Human Tissue Structure and Function PDF

โครงสร้างและหน้าทีข่ องเซลล์และเนื้อเยื่อของมนุษย์ Structure and function of cells and tissues of the human Athipat Ngernmuen, Ph.D. 01416125 Human embryonic development and genetics 1 เซลล์ เนื้อเยื่อ และอวัยวะ เซลล์ (cell) คื...

โครงสร้างและหน้าทีข่ องเซลล์และเนื้อเยื่อของมนุษย์ Structure and function of cells and tissues of the human Athipat Ngernmuen, Ph.D. 01416125 Human embryonic development and genetics 1 เซลล์ เนื้อเยื่อ และอวัยวะ เซลล์ (cell) คือหน่วยชีวิตที่เล็กที่สุดของสิ่งมีชีวิต เนื้อเยื่อ (tissue) คือเซลล์หลายเซลล์มารวมกันและมีหน้าที่เดียวกัน อวัยวะ (organ) คือ เนื้อเยื่อจานวนมากประกอบกันเป็นอวัยวะ ระบบ (system) คือ อวัยวะหลายๆ อวัยวะมารวมกัน แล้วทาหน้าที่ใน เรื่องเดียวกัน โดยช่วยเสริมกัน Stevens and Lowe, 2008 2 เนื้อเยื่อพื้นฐาน ในร่างกายของคนประกอบด้วยเนื้อเยื่อพื้นฐาน 4 ชนิด คือ 1) เนื้อเยื่อบุผิว (epithelial tissue หรือ epithelium) 2) เนื้อเยื่อประสาน (connective tissue) เช่น กระดูกอ่อน (cartilage) กระดูก (bone) เลือด (blood) Stevens and Lowe, 2008 Stevens and Lowe, 2008 3) เนื้อเยื่อกล้ามเนื้อ (muscular tissue) 4) เนื้อเยื่อประสาท (nervous tissue) Ovalle and Nahirney, 2013 3 Epithelium Epithelium covers nearly all body surfaces. Epithelium is an avascular tissue, which lacks a direct blood supply. Nutrients are delivered by diffusion from blood vessels in the neighboring connective tissue. Most epithelial tissues are renewed continuously. https://slideplayer.com/slide/9037197/ Epithelial tissue can exist as sheets of adjoining cells covering lining the body surface as glands, secretory organs derived from epithelial cells. 4 Epithelium Epithelium covers nearly all body surfaces. Epithelium is an avascular tissue, which lacks a direct blood supply. Nutrients are delivered by diffusion from blood vessels in the neighboring connective tissue. Most epithelial tissues are renewed continuously. https://antranik.org/detailed-features-of-epithelia/ Protection of the tissues that it covers or lines Transcellular transport of molecules across epithelial sheets Secretion of various substances by glands Absorption (e.g., intestinal tract and kidney tubules) Control of movement of ions and molecules via selective permeability Detection of sensations (e.g., taste, sight, hearing). 5 Classification of epithelium number of layers of cells shape of surface cells Gartner and Hiatt, 2011 6 Classification of epithelium 7 Cui, 2011 Epithelium: apical surface Apical surface (domain): Exposed to a luminal or external environment; site of primary function (absorption,protection, etc.). Microvilli : composed of actin microfilaments anchored to terminal web. Microvilli increase apical surface area to aid in absorption. Cilia : composed of microtubules, arise from basal bodies. Cilia aid in the transport of material across the surface of the epithelium. Stereocilia : unusually long microvilli that aid in absorption. Cilia Microvilli Cui, 2011 8 Epithelium: lateral surface Lateral surface (domain): Contains junctional complexes that connect cells to neighboring cells. Tight junctions (zonula occludens) : specialized membrane proteins between the apical and the lateral surfaces of the cell. Surround the apical borders and serve as impermeable barriers. Adhering junctions (zonula adherens) : beneath the tight junctions, form bandlike junctions, and link the cytoskeleton of one cell to neighboring cells. They provide mechanical stability of the cells. Desmosomes (macula adherens) : spotlike junctions, which assist in cell-to-cell attachment. Gap junctions : communicating junctions that permit passage of ions and small molecules between neighboring cells. 9 Cui, 2011; Gartner and Hiatt, 2011 Epithelium: basal surface Basal surface (domain): Contains junctional complexes and basement membrane. Basolateral folds may also be present. Hemidesmosome : a junction (one half of a desmosome) connecting cells to the underlying basement membrane. Basement membrane : consists of basal lamina and reticular lamina, which provide an underlying sheet for epithelial cells. Basolateral folds : corrugations of the cell membrane in the lateral and basal regions of the cell, which increase cell surface area and are involved with ion and fluid transport. Cui, 2011; Gartner and Hiatt, 2011 10 Origin of epithelium Most epithelia originate from ectoderm and endoderm, although mesoderm also gives rise to some epithelia. Ectoderm gives rise to the epidermis of the skin, lining of the mouth and nasal cavity, cornea, sweat and sebaceous glands, and mammary glands. Endoderm gives rise to the lining of the gastrointestinal and respiratory systems and to the glands of the gastrointestinal system. Mesoderm gives rise to the uriniferous tubules of the kidney, the lining of the reproductive and circulatory systems, and the lining of the body cavities. Cui, 2011 Cui, 2011 Cui, 2011 Tubule of the kidney