Fertilization through gastrulation, the three germ layers, and their tissue derivatives, one fact per card.
34 cards · basic cards · AI-written, checked twice. Edit anything.
- Fertilization normally occurs in the ____ of the uterine (fallopian) tube.
- ampulla
- What reaction alters the zona pellucida immediately after fertilization to block additional sperm from entering the oocyte?
- The cortical (zona) reaction.
- What is the chromosome number of a normal human zygote?
- 46, diploid (2N).
- What term describes the rapid mitotic divisions of the zygote that occur without an overall increase in size?
- Cleavage.
- What solid ball of blastomeres results from cleavage?
- The morula.
- Around what day after fertilization does the morula enter the uterine cavity?
- Day 3 to 4.
- What is the fluid-filled cavity that forms inside the morula, converting it into a blastocyst?
- The blastocele (blastocyst cavity).
- Which outer cell layer of the blastocyst gives rise to the placenta?
- The trophoblast.
- Which cluster of cells inside the blastocyst gives rise to the embryo proper?
- The inner cell mass (embryoblast).
- Around what day after fertilization does implantation of the blastocyst into the endometrium occur?
- Day 6.
- Into which two layers does the trophoblast differentiate?
- Cytotrophoblast and syncytiotrophoblast.
- Which trophoblast layer is mitotically active and retains distinct cell boundaries?
- The cytotrophoblast.
- Which trophoblast layer is invasive, lacks distinct cell boundaries, and secretes hCG?
- The syncytiotrophoblast.
- hCG secreted by the syncytiotrophoblast maintains which ovarian structure during early pregnancy?
- The corpus luteum.
- During week 2, the inner cell mass reorganizes into a bilaminar germ disc made of which two layers?
- Epiblast and hypoblast.