Test 2 chapter 6 nervous tissue lab
Endoneurium - connective tissue surrounding individual nerve fibers.
Peripheral Nerve
Nerves Parasympathetic Ganglion
- are seen in cross-section as bundles between individual ganglia.
Satellite (or Capsule) Cells ----Parasympathetic Ganglion
- glial cells with small nuclei at the periphery of nerve cell bodies.
Ganglion Cells Parasympathetic Ganglion
- large, nerve cell bodies with prominent nuclei and nucleoli with a basophilic cytoplasm. Unlike sympathetic ganglia, nuclei are eccentrically located within the cells.
8. Determine if the nerve fibers are myelinated or unmyelinated. How can you tell? Name the cell responsible for myelination.
Answer: Yes, these nerve fibers are myelinated. The gray wrapping is the myelin sheath. The cell responsible for this myelination is the Schwann cells
.Mention the 4 types of glial cells present in the central nervous system (CNS) and the 2 types present in the peripheral nervous system.(PNS)
Central Nervous System: Microglia, astrocytes, oligodendrocytes, and ependymal cells Peripheral Nervous SystemSchwann cells and satellite cells
Identify the three structural types of neurons shown in the image below and provide a brief description on how you were able to identify them .
Multipolar: many short dendrites to one side and one long axon to the opposite side. Bipolar: One long dendrite to one side and one axon to the other side of the cell. Unipolar: axon and dendrite are in one side of the cell and they fuse together.
Epineurium - dense irregular connective tissue surrounding the entire nerve.
Peripheral Nerve
Nodes of Ranvier
Nodes of Ranvier function
Auerbach's (or myenteric) plexus.
Parasympathetic Ganglion
Endocrine Parasympathetic Ganglion
Parasympathetic Ganglion
Exocrine Parasympathetic Ganglion
Parasympathetic Ganglion
Ganglion Cells and Satellite (or Capsule) Cells
Parasympathetic Ganglion
Inner Layer - a circular layer of muscle cells
Parasympathetic Ganglion
Outer Layer - a longitudinal layer of muscle cells
Parasympathetic Ganglion
Parasympathetic ganglia are part of the autonomic nervous system. Most are small ganglia located near or within the organs they innervate. The pancreas is an organ of the digestive system composed of two types of cells: Exocrine - most of the pancreas is composed of acinar cells that secrete digestive enzymes into the small intestine. Endocrine - scattered islets of Langerhans that contain cells that secrete hormones (insulin and glucagon) into the blood. Parasympathetic ganglia occur infrequently in the pancreas and contribute the regulation of secretion from both parts of the pancreas. This specimen contains an excellent example of a ganglion that is easily confused with small islets at low magnification. At higher magnification, the typical structure of an automatic ganglion is evident. Ganglion Cells - large, nerve cell bodies with prominent nuclei and nucleoli with basophilic cytoplasm. Unlike sympathetic ganglia, nuclei are eccentrically located within the cells. Satellite (or Capsule) Cells - glial cells with small nuclei at the periphery of nerve cell bodies. A small cross-section of another ganglion can also be seen.
Parasympathetic Ganglion
Peripheral nerves contain the axons of both motor neurons and sensory neurons that connect with the spinal cord. They are surrounded by multiple layers of connective tissue.
Parasympathetic Ganglion
connective tissue (lamina propria)
Parasympathetic Ganglion
ganglion Parasympathetic Ganglion
Parasympathetic Ganglion
ganglion cells and Satellite (or Capsule) Cells Parasympathetic Ganglion
Parasympathetic Ganglion
goblet cells in the epithelium
Parasympathetic Ganglion
inner circular Auerbach's (or myenteric) Plexus
Parasympathetic Ganglion
outer circular Auerbach's (or myenteric) Plexus
Parasympathetic Ganglion
plexus
Parasympathetic Ganglion
A mechanoreceptor is a sensory receptor that responds to mechanical pressure or distortion. Two types are easily seen in skin from fingers or lips. Meissner's Corpuscle - nerve endings in skin responsible for sensitivity to light touch. Elliptical structures located in projections of connective tissue (dermal papillae) into the stratified squamous keratinized epithelium (epidermis). Each corpuscle consists of an unmyelinated axon meandering between Schwann cells arranged as horizontal lamellae surrounded by a connective tissue capsule.Additional examples: #1, #2, #3 and #4.
Peripheral Nerve
Cellular Layer - inner cellular layer (3 to 8 cells thick) of flattened fibroblasts (blue/gray cells)
Peripheral Nerve
Each corpuscle contains an inner bulb of an unmyelinated axon within a fluid-filled cavity formed by several lamellae of Schwann cells.
