ANATOMY
GENITO URINARY AND ADRENAL
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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: -A small group of cells in the early mammalian embryo is induced to become primordial germ cells by signals produced by neighboring cells.
Detailed explanation-2: -In the 4thweek, PGCs have migrated and are present in the yolk sac near the base of the allantois.
Detailed explanation-3: -EMBRYOLOGY OF OVARIAN DEVELOPMENT: NATURE OF GENES TO BE POSTULATED. Primordial germ cells originate in the endoderm of the yolk sac and migrate to the genital ridge to form the indifferent gonad.
Detailed explanation-4: -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-5: -After specification Primordial germ cells (PGCs) are carried into the embryo by the midgut primordium. PGCs polarize and migrate through the midgut epithelium at stages 9–10 (∼4.5h After Egg Laying (AEL)).