Small intestine 11 Palms of the hand Gartner and Hiatt, 2011 Origin of epithelium https://s3.amazonaws.com/static.wd7.us/d/d4/Cell_differentiation.gif 12 Clinical correlation Cui, 2011 https://www.slideshare.net/vmshashi/pathology-of-copd 13 Skeletal system Skeletal system (ระบบโครงกระดูก) Bone (กระดูก) Cartilage (กระดูกอ่อน) Joint (ข้อต่อ) ้ Tendon (เอ็นกล้ามเนื อ) Ligament (เอ็นกระดูก) Axial skeleton (กระดูกแกน) Skull (กระโหลก) Vertebra (กระดูกสันหลัง) ่ Rib (กระดูกซีโครง) Sternum (กระดูกอก) https://www.carolina.com/knowledge/2020/07/28/skeletal-system Appendicular skeleton (กระดูกรยางค ์) 14  Skeletal system Skeletal system Bone (กระดู ก) Cartilage (กระดู กอ่อน) Joint (ข้อต่อ) ้ Tendon (เอ็นกล้ามเนื อ) Ligament (เอ็นกระดู ก) Joint (ข้อต่อ) ตำแหน่งของกระดูกอ่อน https://www.healthpages.org/wp-content/uploads/2012/05/joints-of-body.jpg https://www.nursingtimes.net/clinical-archive/orthopaedics/effects-of-bedrest-5-the-muscles-joints-and-mobility-18-03-2019/ https://www.pinterest.com/pin/344455071473088812/ 15 Early development of skeletal system At 18th days At 22nd days Origin Paraxial mesoderm vertebrae and ribs some bones of skull base Lateral plate mesoderm e.g. limbs and sternum, pelvic and shoulder girdles Neural crest cell e.g. skull : face, cranial vault At 24th days At 26th days 16 Early development of skeletal system At 26th days Somite > Dermatome > Myotome > Sclerotome At the end of fourth week, Sclerotome cells become polymorphous and form loosely organized tissue, called mesenchyme, or embryonic connective tissue 17 Early development of skeletal system Mesenchymal cells migrate and differentiate in many ways. They may become fibroblasts, chondroblasts, or osteoblasts (bone-forming cells). Pountos, 2016 Pacifici and Koyama, 2020 18 Early development of skeletal system The bone-forming capacity of mesenchyme is not restricted to cells of the sclerotome but occurs also in the parietal layer of the lateral plate mesoderm of the body wall. Neural crest cells in the head region also differentiate into mesenchyme and participate in formation of bones of the face and skull. He et al., 2022 https://www.frontiersin.org/files/Articles/821667/fcell-10-821667-HTML-r1/image_m/fcell-10-821667-g001.jpg 19 Bone structure Mescher, 2016 20 Bone structure Mescher, 2016 Tesler et al., 2007 21 Bone formation In some bones, such as the flat bones of the skull, mesenchyme in the dermis differentiates directly into bone, a process known as intramembranous ossification In most bones, however, including the base of the skull and the limbs, mesenchymal cells first give rise to hyaline cartilage models, which in turn become ossified by endochondral ossification https://quizlet.com/327409297/osteogenesis-bone-development-intramembranous-ossification-endochondral-ossification-diagram/ 22 Bone formation Membranous bone formation (intramembranous ossification) Osteoid (bone matrix) https://www.slideshare.net/ahoward/anatomy-and-phisology-pp 23 Bone formation Endochondral bone formation (endochondral ossification) Diaphysis Osteoblast replace https://mmegias.webs.uvigo.es/02-english/guiada_a_oseo.php Mescher, 2016 This process in the diaphysis forms the primary ossification center, beginning in many embryonic bones as early as the first trimester. Around the time of birth secondary ossification centers begin to develop by a similar process in the bone’s epiphyses. 24 Bone formation Endochondral bone formation (endochondral ossification) Mescher, 2016 https://open.oregonstate.education/aandp/chapter/6-4-bone-formation-and-development/ 25 Bone formation Woven Lamellar Safadi et al., 2009 Diagram of immature and mature bone. Immature (woven) bone displays a disorganized lamellar appearance because of the interlacing arrangement of collagen fibers. The cells (osteoblasts and osteocytes) tend to be randomly arranged, whereas the cells in the mature bone are organized in circular fashion that reflects the lamellar structure of the Haversian system. 26 Bone slide preparations Ground bone : matrix details (especially canaliculi) H&E staining : decalcified bone H = Hematoxylin (Basic dye) stains nucleus etc. E = Eosin (Acidic dye) stains cytoplasmic protein etc. 27 http://lecannabiculteur.free.fr/SITES/UNIV%20W.AUSTRALIA/mb140/CorePages/Bone/Bone.htm https://slidetodoc.com/supporting-connective-tissue-cartilage-bone-and-joints-bone/ The development of Skull Neurocranium Membranous neurocranium Cartilaginous neurocranium Viscerocranium Membranous viscerocranium Cartilaginous viscerocranium Neurocranium the bones of the cranium enclosing the brain (brain box) Membranous bone formation Endochondral bone formation Viscerocranium the bones of the facial skeleton 28 https://slidetodoc.com/bones-axial-skeleton-cranial-bones-facial-bones-cranial/ The development of Skull At 6th week At 7th week At 12th week At 20th week 29 The development of Skull Nasal bone = กระดูกสันจมูก Lacrimal bone = กระดูกข้ำงถุงนำ้ ตำ Hyoid bone = กระดูกโคนลิน้ Dorsal view of the chondrocranium or base of the skull These structures are derived from neural Bones that form rostral to the rostral half of the sella crest (blue) turcica arise from neural crest and constitute the Paraxial mesoderm (somites and prechordal (in front of the notochord] chondrocranium somitomeres) (red) [blue]. Lateral plate mesoderm (yellow) Those forming posterior to this landmark arise from paraxial mesoderm (chordal chondrocranium) [red]. 