HISTOLOGY
URINARY SYSTEM
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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Germinal cells
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Primordial germ cells
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Primary oocytes
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Leydig cells
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Detailed explanation-1: -When the egg is fertilized and divides repeatedly to produce the cells of the early embryo, the cells that inherit specific molecules localized in a particular region of the egg cytoplasm become primordial germ cells.
Detailed explanation-2: -Primordial germ cells originate in the endoderm of the yolk sac and migrate to the genital ridge to form the indifferent gonad.
Detailed explanation-3: -During Drosophila embryogenesis, the primordial germ cells move from the posterior pole to the gonads (Figure 19.12). The first step in this migration is a passive one, wherein the 30–40 pole cells are displaced into the posterior midgut by the movements of gastrulation.
Detailed explanation-4: -Primordial germ cells (PGCs) derive from the epiblast, the outer ectodermal layer of the embryo. Primordial germ cells (PGCs) subsequently move to the yolk sac wall and then migrate along the dorsal mesentery of the hind gut to the gonadal ridge.