Glossary
Anencephaly: A type of birth defect in which most of the brain is missing
Anomalies: Defects; abnormal processes that occur during development
Apical ectodermal ridge: Thickening of the ectoderm in the distal limb bud tip
Apoptosis: A programmed cell death
Arteries: A blood vessels that carries blood away from the heart
Autosomal: Pertaining to chromosome that is not a sex chromosome
Branchial arches: The successive bulges in the lateral walls of the pharynx found between successive branchial groove and branchial pouches or both
Bone marrow: Blood forming tissues found within certain bones
Calvarium: The flat bones of the skull collectively, which makes up the cranial vault containing the brain
Caudal: Toward the tail end, inferior
Centrum: The premodium of the body of the vertebral column
Cephalic: Toward the head, superior, cranial
Chondrification: The process of converting or changing tissue into cartilage
Chodrogenesis, Formation of cartilage
Chondrocranium: The anterior part of the axial skeleton that encases the special sense organs and contributes to the skeletal elements encasing the brain
Chondrocyte: A mature cartilage cell derived from the mesodermal mesenchyme Chondrogenesis A process of formation of the cartilage
Cranial vault see the calvarium
Defects see anamolies
Dermomyotome: Portion of the somites which form the dermis of the skin and skeletal muscles
Dermatome: Portion of the somite that form the dermis of the skin of the back
Dermis The inner part of the skin, derived from the mesoderm
Diaphysis: The shaft (middle) of the long bone
Differentiation: Specialization of the cells or group of cells
Digit: A finger or toe
Dysplasia: Enlargement of cells or tissues by proliferation of cells of abnormal type
Ectoderm: The outer of the three primary germ layers, which forms the nervous system and the epidermis of the skin
Embryo: The fertilized ovum until the end of week 8
Embryonic period: The first 8 weeks of human development, during which the developing organism does not resemble human
Endochondral ossification: Ossification that occurs within cartilage
Epiphysis: The end of the long bone
Extremities: The limb
Fetus: The embryo from the beginning of week 9 to birth
Fetal period: The period of development from week 8 to birth
Fontanelles: Temporary openings between bony plates of the skull, formed during the formation and fusion of the cranial bones
Footplate: The primodium of the foot
Foramen magnum: The largest opening of the skull through which the spinal cord descend down
Gestation: Pregnancy
Germ layers: The three cellular germ layers resulting from gastrulatio
Growth: An increase in size
Hand plate: The primodium of the hand
Histogenesis: The process of formation of the tissues
Hyaline cartilage: Cartilage with a clear translucent matrix, found primarily on the ends of ribs and on the trachea
Hypertrophy: An increase in cell size
Induction: Phenomenon wherein, one part of the embryo determines the fate of another part
Intervertebral foramen: Opening between the vertebrae through which the spinal nerves passed
Intervertebral disc: Is the soft tissue found between successive vertebrae in the vertebral column
Intramembranous Ossification: Ossification that occurs within condensed mesenchyme, usually in the flat bones of the skull
Joint: Union between two bones
Lateral mesoderm: Part of the mesoderm found bilaterally lateral to the intermediate mesoderm
Limb bud: The first indications of the developing limbs, bilaterally on the side of the embryo
Limbs: Arms and legs
Mandible: The lower jaw
Mandibular arch: The first pair of branchial (pharyngeal) arches, which give rise to lower and upper jaws
Mandibular process: The part of the first arch which forms the mandible
Maxilla: The upper jaw
Maxillary process: The part of the first arch which forms the maxilla, zygomatic and temporal squamous
Mesenchymal cells: The cells that make up part of the mesenchyme
Mesenchyme: A loosely arranged type of embryonic tissue, which can differentiate into much type of cells
Mesoderm: The middle of the three primary germ layers, which forms muscles, connective tissue and several other tissue within the embryo
Mitosis: A type of cell divisions undergone by eukaryotic cells, which is vital for the growth and maintenance of the organism.