30 The development of Skull Ethmoid bone = กระดูกขือ่ จมูก Frontal bone = กระดูกหน้ำผำก Sphenoid bone = กระดูกรูปผีเสือ้ Parietal bone = กระดูกข้ำงศีรษะ Maxilla bone = กระดูกขำกรรไกรบน Temporal bone = กระดูกขมับ Mandible bone = กระดูกขำกรรไกรล่ำง Occipital bone = กระดูกท้ำยทอย Zygomatic bone = กระดูกโหนกแก้ม 31 Skull of newborn At birth, the flat bones of the skull are separated from each other by narrow seams of connective tissue, the sutures At points where more than two bones meet, sutures are wide and are called fontanelles The most prominent of these is the anterior fontanelle, which is found where the two parietal and two frontal bones meet. Sutures and fontanelles allow the bones of the skull to overlap (molding) during birth. In most cases, the anterior fontanelle closes by 18 months of age, and the posterior fontanelle closes by 1 to 2 months of age. 32 Craniosynostosis Important category of cranial abnormalities is caused by premature closure of one or more sutures. These abnormalities are collectively known as craniosynostosis Scaphocephaly Brachycephaly -the sagittal suture -the coronal suture 33  The development of vertebral column Cervical = กระดูกสันหลังส่วนคอ Thoracic = กระดูกสันหลังส่วนอก Lumbar = กระดูกสันหลังส่วนเอว 34 https://www.britannica.com/science/vertebral-column https://www.spineuniverse.com/anatomy/intervertebral-discs The development of vertebral column Vertebrae form from the sclerotome portions of the somites, which are derived from paraxial mesoderm. During the fourth week, sclerotome cells migrate around the spinal cord and notochord to merge with cells from the opposing somite on the other side of the neural tube. 35 The development of vertebral column sclerotomes are found in three main areas : notochord, surrounding the neural tube, and in the body wall. In a frontal section of a 4-week embryo, the sclerotomes appear as paired condensations of mesenchymal cells around the notochord Transverse section through a 4-week embryo frontal section Each sclerotome consists of loosely arranged cells cranially and densely packed cells caudally. 36 The development of vertebral column Some densely packed cells move cranially, opposite the center of the myotome, where they form the intervertebral (IV) disc The remaining densely packed cells fuse with the loosely arranged cells of the immediately caudal sclerotome to form the mesenchymal centrum, the primordium of a body of a vertebra. Thus, each centrum develops from two adjacent sclerotomes and becomes an intersegmental structure. Transverse section through a 4-week embryo frontal section 37 The development of vertebral column The spinal nerves now lie in close relationship to the IV discs, and the intersegmental arteries lie on each side of the vertebral bodies. In the thorax, the dorsal intersegmental arteries become the intercostal arteries Where it is surrounded by the developing vertebral bodies, the notochord degenerates and Transverse section through a 4-week embryo disappears. Between the vertebrae, the notochord expands to form the gelatinous center of the IV disc—the nucleus pulposus. This nucleus is later surrounded by circularly arranged fibers that form the anulus fibrosus. 38 The development of vertebral column 39  The development of appendicular skeleton The appendicular skeleton consists of the pectoral and pelvic girdles and limb bones. Pectoral girdle Pelvic girdle https://www.illustratedverdict.com/template-lower-limb-orthopedic Limb bones https://commons.wikimedia.org/wiki/File:Pectoral_girdle_front_diagram.svg https://byjus.com/neet/pelvic-girdle/ 40 The development of appendicular skeleton The appendicular skeleton consists of the pectoral and At 28 days pelvic girdles and limb bones. e.g. limb bones During the sixth week, the mesenchymal bone models in At 44 days the limbs undergo chondrification to form hyaline cartilage bone models At 48 days By 12 weeks, primary ossification centers have appeared in nearly all limb bones At 56 days Longitudinal sections through an upper limb bud of a embryo showing development of the cartilaginous bones. https://www.sciencedirect.com/science/article/abs/pii/S0018442X13000152 41 The development of cartilage Cartilage develops from mesenchyme during the fifth week. In areas where cartilage is to develop, the mesenchyme