the comprising tissues. ("3" in the orientation figure) a molecular layer containing dendrites of the pyramidal cells. All cells contain cytoplasm, are surrounded by a membrane, and contain a variety of structures and organelles. The ECM of nervous tissue is rich in ground substance, with little to no protein fibers. Anaxonic neurons are very small, and if you look through a microscope at the standard resolution used in histology (approximately 400X to 1000X total magnification), you will not be able to distinguish any process specifically as an axon or a dendrite. Click on the white box with the question mark on it 4. Within the medulla, most axons will cross over to the opposite hemisphere of the brain from which they originated a process called decussation and then continue within the white matter of the spinal cord, before synapsing with interneurons and lower motor neurons, in the grey matter of the spinal cord. Click on human from the drop down list 5. This is a tapering of the cell body toward the axon fiber. On a longitudinal section, cardiomyocytes appear branched, joined together by specialized junctions called intercalated discs which allow them to quickly exchange electrical impulses and work as a syncytium. 5 Nervous system The introductory part of the chapter is adapted from BC OpenStax Anatomy and Physiology book under the CC BY license. The tools for studying histology are becoming more diverse everyday. . Optic microscopy, also known as light microscopy, uses light from the visible spectrum and combines it with multiple lenses to create a magnified image. The nervous system is responsible for all our. The central axons are so thin that they appear as purple dots in the middle of the lighter-colored circles of myelin. Lining ventricles of the brain, creating CSF. Nicola McLaren MSc Which of the following cell types contributes to maintenance of the blood-brain barrier? There are six types of glial cells. While their origin is not conclusively determined, their function is related to what macrophages do in the rest of the body. 49 Motor nerve cell - Ventral Horn of Rabbit Spinal Cord, MultipolarMotor Neuron Cell BodyView Virtual EM Slide Motor Neuron Cell Body. Glial cells, such as astrocytes, oligodendrocytes, Schwann cells and others, provide support, nourishment, myelination and protection to neurons. Here, the tissue of interest is immersed in a fixative solution. The epidermis is a keratinized stratified squamous epithelium mostly made out of keratinocytes. Specialised cells (melanocytes, Merkels cells, Langerhans cells) and free nerve endings are found within the epidermis, providing pigmentation, protection and sensation. thyroid, ovaries, suprarenal) and individual hormone-secreting cells found in many organs of the body (e.g. Figure 1 shows the relationship of these parts to one another. Oligodendrocytes (another type of glial cell) are responsible for the myelination of CNS axons. Neurons in the dorsal horn are essentially interneurons that project to other regions of the CNS (e.g., motor neurons in the spinal cord or sensory input to the brain), so they have much smaller overall volume and therefore much less metabolic demand compared to motor neurons which project to target muscles that may be more than a meter away. The respiratory system consists of the lungs and a series of passageways (nasal cavities, paranasal sinuses, larynx, trachea and bronchi) that connect alveoli to the external environment. Do you know why some structures stain blue (basophilic) and others pink (eosinophilic)? Spleen and lymph node histology shows an encapsulated meshwork of fibres, in which immune system cells sit. Once urine is formed from the ultrafiltrate, it travels through the excretory pathway of tubes, all of which are lined by transitional epithelium with the exception of some parts of the urethra. They also have cilia on their apical surface to help move the CSF through the ventricular space. The layers of the blood-air barrier comprise of type I pneumocytes, basement membrane and endothelial cells of the capillaries. All content published on Kenhub is reviewed by medical and anatomy experts. They have rectangular bodies and many dendrite like projections stemming from their shorter sides. Slide 076cerebrumcerebrum luxol blue crossView Virtual Slide, Slide 076bcerebrumTB&EView Virtual Slide. Our engaging videos, interactive quizzes, in-depth articles and HD atlas are here to get you top results faster. Histology - Histology. Confusingly, structures within white and grey matter are referred to by different terms, depending on whether they are located in the CNS or the PNS.