Morphogenesis: Is the process during development that gives rise to form or shape of the organism or structure
Myoblast: The precursors cells of the muscle fibers
Myotome: A portion of each somite that gives rise to muscles
Neonate: An infacnt
Nerve: A group of nerve cell processes contain within a single sheath
Neural crest: A group of cell dorsal to the neural tube which form most of the PNS, pigment cells, meninges and several other tissue
Neural tube: Is a tubular precursors of the CNS, derived from the ectoderm
Neurocranium: Portion of the cranium that houses the brain
Neuropores: Opening at both ends of the newly formed neural tube, which close later in development
Notochord: A dorsal rod of mesoderm which gives some structural support to the early embryo, and is replaced by vertebral column and only gives rise to nuclei pulposi of the intervertebral discs of the adult.
Nucleus pulposis: The center of the intervertebral disc derived from the notochord
Ossicles: Small bones of the middle ear, such as malleus, incus and stapes
Ossification: The process of bone formation
Ossification centers: A region from which bone formation spread outward.
Osteoblasts: Cells derived from the mesenchyme cells which are the precursors of the osteocytes and are responsible for bone deposition
Osteoclasts: Cells that have ability to break down already formed bone
Osteocytes: Bone forming cells, derived from osteoblasts
Osteogenesis: The process of bone formation
Paraxial mesoderm: The portion of mesoderm which bilaterally flanks the embryonic axis and gives to somites
Perichondrium: The connective tissue covering of the cartilage
Periosteum: The connective tissue covering the bone
Pituitary gland: An endocrine gland derived
Posterior: Nearer the back of the body, dorsal
Proliferation: An increase in cell number by cell division
Rostral: The relationship of a structure to the head
Sclerotome: The portion of the somites that gives rise to the vertebrae of the vertebral column
Skull:The skeleton of the head
Somatic mesoderm: Dorsal layer of the mesoderm derived from the lateral mesoderm
Somites: segmental blocks of paraxial mesoderm
Spinal cord: A portion of CNS derived from the caudal portion of the neural tube
Sutures: The narrow spaces between the bony plates of the skull, which are most conspious at about the time of birth
Unilateral: One side only,
Vertebrae: The element of the vertebral column (backbone)
Vertebral column: (back bone) A portion of the axial skeleton derived from the scleretome and responsible for bony protection of the spinal cord
Viscerocranium A portion of cranium that surrounds the oral cavity, pharynx and upper respiratory system
Anencephaly: A type of birth defect in which most of the brain is missing
Anomalies: Defects; abnormal processes that occur during development
Apical ectodermal ridge: Thickening of the ectoderm in the distal limb bud tip
Apoptosis: A programmed cell death
Arteries: A blood vessels that carries blood away from the heart
Autosomal: Pertaining to chromosome that is not a sex chromosome
Branchial arches: The successive bulges in the lateral walls of the pharynx found between successive branchial groove and branchial pouches or both
Bone marrow: Blood forming tissues found within certain bones
Calvarium: The flat bones of the skull collectively, which makes up the cranial vault containing the brain
Caudal: Toward the tail end, inferior
Centrum: The premodium of the body of the vertebral column
Cephalic: Toward the head, superior, cranial
Chondrification: The process of converting or changing tissue into cartilage
Chodrogenesis, Formation of cartilage
Chondrocranium: The anterior part of the axial skeleton that encases the special sense organs and contributes to the skeletal elements encasing the brain
Chondrocyte: A mature cartilage cell derived from the mesodermal mesenchyme Chondrogenesis A process of formation of the cartilage
Cranial vault see the calvarium
Defects see anamolies
Dermomyotome: Portion of the somites which form the dermis of the skin and skeletal muscles
Dermatome: Portion of the somite that form the dermis of the skin of the back
Dermis The inner part of the skin, derived from the mesoderm
Diaphysis: The shaft (middle) of the long bone
Differentiation: Specialization of the cells or group of cells
Digit: A finger or toe
Dysplasia: Enlargement of cells or tissues by proliferation of cells of abnormal type
Ectoderm: The outer of the three primary germ layers, which forms the nervous system and the epidermis of the skin
Embryo: The fertilized ovum until the end of week 8
Embryonic period: The first 8 weeks of human development, during which the developing organism does not resemble human
Endochondral ossification: Ossification that occurs within cartilage
Epiphysis: The end of the long bone
Extremities: The limb
Fetus: The embryo from the beginning of week 9 to birth