condenses to form chondrification centers. The mesenchymal cells differentiate into chondroblasts, which secrete collagenous fibrils and extracellular matrix. Subsequently, collagenous and or elastic fibers are deposited in the intercellular substance or matrix. Three types of cartilage are distinguished according to the type of matrix that is formed: Hyaline cartilage, the most widely distributed type (e.g., in synovial joints) Fibrocartilage (e.g., in intervertebral discs) https://www.pinterest.com/pin/380976449697953966/ Elastic cartilage (e.g., in auricles of the external ears) 42 Bone fracture healing Mescher, 2016 43 Classification of muscle These muscle cells are of two types—striated, which display alternating light and dark bands, and smooth, which lack such striations. There are two types of striated muscle: Skeletal, for voluntary movements, Cardiac, for pumping blood 44 Skeletal muscle dense connective tissue, the epimysium A single skeletal muscle (e.g., the biceps) is composed of numerous fascicles An individual muscle fiber contains many myofibrils, which, in turn, consist of an array of regularly organized thick and thin myofilaments, the contractile elements of the muscle. Thick myofilaments are composed of clusters of myosin molecules, and the thin myofilaments are predominantly actin molecules but contain some additional auxiliary molecules that are important for the contraction process. Longitudinally, the actin and myosin molecules form repeating units called sarcomeres Actin filaments are anchored at one end in the Z line. Myosin molecules lie parallel to the actin molecules and partially overlap the actin molecules that are attached to two adjacent Z lines. The region in which the myosin and actin overlap is designated the A band, and the region in which only actin molecules are present is designated the I band 45 Skeletal muscle Longitudinal section of striated muscle. H&E, 400x A single muscle fiber have many nuclei. Transverse section of skeletal muscle (tongue) H&E, 272 Cui, 2011 46 Skeletal muscle Cui, 2011 47 Neuromuscular junction Pawlina et al., 2016 Cui, 2011 Ach = Acetylcholine AChE = Acetylcholinesterase 48 Clinical correlation https://www.slideshare.net/vstogetherforever/mg-full Cui, 2011 49 Muscle spindle Muscle spindles (a type of stretch receptor) play an important role in the control of voluntary movement, constantly monitoring the length of each muscle and rate of change of that length. Each spindle contains 10 to 15 specialized muscle fiber (intrafusal fibers) innervated by sensory and motor nerve fiber and surrounded by a fluid-filled connective tissue capsule. Anchored at each end to connective tissue attached to ordinary muscle fibers (extrafusal fibers). Cui, 2011 Mescher, 2016 50 Cardiac muscle Cardiac muscle fibers split and branch repeatedly and join other muscle fibers end to end to form an anastomosing network of contractile tissues. In contrast to skeletal muscle, cardiac muscle fibers contract and relax spontaneously. The intercalated disks at the boundaries between Cui, 2011 fibers contain gap junctions, which permit electrical depolarization to move directly and rapidly from one myocyte to the next. Mescher, 2016 Each fiber has a single, centrally located nucleus. 51 Cardiac muscle Longitudinal section of cardiac muscle. H&E, 272x Transverse section of cardiac muscle, H&E, 272 Cui, 2011 52 Smooth muscle Smooth muscle is similar to skeletal and cardiac muscle in that contraction is produced by the interaction of actin and myosin filaments in the presence of Ca2+. However, there are many differences. Smooth muscle fibers are spindle shaped and have single, centrally placed nuclei. Smooth muscle lacks the striations observed in skeletal and cardiac muscle because the arrangement of the actin and myosin filaments is not as orderly. Smooth muscle is innervated by sympathetic and parasympathetic axons. Cui, 2011 53 Early development of muscular system At 18th days At 22nd days Skeletal muscle is derived from paraxial mesoderm, which forms somites from the occipital to the sacral regions and somitomeres in the head. Smooth muscle differentiates from visceral splanchnic mesoderm surrounding the gut and its derivatives and from ectoderm (pupillary, mammary gland, and sweat gland muscles). Cardiac muscle is derived from visceral splanchnic At 24th days At 26th days mesoderm surrounding the heart tube. 54 Development of skeletal muscle Cells in the upper region of the somite form the dermatome and two muscle-forming areas at the ventrolateral (VLL) and dorsomedial (DML) lips (or edges), respectively Cells from these two areas migrate and proliferate to form progenitor muscle cells ventral to the dermatome, thereby forming the dermomyotome 55 Development of skeletal muscle Some cells from the VLL region also migrate into the adjacent parietal layer of