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Text and images
© Jeremy Cook 1997–2008





New in version 3.41 (May 2011)

Version 3.41 has exactly the same learning content as 2.41 but it has been adapted and recompiled to run under the latest version of ToolBook (10.5).

This makes it compatible with the most recent Microsoft Windows operating systems, including 64-bit Windows 7, which is increasingly being marketed to the public as a general-purpose operating system, despite not being backwards-compatible with much classic Windows software.


New in Versions 2.40/2.41:-

  • Gametogenesis, fertilization and the early embryo
    Revisions to main pages, more-boxes, glossary entries and references on oogenesis and spermatogenesis, fertilization, the blastocyst, implantation and body axis determination, the germ-line, conception and contraception, and monozygotic twinning.
            Includes new laparoscopic images of spontaneous human ovulation, and new notes and/or references on protamines, sperm chemotaxis, meiotic arrest, sperm–egg interaction, mucus and fertility, implantation mechanisms and signalling, inner cell mass differentiation, the role of nodal cilia in determining body axis asymmetry, genomic imprinting, primordial germ cell induction and migration, pluripotency and embryonic stem cells, X-inactivation, senescence and the control of telomere length, monozygotic twin differences and the embryo in UK law.
  • Shared events – the primitive cloaca and urogenital ducts
    Revisions and new references in respect of paramesonephric duct formation.
  • Development by region and system
    New notes and/or references in respect of branching morphogenesis, lung problems in renal agenesis, vascular patterning and the roles of Hox genes.
  • Topic overviews – the embryology of speech and hearing
    New pages, images, More-boxes, glossary entries, references and additional material for lip, gum and tooth development.
  • Preimplantation genetic diagnosis
    A revision by Professor Joy Delhanty, including new diagnostic capabilities and new references to age-related aneuploidy, senescence, the control of telomere length and PGD review articles.

New in Version 2.3:-

  • Development by region and system : the developing nervous system
    The basics of neurulation; Cell division and migration; Alar and basal plates; Spinal ganglia; Spinal roots and nerves; Autonomic neurons; Cranial ganglia; Coverings of the brain and spinal cord; Brain regionalization and folding; Anomalies of the nervous system.
    Plus minor enhancements and research updates in many other sections.

New in Version 2.2:-

  • Development by region and system : the developing special sense organs
    The olfactory neurons and nerve; The optic vesicle and cup; The lens placode, pit and vesicle; The ciliary body, iris, outer coats etc.; The developing neural retina; Anomalies of eye development; The developing inner ear; The middle ear and auditory tube; The outer ear; Anomalies of the ear.
  • Development by region and system : the developing cardiovascular system
    The primitive cardiovascular system; Embryonic vascular templates; The early embryonic heart; Division of the atrioventricular canal; Septation of the primitive atrium; Septation of the ventricle and outflow tract; remodelling of the venous system; Lymphatics; Vascular anomalies; The circulation in the fetus and at birth.

New in Version 2.1:-

  • Shared events that span systems : the primitive cloaca and urogenital ducts
    Making sense of the cloaca; The cloacal plate and urorectal septum; The urogenital and anal membranes; The mesonephros and its ducts; The paramesonephric ducts; Anomalies of the cloaca and ducts.
  • Development by region and system : the developing digestive system Origins of the primitive gut; Development of the foregut; The liver and biliary system; The pancreas and spleen; Foregut anomalies; Development of the midgut; Midgut anomalies; Development of the hindgut; Hindgut anomalies.
  • Development by region and system : the developing excretory system Links to ‘Cloaca and ducts’; Formation of the ureteric ducts; The metanephric cap and its role; Branching of the ureteric buds; Ascent of the metanephric kidneys; The developing urinary bladder; Anomalies of the excretory system.
  • Development by region and system : the developing reproductive system Links to ‘Germ Line’; Links to ‘Cloaca and ducts’; Summary of the two duct systems; Duct/gonad interactions in the male; Duct/gonad interactions in the female; Shaping the external genitalia; The gubernaculum and peritoneum; Anomalies of the reproductive system.

New in Version 2.0:-

‘Topic overviews in development’
A new, fourth entry under this heading integrates several topics of particular interest to students of Speech and Language Therapy.

  • Parts of speech: the embryology of speech and hearing Making sense of the embryonic head; The pharynx in the early embryo; The tongue and the thyroid gland; The respiratory tract; The pouches, arteries and cartilages; The larynx; The salivary glands; The pharyngeal clefts; The face, nasal cavities and sinuses; The upper lip and palate; The jaws and skull bones; The inner, middle and outer ear.

New in Version 1.3:-

‘Schematic for weeks 5 to 38’
Complements the ‘Timetable for weeks 1 to 4’ and gives access to three new fully-illustrated topics, each providing crucial background to the development of more than one organ system.

  • The organization of somitic derivatives Origin and subdivision of somites; Derivatives of dermomyotome and sclerotome; Segmentation of spinal nerves; Intersegmental basis of vertebrae; Ossification of vertebrae and ribs; Anomalies.
  • The body cavities and diaphragm Formation and folding of the coelom; The pericardio-peritoneal canals, pericardial cavity and pleural cavities; Final subdivision of the coelom; Completion and innervation of the diaphragm; Anomalies.
  • The organization of the primitive pharynx The pharynx in the early embryo; Components of the primitive pharynx; The stomodaeum and Rathke’s pouch; The tongue; The thyroid gland; The respiratory tract; The pharyngeal pouches; The pharyngeal arch arteries; The pharyngeal cartilages; The pharyngeal clefts; Anomalies.

‘Conception and Contraception’
Extends ‘The Germ Line’ to include an overview of key steps in fertility, showing how these are relevant to the understanding of clinical infertility and to contraceptive strategy, now and in future.

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