The oogonium becomes... | enclosed within the secondary oocyte where it then becomes ovulated by sperm |
What occurs to the secondary oocyte after it undergoes ovulation? | the oocyte undergoes meiosis II and thus produces and ovum |
What begins implantation? | The blastocyst begins implantation |
When does implantation begin? | Implantation begins about 6 days after conception |
What structure grows into the blastocyst? | the maternal blood vessels grow into the blastocyst structure |
What does a blastocyst contain? | - an inner cell mass
- outer trophoblast |
What are the 2 layers the trophoblast forms into? | 1. cytrophoblast (inner layer)
2. Syncytiotrophoblast (outer layer) |
Name the structure | Trophoblast |
Name the structure | Blastocyst cavity |
Name the structure | Inner cell mass |
Name the structure | Uterine endometrial epithelium |
Name the structure | Endometrium |
Name the structure | Lumen of Uterus |
Name the structure | Syncytiotrophoblast |
Name the structure | Cytotrophoblast |
What is ocurring in this photo? | the blastocyst begins to implant into the uterus lining the endometrium |
How does the placenta form? | the blastocyst gives rise to finger like outgrowths called chorionic villi that interdigitate into depressions called crypts in the wall of uterus |
Name the structure | Uterus |
Name the structures | Amnion and amnionic cavity |
How is the fetus recieving its nutrion durng week 4 | though the umbilical vessels that connect it to the placenta |
Name the structure | Decidua capsularis |
Name the structure | Maternal blood |
What are the 2 parts of the placenta? | the fetal placenta and the maternal placenta |
What is the function of the placenta? | The placenta engages in exchange across the chorionic villi between maternal and fetal blood
- provides fetus with nutrients and oxygen
- Disposes of waste
- allows hormonal signals to be sent to the mother |
When is the placenta fully formed? | By week 13 the placenta is fully formed |
What does the placental barrier consist of? | The placental barrier consist of all three layers of the chorionic villi |
What diffuses across the placenta from the mother to the fetus? | sugars, fats, and oxygen diffuse from the mother to fetus |
What diffuses across the placenta from the fetus to the mother | Urea and carbon dioxide diffuse from the fetus to the mother |
What else is transported across the placenta? | Maternal antibodies, viruses, alcohol, and heroin cross the placental barrier |
Name the structure | Decidua Basalis |
Name the structure | Chorionic villi |
Name the structure | Decidua Capsularis |
Name the structure | Basal layer of endometrium |
Name the structure | Decidus Basalis which is the maternal portion of the placenta |
Name the structure | Chorion which is the fetal portion of the placenta |
Name the structure | Chorionic villus which contains fetal capillaries |
Name the structure | Umbilical cord which contains the umbilical arteries and veins as well |
Name the structure and what the structure contains? | Zygote; the zygote contains chromosomes from male and female gametes |