the lateral plate mesoderm Here they form infrahyoid, abdominal wall (rectus abdominus, internal and external oblique, and transversus abdominus), and limb muscles. The remaining cells in the myotome form muscles of the back, shoulder girdle, and intercostal muscles Initially, there is a well-defined border between each somite and the parietal layer of lateral plate mesoderm called the lateral somatic frontier 56 Development of skeletal muscle This frontier separates two mesodermal domains in the embryo: The primaxial domain that comprises the region around the neural tube and contains only somite- derived (paraxial mesoderm) cells. The abaxial domain that consists of the parietal layer of lateral plate mesoderm together with somite cells that have migrated across the lateral somitic frontier https://slideplayer.com/slide/8065002/ Muscle cells that cross this frontier (those from the VLL edge of the myotome) and enter the lateral plate mesoderm comprise the abaxial muscle cell precursors and receive many of their signals for differentiation from lateral plate mesoderm those that remain in the paraxial mesoderm and do not cross the frontier (the remaining VLL cells and all of the DML cells) comprise the primaxial muscle cell precursors and receive many of their developmental signals from the neural tube and notochord. 57 Development of skeletal muscle During embryonic muscle development, mesenchymal myoblasts fuse, forming myotubes with many nuclei. Myotubes then further differentiate to form striated muscle fibers. Elongated nuclei are found peripherally just under the sarcolemma, a characteristic nuclear location unique to skeletal muscle fibers/cells. Mescher, 2016 A small population of reserve progenitor cells called muscle satellite cells remains adjacent to most fibers of differentiated skeletal muscle. 58 Development of skeletal muscle https://www.pinterest.com/pin/824932856722480004/ 59 Development of skeletal muscle Regardless of their domain, each myotome receives its innervation from spinal nerves derived from the same segment as the muscle cells. 60 Innervation of skeletal muscle Each developing spinal nerve also divides and sends a branch to each division, with the dorsal primary ramus supplying the epaxial division and the ventral primary ramus supplying the hypaxial division. Some muscles, such as the intercostal muscles, remain segmentally arranged like the somites. most myoblasts migrate away from the myotome and form nonsegmented muscles. Epaxial (above the axis) muscles (back muscles) are innervated by dorsal primary rami, whereas hypaxial (below the axis) muscles (body wall and limb muscles) are innervated by ventral primary rami. https://www.rehabmypatient.com/ribs/intercostals 61 Head musculature All voluntary muscles of the head region are derived from paraxial mesoderm (somitomeres and somites), including musculature of the tongue, eye (except that of the iris, which is derived from optic cup ectoderm), and that associated with the pharyngeal (visceral) arches. At 7th week https://radiologykey.com/embryology-anatomy-normal-findings-and-imaging-techniques-3/ The paraxial mesoderm forms the somitomeres and somites. 62 Limb musculature The first indication of limb musculature is observed in the seventh week of development as a condensation of mesenchyme near the base of the limb buds. The mesenchyme is derived from dorsolateral cells of the somites that migrate into the limb bud to form the muscles. With elongation of the limb buds, the muscle tissue first splits into flexor and At 7th week extensor components At 48 days At 51 days At 56 days 63 Development of smooth muscle Smooth muscle differentiates from visceral splanchnic mesoderm surrounding the gut and its derivatives The smooth muscle in the walls of many blood and lymphatic vessels arises from the somatic mesoderm. The muscles of the iris (sphincter and dilator pupillae) and the myoepithelial cells in the mammary and sweat glands are believed to be derived from mesenchymal cells that originate from ectoderm. 64 Development of cardiac muscle Webster and de Wreede, 2016 Cardiac muscle cells are also derived from splanchnic mesoderm surrounding the early heart tube. The cardiac myoblasts differ from skeletal myoblasts in that they do not fuse to form multinucleated fibers, and they remain individual but connected via intercalated discs 65 Development of cardiac muscle The lateral splanchnic mesoderm gives rise to the mesenchyme surrounding the developing heart tube. At 22nd days At 28th days 66 Blood The blood is a mixture of cellular elements, fluid, proteins and metabolites. Blood is a specialized connective tissue consisting of cells and fluid extracellular material. The so-called formed elements circulating in the plasma are erythrocytes (red blood cells), leukocytes (white blood cells), and platelets. Blood has four