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E L IFE An Educational Material Izel Praise Fernandez EMBRYOL A52
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Also commonly known as conception-is the fusion of male and female gametes
Fertilization
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Fertilization to Organogenesis
Blastulation
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Gastrulation
Process by which the morula becomes a blastula, which gives rise to the very earliest stages of the embryo
The blastula reorganizes itself into a gastrula by folding itself inward
Life begins with a single point where development takes place in each stage.
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Neurulation
Organogenesis
Folding process in vertebrate embryos, which includes the transformation of the neural plate into the neural tube
Process by which the three germ tissue layers of the embryo, which are the ectoderm, endoderm, and mesoderm
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Fertilization Through fertilization, the egg and sperm are saved: the egg is activated to begin its developmental program, and the haploid nuclei of the two gametes come together to form the genome of a new diploid organism.
Once a capacitated sperm has penetrated the layer of follicle cells, it binds to the zona pellucida. The zona usually acts as a barrier to fertilization across species, and removing it often eliminates this barrier.
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Blastulation The formation of a segmentation cavity or blastocoele within a mass of cleaving blastomeres and rearrangement of blastomeres around this cavity in such a way as to form the type of definitive blastula characteristic of each species.
Morula
The blastocoele originates as an intercellular space which sometimes arises as early as the four- or eight-cell stage. The blastula is usually a hollow sphere.
Blastula
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Blastulation Trophoblast
Embryoblast
The deposition of embryoblast or inner mass cells is due to the water intake of the embryo. The embryoblast will become the organs.
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Blastulation Amniotic cavity Epiblast
Trophoblast
Hypoblast
Blastocoel Primary yolk sac
Epiblast
Epiblast
Hypoblast Blastocoel
Hypoblast Blastocoel
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Gastrulation Gastrulation is defined as an early developmental process in which an embryo transforms from a one-dimensional layer of epithelial cells (blastula) and reorganizes into a multilayered and multidimensional structure called the gastrula.
The process of gastrulation generates the three primary germ layers (ectoderm, endoderm, mesoderm), which primes the system for organogenesis and is one of the most critical steps of development.
Blastopore
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Gastrulation
Migrating cells
Blastula
Cell migrations in early gastrula
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Gastrulation
Blastomeres Ectoderm Endoderm Blastocoel Blastopore
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Neurulation Neurulation is the embryological process which forms the precursors of the central nervous system and occurs after gastrulation has established the three primary cell layers of the embryo: ectoderm, mesoderm, and endoderm.
Neurulation in vertebrates results in the formation of the neural tube, which gives rise to both the spinal cord and the brain. Neural crest cells migrate away from the neural tube and give rise to a variety of cell types, including pigment cells and neurons.
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Neurulation Neural tube
Mesoderm
Notochord
Ectoderm Neural plate
Endoderm Neural tube
Mesoderm
Somite
Notochord Spinal ganglion
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Neurulation Notochord forms from mesoderm cells soon after gastrulation is complete. It orchestrates on which organ does the layers become into.
Signal from notochord cause inward folding of ectoderm and neural plate.
Ends of neural plate fuse and disconnect to form an autonomous neural plate.
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Organogenesis Organogenesis is the period of animal development during which the embryo is becoming a fully functional organism capable of independent survival.
Organogenesis is the process by which specific organs and structures are formed, and involves both cell movements and cell differentiation. Organogenesis requires interactions between different tissues. These are often reciprocal interactions between epithelial sheets and mesenchymal cells.
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Organogenesis
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Organogenesis Endoderm
Yolk sac Primitive gut Lung Liver Pancreas Digestive tubes
Mesoderm
Notochord Somite Intermediate mesoderm Lateral plate mesoderm Nucleus pulposus Sclerotome, Dermatome, Myotome Kidney and gonads Somatic and splanchnic mesoderm
Ectoderm
Integumentary system Brain Spinal cord Neural crest
Also commonly known as conception-is the fusion of male and female gametes
Fertilization
Blastulation
Gastrulation
Neurulation
Organogenesis
Process by which the morula becomes a blastula, which gives rise to the very earliest stages of the embryo
The blastula reorganizes itself into a gastrula by folding itself inward
References Alberts B, Johnson A, Lewis J, et al. (2002). Molecular Biology of the Cell (4th edition). Garland Science. https://www.ncbi.nlm.nih.gov/books/NBK26843/ Muhr J, Ackerman KM. (2022). Embryology, Gastrulation. In: StatPearls [Internet]. StatPearls Publishing. https://www.ncbi.nlm.nih.gov/books/NBK554394/
Folding process in vertebrate embryos, which includes the transformation of the neural plate into the neural tube
Process by which the three germ tissue layers of the embryo, which are the ectoderm, endoderm, and mesoderm
Izel Praise Fernandez EMBRYOL A52