Peripheral Nerve
Endoneurium - connective tissue surrounding individual nerve fibers
Peripheral Nerve
Endoneurium - connective tissue surrounding individual nerve fibers within nerves.
Peripheral Nerve
Dorsal Root Ganglion (right)
Sympathetic Ganglia
Fibroblasts - their long, narrow nuclei are scattered within the nerve. In cross-section, they appear as small round nuclei. (The most common type of nuclei seen within the nerves.
Peripheral Nerve
Fibrous Layer - an outer layer of connective tissue (blue) that is similar to the endoneurium.
Peripheral Nerve
Large oval or spherical structures of 20 to 60 concentric lamellae located in the dense irregular connective tissue (dermis) underneath the epithelium.
Peripheral Nerve
Mesentery contains many small (splanchnic) nerves that are mostly seen in cross-section. Each of these nerves consists of a bundle of nerve fibers (fascicles). Connective tissue:Epineurium - dense irregular connective tissue surrounding each nerve. Perineurium - because there is a single fascicle in these small nerves, the perineurium is found immediately inside the epineurium. It consists of two parts:Fibrous Layer - an outer layer of connective tissue that is indistinguishable from the epineurium.. Cellular Layer - inner cellular layer (3 to 8 cells thick) of flattened fibroblasts.Endoneurium - connective tissue surrounding individual nerve fibers. Nerve Fibers - have a wavy appearance and are seen in both cross-sections and longitudinal sections. Schwann Cells - their large round to oval nuclei are seen infrequently seen alongside nerve fibers. Fibroblasts - their long, narrow nuclei are scattered within the nerve. In cross-section, they appear as small round nuclei. (The most common type of nuclei seen within the nerves.)
Peripheral Nerve
Nerve Fascicle - bundle of nerve fibers surrounded by a perineurium. Connective tissue is also seen within fascicles associated with blood vessels.
Peripheral Nerve
Nerve Fibers - besides axons of different diameters seen in cross-section, little detail can be seen.
Peripheral Nerve
Nerve Fibers - have a wavy appearance and are seen in both cross-sections and longitudinal sections.
Peripheral Nerve
Nerve fibers
Peripheral Nerve
Pacinian Corpuscle (or lamellar corpuscles) - nerve endings in skin responsible for sensitivity to vibration and pressure.Large oval or spherical structures of 20 to 60 concentric lamellae located in the dense irregular connective tissue (dermis) underneath the epithelium. Each corpuscle contains an inner bulb of an unmyelinated axon within a fluid-filled cavity formed by several lamellae of Schwann cells. Most of the corpuscle is concentric lamellae separated by fluid. The flattened cells that form these are fibroblasts similar to those located in the endoneurium around peripheral nerves. Deformation of the lamellae increases pressure on the axon causing the generation of nerve impulses. Additional examples: #1 (two Pacinian corpuscles and adjacent nerve) and #2 (two Pacinian corpuscles).
Peripheral Nerve
Perineurium - because there is a single fascicle in these small nerves, the perineurium is found immediately inside the epineurium. It consists of two parts
Peripheral Nerve
Perineurium - connective tissue surrounding a bundle of nerve fibers (fascicle) within nerves.
Peripheral Nerve
Perineurium - connective tissue surrounding a bundle of nerve fibers (fascicle). It consists of two parts:
Peripheral Nerve
Peripheral Nerve
Peripheral Nerve
Schwann Cells - their large round to oval nuclei are seen infrequently seen alongside nerve fibers.
Peripheral Nerve
Schwann cells
Peripheral Nerve
Schwann cells - glial cells with large, round to oval nuclei. The myelin sheath appears as striated pink/red material between axons and the endoneurium.
Peripheral Nerve
The nervous system has a variety of specialized receptors. Meissner's and Pacinian corpuscles are two that can be readily seen by H&E.
Peripheral Nerve
Ganglion Cells - large, nerve cell bodies with centrally located nuclei and prominent nucleoli. The cytoplasm contains abundant Nissl substance.
Sympathetic Ganglia
Ganglion Cells - large, nerve cell bodies with prominent nuclei and nucleoli.
Sympathetic Ganglia
Each corpuscle consists of an unmyelinated axon (not visible by light microscopy) meandering between Schwann cells arranged as horizontal lamellae surrounded by a connective tissue capsule.
Sensory Nerve Endings
Each corpuscle consists of an unmyelinated axon meandering between Schwann cells arranged as horizontal lamellae surrounded by a connective tissue capsule.
Sensory Nerve Endings
Each corpuscle contains an inner bulb of an unmyelinated axon within a fluid-filled cavity formed by several lamellae of Schwann cells.
Sensory Nerve Endings
Elliptical structures located in projections of connective tissue (dermal papillae) into the stratified squamous keratinized epithelium (epidermis).