major elements: Red blood cells (erythrocytes) transport oxygen from the lungs to the peripheral tissues White blood cells (leukocytes) have a defensive role, destroying infecting organisms, such as bacteria and viruses, as well as assisting in the removal of dead or damaged tissues Platelets (thrombocytes) are the first line of defence against damage to blood vessels, adhering to defects and participating in the blood clotting system Plasma is the proteinaceous solution in which the above-mentioned cells circulate, and carries nutrients, metabolites, antibodies, hormones, proteins https://openmd.com/guide/blood-components of the blood clotting system and other molecules throughout the body 67 Blood In postnatal life, under normal circumstances, the formation of the cellular elements of the blood (haemopoiesis) occurs in the bone marrow in various bones. Most of the proteins in the plasma are made by the liver. Stevens and Lowe, 2008 https://www.beckman.jp/resources/sample-type/tissues/bone-marrow Bone marrow is found in the medullary canals of long bones and in the small cavities of cancellous bone, with two types based on their appearance at gross examination: blood-forming red bone marrow, whose color is produced by an abundance of blood and hemopoietic cells, and yellow bone marrow, which is filled with adipocytes that exclude most hemopoietic cells. In the newborn all bone marrow is red and active in blood cell production, but as the child grows, most of the marrow changes gradually to the yellow variety. 68 Hematopoiesis In postnatal life, under normal circumstances, the formation of the cellular elements of the blood (haemopoiesis) occurs in the bone marrow in various bones. Most of the proteins in the plasma are made by the liver. All blood cells arise from a single type of pluripotent hemopoietic stem cell in the bone marrow that can give rise to all the blood cell types. Two major lineages of progenitor cells : one for lymphoid cells (lymphocytes) and another for myeloid cells that develop in bone marrow. Myeloid cells include granulocytes, monocytes, erythrocytes, and megakaryocytes. The lymphoid progenitor cells migrate from the bone marrow to the thymus or the lymph nodes, https://microbenotes.com/hematopoiesis/ spleen, and other lymphoid structures, where they proliferate and differentiate. 69 Hematopoiesis https://en.wikipedia.org/wiki/Haematopoiesis#/media/File:Hematopoesis_EN.svg Mature blood cells have a relatively short life span and must be continuously replaced with new cells from precursors developing during hemopoiesis (Gr. haima, blood + poiesis, a Mescher, 2016 making). In the early embryo these blood cells arise in the yolk sac mesoderm. In the second trimester, hemopoiesis (also called hematopoiesis) occurs primarily in the developing liver, with the spleen playing a minor role. Skeletal elements begin to ossify and bone marrow develops in their medullary cavities, so that in the third trimester marrow of specific bones becomes the major hemopoietic organ. 70 Formed element Blood smear https://www.youtube.com/watch?v=KSs0SMfERuA Mescher, 2016 71 Formed element https://www.medical-labs.net/normal-blood-smear-649/ https://www.austincc.edu/apreview/PhysText/Blood.htm 72 Red blood cell The red blood cells are responsible for oxygen transport. Red cells in peripheral blood smears appear as rounded, bright pink-stained cells. They are 6.5–8.5 µm in diameter and have a biconcave shape, appearing paler in the centre and darker at the periphery 73 White blood cell White cells use the blood for transport from the bone marrow to their major sites of activity. There are five types of white cells, and their names and relative proportions in the circulation are as follows: Neutrophils 40–75% Eosinophils 5% Basophils 0.5% Lymphocytes 20–50% Monocytes 1–5%. Neutrophils, eosinophils and basophils are known as granulocytes because their cytoplasm contains prominent granules Lymphocytes and monocytes are classed as white blood cells because they are a constituent of the blood and ultimately originate from bone marrow. They are found mainly in tissues such as lymph nodes and spleen. In the tissues, monocytes transform into macrophages. Monocytes respond chemotactically to the presence of necrotic material, invading microorganisms and inflammation, and leave the blood to enter the tissues, where they are called macrophages. 