Fetal period: The period of development from week 8 to birth
Fontanelles: Temporary openings between bony plates of the skull, formed during the formation and fusion of the cranial bones
Footplate: The primodium of the foot
Foramen magnum: The largest opening of the skull through which the spinal cord descend down
Gestation: Pregnancy
Germ layers: The three cellular germ layers resulting from gastrulatio
Growth: An increase in size
Hand plate: The primodium of the hand
Histogenesis: The process of formation of the tissues
Hyaline cartilage: Cartilage with a clear translucent matrix, found primarily on the ends of ribs and on the trachea
Hypertrophy: An increase in cell size
Induction: Phenomenon wherein, one part of the embryo determines the fate of another part
Intervertebral foramen: Opening between the vertebrae through which the spinal nerves passed
Intervertebral disc: Is the soft tissue found between successive vertebrae in the vertebral column
Intramembranous Ossification: Ossification that occurs within condensed mesenchyme, usually in the flat bones of the skull
Joint: Union between two bones
Lateral mesoderm: Part of the mesoderm found bilaterally lateral to the intermediate mesoderm
Limb bud: The first indications of the developing limbs, bilaterally on the side of the embryo
Limbs: Arms and legs
Mandible: The lower jaw
Mandibular arch: The first pair of branchial (pharyngeal) arches, which give rise to lower and upper jaws
Mandibular process: The part of the first arch which forms the mandible
Maxilla: The upper jaw
Maxillary process: The part of the first arch which forms the maxilla, zygomatic and temporal squamous
Mesenchymal cells: The cells that make up part of the mesenchyme
Mesenchyme: A loosely arranged type of embryonic tissue, which can differentiate into much type of cells
Mesoderm: The middle of the three primary germ layers, which forms muscles, connective tissue and several other tissue within the embryo
Mitosis: A type of cell divisions undergone by eukaryotic cells, which is vital for the growth and maintenance of the organism.
Morphogenesis: Is the process during development that gives rise to form or shape of the organism or structure
Myoblast: The precursors cells of the muscle fibers
Myotome: A portion of each somite that gives rise to muscles
Neonate: An infacnt
Nerve: A group of nerve cell processes contain within a single sheath
Neural crest: A group of cell dorsal to the neural tube which form most of the PNS, pigment cells, meninges and several other tissue
Neural tube: Is a tubular precursors of the CNS, derived from the ectoderm
Neurocranium: Portion of the cranium that houses the brain
Neuropores: Opening at both ends of the newly formed neural tube, which close later in development
Notochord: A dorsal rod of mesoderm which gives some structural support to the early embryo, and is replaced by vertebral column and only gives rise to nuclei pulposi of the intervertebral discs of the adult.
Nucleus pulposis: The center of the intervertebral disc derived from the notochord
Ossicles: Small bones of the middle ear, such as malleus, incus and stapes
Ossification: The process of bone formation
Ossification centers: A region from which bone formation spread outward.
Osteoblasts: Cells derived from the mesenchyme cells which are the precursors of the osteocytes and are responsible for bone deposition
Osteoclasts: Cells that have ability to break down already formed bone
Osteocytes: Bone forming cells, derived from osteoblasts
Osteogenesis: The process of bone formation
Paraxial mesoderm: The portion of mesoderm which bilaterally flanks the embryonic axis and gives to somites
Perichondrium: The connective tissue covering of the cartilage
Periosteum: The connective tissue covering the bone
Pituitary gland: An endocrine gland derived
Posterior: Nearer the back of the body, dorsal
Proliferation: An increase in cell number by cell division
Rostral: The relationship of a structure to the head
Sclerotome: The portion of the somites that gives rise to the vertebrae of the vertebral column
Skull:The skeleton of the head
Somatic mesoderm: Dorsal layer of the mesoderm derived from the lateral mesoderm
Somites: segmental blocks of paraxial mesoderm
Spinal cord: A portion of CNS derived from the caudal portion of the neural tube
Sutures: The narrow spaces between the bony plates of the skull, which are most conspious at about the time of birth
Unilateral: One side only,
Vertebrae: The element of the vertebral column (backbone)
Vertebral column: (back bone) A portion of the axial skeleton derived from the scleretome and responsible for bony protection of the spinal cord
Viscerocranium A portion of cranium that surrounds the oral cavity, pharynx and upper respiratory system
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(Copyright © 2011 by U. Bala)