Sensory Nerve Endings
Pacinian corpuscles (#1 and #2) are large oval or spherical structures of 20 to 60 concentric lamellae.
Sensory Nerve Endings
Pacinian corpuscles (or lamellar corpuscles) are nerve endings responsible for sensitivity to vibration and pressure. They occur in skin, mesentery, and in joints. Mesentery is composed of loose connective tissue. This section is stained with H&E. Pacinian corpuscles are large oval or spherical structures of 20 to 60 concentric lamellae located in the loose connective tissue of mesentery. Each corpuscle contains an inner bulb of an unmyelinated axon within a fluid-filled cavity formed by several lamellae of Schwann cells. Most of the corpuscle is concentric lamellae separated by fluid. The flattened cells that form these are fibroblasts similar to those located in the endoneurium outside the capsule. Deformation of the lamellae increases pressure on the axon causing the generation of nerve impulses.
Sensory Nerve Endings
Pacinian corpuscles (or lamellar corpuscles) are nerve endings responsible for sensitivity to vibration and pressure. They occur in skin, mesentery, joints, and some abdominal organs (notably the pancreas). This section of pancreas is stained with Masson's trichrome to show connective tissue (blue), nuclei (bright red) and cytoplasm (red/magenta). Pacinian corpuscles (#1 and #2) are large oval or spherical structures of 20 to 60 concentric lamellae. At its center (#1 and #2) is an unmyelinated axon of a sensory neuron and several lamellae of Schwann cells. Most of the corpuscle is concentric lamellae separated by fluid. The flattened cells that form these are fibroblasts similar to those located in the endoneurium around peripheral nerves. Deformation of the lamellae increases pressure on the axon causing the generation of nerve impulses.
Sensory Nerve Endings
Pacinian corpuscles are large oval or spherical structures of 20 to 60 concentric lamellae located in the loose connective tissue of mesentery.
Sensory Nerve Endings
They are elliptical structures located in projections of connective tissue (dermal papillae) into the stratified squamous keratinized epithelium (epidermis).
Sensory Nerve Endings
Dorsal Root Ganglion (left
Sympathetic Ganglia
Nerves - individual nerve fibers are difficult to identify because most are small unmyelinated or only lightly myelinated axons. This is in contrast to the larger, myelinated axons from the dorsal root ganglion.
Sympathetic Ganglia
Identify the following structures present in the Central Nervous System.
Type of cell: Purkinje cells
Ganglion Cells - large, nerve cell bodies with large nuclei, prominent nucleoli, and basophilic cytoplasm. Unlike sympathetic ganglia, nuclei are eccentrically located within the cells.
and Satellite (or Capsule) Cells glial cells at the periphery of nerve cell bodies. Examples of other ganglia: #1, #2 Parasympathetic Ganglion
Axons - light blue material at the center of each nerve fiber.
axons Peripheral Nerve
nuclei
brain nuclei
The outer wall of the esophagus (muscularis externa) is composed of two layers of muscle tissue.
Parasympathetic Ganglion
Lipofuscin - yellow-brown pigment located in the cytoplasm. It is end-stage lysosomes that accumulates with age.
Sympathetic Ganglia
Nerve cells of the sympathetic division of the autonomic nervous system are located in chains of ganglia on either side of the vertebral column. Ganglion Cells - large, nerve cell bodies with prominent nuclei and nucleoli.Nuclei - usually eccentrically located. Nissl Substance - abundant in the cytoplasm.Lipofuscin - yellow-brown pigment located in the cytoplasm. It is end-stage lysosomes that accumulates with age. Satellite (or Capsule) Cells - glial cells with small nuclei at the periphery of nerve cell bodies. Nerves - individual nerve fibers are difficult to identify because most are small unmyelinated or only lightly myelinated axons. This is in contrast to the larger, myelinated axons from the dorsal root ganglion. Schwann Cells - glial cells that wrap unmyelinated axons in cytoplasmic folds of a single Schwann cell. Their large, round nuclei are adjacent to some axons. Fibroblasts - elongated nuclei between axons. (Most frequent nuclei seen in nerves.) Connective Tissue - the ganglion is enclosed by a capsule of dense irregular connective tissue. Blood vessels are also seen within the ganglion
Sympathetic Ganglia
Nuclei - usually eccentrically located.
Sympathetic Ganglia
Satellite (or Capsule) Cells - glial cells with small nuclei at the periphery of nerve cell bodies.
Sympathetic Ganglia
Sympathetic Ganglia Blood Vessel
Sympathetic Ganglia
Sympathetic Ganglia capsule
Sympathetic Ganglia
Sympathetic Ganglion (left,
Sympathetic Ganglia
right Sympathetic Ganglion
Sympathetic Ganglia