74 White blood cell Neutrophils Neutrophils Basophils Nucleus: 3-5 lobes Nucleus: Bilobed Nucleus: Bilobed or S-shaped Granules: faint/light pink Granules: Red/dark pink Granules: Dark blue/purple Function: Kill and phagocytose bacteria Function: Kill helminthic and other Function: Modulate inflammation, parasites; modulate local inflammation release histamine during allergy Lymphocytes Monocytes Nucleus: Rather spherical Nucleus: Indented or C-shaped Granules: (none) Granules: (none) Function: Effector and regulatory cells Function: Precursors of macrophages for adaptive immunity 75 Platelet Platelets are small cell fragments derived from megakaryocytes and are important in hemostasis. Platelets (also called ‘thrombocytes’) are small, disc-shaped anuclear structures that are formed by the cytoplasmic fragmentation of huge precursor cells (megakaryocytes) in the bone marrow. Young et al., 2014 76 Hemostasis https://samarpanphysioclinic.com/physiology-blood-clotting-mechanism-coagulation/ Young et al., 2014 Hemostasis is the reaction to an injury that causes bleeding to stop bleeding and to repairs on the injury. 77 Blood group https://mysciencesquad.weebly.com/ib-hl-34a1.html 78 Hemocrit https://www.healthyandnaturalworld.com/hematocrit-hct-blood-test/ Collected blood in which clotting is prevented by the addition of anticoagulants (eg, heparin or citrate) can be separated by centrifugation into layers that reflect its heterogeneity. Erythrocytes comprise the sedimented material and their volume, normally about https://www.brainkart.com/article/Diagnostic-Blood-Tests_21873/ 44% of the total blood volume in healthy adults, is called the hematocrit 79 Clinical correlations Anaemia = โลหิตจาง Stevens and Lowe, 2005 80 Clinical correlations https://my.clevelandclinic.org/health/diseases/21053-rh-factor Small amounts of fetal blood may pass to the maternal blood through microscopic breaks in the placental membrane. https://twitter.com/jimmunoallerg/status/1471341617617334272 If the fetus is Rh-positive and the mother is Rh-negative, the fetal cells may stimulate the formation of anti-Rh antibody by the mother’s immune system. Erythroblastosis fetalis This antibody passes to the fetal blood and causes hemolysis of fetal Rh-positive blood cells and anemia in the fetus. 81 Nervous system The nervous system allows rapid and specific communication between widely spaced areas of the body by the action of specialized nerve cells (neurons), which gather and process information and generate appropriate response signals. https://knowledge.carolina.com/discipline/life-science/anatomy-and-physiology/nervous-system/ 82 Nervous system The nervous system is divided into two main parts: The central nervous system (CNS) comprising the brain and spinal cord The peripheral nervous system (PNS) comprising the nerves which run between the CNS and other tissues, together with nerve ‘relay stations’ termed ‘ganglia’ Cranial nerve (เส้นประสาทสมอง) มี 12 คู่ Spinal nerve (เส้นประสาทไขสันหลัง) มี 31 คู่ The autonomic nervous system (ANS) Sympathetic nervous system https://pressbooks.ccconline.org/bio106/chapter/nervous-system-levels-of-organization/ Parasympathetic nervous system 83 Autonomic nervous system Sympathetic nervous system - Thorax and Lumbar regions - Sympathetic ganglia อยู่ห่างจากอวัยวะที่จะไปสั่งการ Parasympathetic nervous system - Midbrain, Pons, Medulla oblongata and Sacral region https://imotions.com/blog/learning/research-fundamentals/nervous-system/ 84 Development of nervous system The first indications of the development of the nervous system appear during the third week as the neural plate and neural groove develop on the posterior aspect of the trilaminar embryo. The nervous system develops from the neural plate, a thickened area of embryonic ectoderm. The notochord and paraxial mesoderm induce the overlying ectoderm to differentiate into the neural plate. Formation of the neural folds, neural crest, and neural tube is illustrated. The neural tube differentiates into the CNS, consisting of the brain and spinal cord. The neural crest gives rise to cells that form most of the PNS and ANS. Neurulation—formation of the neural plate and neural tube—begins during the fourth week (22–23 days) in the region of the fourth to sixth pairs of somites 85 Moore et al., 2016 Development of nervous system Gartner et al., 2011 86 Nervous cell Neurons are characterized by: A cell body containing the nucleus and most of the organelles responsible for maintaining the cell A long cell process (axon) stretching from the cell, often over a long distance, which is responsible for transmitting signals from the neuron to other cells Numerous short cell processes (dendrites) which increase the surface area available for connecting with axons of other neurons Mescher, 2016 Specialized cell junctions (synapses) between it axon and other cells to allow direct cell communication 87 Nervous cell Micrograph showing a neuron with a large nucleus (N) containing a prominent nucleolus. Within the cell body, blue-staining Nissl substance (Ns), composed of rough endoplasmic reticulum, can be seen. The axon (A) stretches away from the cell body Young et al., 2014 The diagram illustrates the main ultrastructural features of the neurone, in this case a multipolar neurone with an axon and two dendrites. The nucleus is