This stage of embryonic development requires laminin-111 for the assembly of Reichart’s membrane and is characterized by pinopode formation. For 10 points each:
[10h] Name this stage whose namesake “window” usually occurs between day 19 and 21 of the menstrual cycle. After this stage occurs, fused syncytiotrophoblasts (“syn-cytio-tropho-blasts”) invade the decidua basalis, which ultimately forms chorionic villi (“kor-ee-ON-ic VILL-eye”).
ANSWER: implantation [accept word forms of blastocyst implanted in the endometrium; accept nidation or embedding or apposition or zona hatching; prompt on adhesion]
[10m] The innermost cytotrophoblasts secrete a hyperglycosylated form of this hormone that further promotes implantation. This hormone maintains the corpus luteum and is detected in a pregnancy dipstick test.
ANSWER: human chorionic gonadotropin [or hCG; accept beta-hCG; accept hyperphosphorylated human chorionic gonadotropin or hCG-H; reject partial answers]
[10e] Most ectopic pregnancies occur after improper implantation of the blastocyst in this paired structure. Fertilization normally occurs in this structure’s ampulla, which connects the infundibulum to the isthmus.
ANSWER: Fallopian tubes [accept uterine tubes; or ovarian tubes; accept oviducts]
<Warwick A, Biology>