WebFertilization, pictured in Figure 24.23 a is the process in which gametes (an egg and sperm) fuse to form a zygote. The egg and sperm each contain one set of chromosomes. To ensure that the offspring has only one complete diploid set of chromosomes, only one sperm must fuse with one egg. In mammals, the egg is protected by a layer of ... WebSep 4, 2024 · Embryonic Development Gastrulation. Late in the second week after fertilization, gastrulation occurs when a blastula, made up of one layer,...
What is the Embryonic Stage of Prenatal Development?
WebOct 30, 2024 · Two separate stages of prenatal development happen during the embryonic development period. Those two stages are the germinal stage and the … WebMar 11, 2024 · Stages of Prenatal Development Germinal Stage of Prenatal Development. The germinal stage begins at conception when the sperm and egg cell … blackwall railway station
24.6. Fertilization and Early Embryonic Development
WebIt comprises of a hollow nerve cord. The key difference between protostomes and deuterostomes is the fate of the blastopore during their embryonic development. The blastopore in a protostome develops into a mouth, whereas the blastopore in deuterostomes develops into an anal opening. WebJun 8, 2024 · Gastrulation. The typical blastula is a ball of cells. The next stage in embryonic development is the formation of the body plan. The cells in the blastula rearrange themselves spatially to form three layers of cells in a process known as gastrulation. During gastrulation, the blastula folds upon itself to form the three layers of … WebEmbryonic Membranes. During the second week of development, with the embryo implanted in the uterus, cells within the blastocyst start to organize into layers. Some grow to form the extra-embryonic membranes needed to support and protect the growing embryo: the amnion, the yolk sac, the allantois, and the chorion. fox ncaa brackets 2023