large, round or ovoid and usually centrally located within the perikaryon. Reflecting the intense metabolic activity of the neurone (and consequent need to replace proteins which are rapidly turned over), the chromatin is completely dispersed and the nucleolus is a conspicuous feature. Stevens and Lowe, 2005 88 Glial cells Glial cells support neuronal survival and activities, and are ten times more abundant than neurons in the mammalian brain. Like neurons most glial cells develop from progenitor cells of the embryonic neural plate. Mescher, 2016 89 Type of nervous cell Multipolar neurons, each with one axon and two or more dendrites, are the most common. Bipolar neurons, with one dendrite and one axon, comprise the sensory neurons of the retina, the olfactory epithelium, and the inner ear. Pseudounipolar neurons possess a single process that extends from the cell body and subsequently branches into an axon and dendrite. They are present in spinal and cranial https://qbi.uq.edu.au/brain/brain-anatomy/types-neurons ganglia. Unipolar neurons: only one process that extend from cell body. 90 Type of nervous cell Unique Purkinje neurons characterize the cortex of the cerebellum, and layers of small pyramidal neurons form the cerebral cortex Gartner et al., 2011 91 Type of nervous cell Pyramidal neurons Ovalle et al., 2013 92 Type of nervous cell Purkinje neurons Ovalle et al., 2013 93 Type of nervous cell https://www.toppr.com/ask/content/story/amp/difference-between-sensory-motor-and-associated-neuron-56465/ https://online-learning-college.com/knowledge-hub/gcses/gcse-biology-help/neurons-central-nervous-system/ Sensory or afferent neurons are afferent, receiving stimuli from receptors throughout the body. Motor or efferent neuron :are efferent, sending impulses to effector organs such as muscle fibers and glands Association neuron or interneuron : establish relationships among other neurons, forming complex functional networks or circuits in the CNS. 94 Type of nervous cell https://mammothmemory.net/biology/coordination-and-response/nerves/three-types-of-neurone.html Axon ยำว ส่วนใหญ่ Multipolar neuron Axon สั้น Cell body อยู่ปลำย Cell body อยู่ด้ำนข้ำง Dendrites สั้น มีหลำย dendrites ส่วนใหญ่ Pseudounipolar neuron ส่วนใหญ่ Multipolar neuron 95 Ganglion Ganglia are typically ovoid structures containing neuronal cell bodies and their surrounding glial satellite cells supported by delicate connective tissue and surrounded by a denser capsule. Because they serve as relay stations to transmit nerve impulses, at least one nerve enters and another exits from each ganglion. The direction of the nerve impulse determines whether the ganglion will be a sensory or an autonomic ganglion. Motor ganglion https://www.instantanatomy.net/podcasts/IA132.pdf http://easydoc.in.th 96 Ganglion Sensory ganglion http://easydoc.in.th Young et al., 2006 97 Ganglion Sympathetic ganglion https://cmconnect.cmcc.edu/ICS/icsfs/Chapter_14.pdf?target=d719d48a-4ded-4ae9-90e0-b916d995a349 98 Ganglion Parasympathetic ganglion https://cmconnect.cmcc.edu/ICS/icsfs/Chapter_14.pdf?target=d719d48a-4ded-4ae9-90e0-b916d995a349 99 Nerve ending https://pressbooks.ccconline.org/bio106/chapter/nervous-sensory-functions/ 100 Brain The major structures comprising the CNS are the cerebrum, cerebellum, and spinal cord. The CNS is completely covered by connective tissue layers, the meninges, but CNS tissue contains very little collagen or similar material, making it relatively soft and easily damaged by injuries affecting the protective skull or vertebral bones. Many structural features of CNS tissues can be seen in unstained, freshly dissected specimens. Many regions show organized areas of white matter and gray matter, differences caused by the differential distribution of lipid- rich myelin. The main components of white matter are myelinated axons Gray matter contains abundant neuronal cell bodies, dendrites, astrocytes, and microglial cells, and is where most synapses occur. https://my.clevelandclinic.org/health/articles/23073-cerebral-cortex 101 Spinal cord In cross sections of the spinal cord the white matter is peripheral and the gray matter forms a deeper, H-shaped mass. The two anterior projections of this gray matter, the anterior horns, contain cell bodies of very large motor neurons whose axons make up the ventral roots of spinal nerves. The two posterior horns contain interneurons which receive sensory fibers from neurons in the spinal (dorsal root) Mescher 2016 ganglia. Dorsal root Near the middle of the cord the gray matter surrounds a small Dorsal root ganglion central canal, which develops from the lumen of the neural tube, is continuous with the ventricles of the brain, is lined by ependymal cells, and contains CSF (Cerebrospinal fluid). https://quizlet.com/200552568/exam-2-chapter-13-spinal-cord-diagram-labeling-flash-cards/ 102 103