Embryology 6: Placenta & Membranes MCQ

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the significance of the invasion of cytotrophoblast cells into spiral arteries?

It leads to high pressure blood flow from the maternal side.

It allows for low pressure and high volume blood flow. (correct)

It decreases the amount of maternal blood available to the placenta.

It prevents maternal blood from entering the intervillous spaces.

What condition may develop as a direct result of inadequate transformation of maternal vessels by cytotrophoblast cells?

Thromboembolic disease

Preeclampsia (correct)

Gestational diabetes

Eclampsia

Which statement describes the placental barrier before the 5th month of pregnancy?

It does not provide any barrier between maternal and fetal blood.

It consists only of syncytiotrophoblast cells.

It is made up of maternal blood vessels only.

It includes endothelium, cytotrophoblast, and syncytiotrophoblast. (correct)

What happens to the placental barrier after the 5th month of pregnancy?

It becomes thinner with fewer cell layers. Signup and view all the answers

What is a hallmark of gestational trophoblastic neoplasia?

Excessive proliferation and invasion by cytotrophoblast cells. Signup and view all the answers

What is the primary role of human chorionic somatotropin produced by the placenta?

To regulate maternal metabolism of glucose Signup and view all the answers

Which of the following is NOT a component of the TORCH complex that can cross the placenta?

Ebola virus Signup and view all the answers

What hormone does the placenta predominantly produce by the second trimester?

Estrogens and progesterone Signup and view all the answers

How does the placenta prevent maternal rejection of the embryo?

By lacking MHC in syncytiotrophoblast and villus cytotrophoblast Signup and view all the answers

What plays a significant role in hormone production by the placenta during the 3rd trimester?

Fetal adrenal glands Signup and view all the answers

What is the function of the decidua basalis during pregnancy?

It serves as the interface between the implanted embryo and the myometrium. Signup and view all the answers

At what point does the decidua capsularis begin to degenerate during pregnancy?

At the third month of pregnancy. Signup and view all the answers

Which statement accurately describes the chorion frondosum?

It develops on the side of the decidua basalis. Signup and view all the answers

What happens to the amnion and chorion during pregnancy?

They fuse together to form the amniochorionic membrane which eventually fuses with the decidua parietalis. Signup and view all the answers

Which of the following correctly describes the decidua parietalis?

It has no direct relation to the embryo. Signup and view all the answers

What is the primary role of the placenta in the relationship between the embryo and mother?

Facilitates the exchange of oxygen, nutrients, and waste Signup and view all the answers

Which statement correctly describes the origin of the amnion?

It develops from the inner cell mass. Signup and view all the answers

What is one of the major functions of the amniotic sac?

Buffers against mechanical injury in a liquid environment Signup and view all the answers

How does the composition of amniotic fluid change by the 11th week of gestation?

It transitions to being predominantly made up of fetal urine. Signup and view all the answers

What property of the amniotic membrane contributes to its use in wound healing?

High concentrations of cytokines and essential growth factors Signup and view all the answers

Which of the following statements accurately describes a characteristic of amniotic fluid?

It increases in volume as the embryo grows. Signup and view all the answers

Why is the amniotic membrane considered non-immunogenic?

It contains no cellular machinery to provoke an immune response. Signup and view all the answers

What is the main purpose of the chorion in relation to the embryo?

To mediate communication and nutrient exchange with the mother Signup and view all the answers

What condition is often associated with defects of the caudal part of the neural tube?

Polyhydramnios Signup and view all the answers

What complication can occur due to polyhydramnios related to the uterine wall?

Premature rupture of membranes Signup and view all the answers

What can happen if an amniotic band constricts a part of the fetus's body?

Necrosis of the constricted area Signup and view all the answers

Which nutrient is not absorbed through histiotrophic nutrition from the yolk sac?

Vitamin C Signup and view all the answers

What is the consequence of the yolk sac ceasing to function as a source of nutrition?

Start of placental function Signup and view all the answers

What potential risk is associated with fetal malposition due to polyhydramnios?

Umbilical cord prolapse Signup and view all the answers

Which of the following is NOT a complication of polyhydramnios?

Fetal weight loss Signup and view all the answers

What structure is incorporated into the body of the embryo during its folding?

Yolk sac Signup and view all the answers

What condition is characterized by umbilical blood vessels running over or in close proximity to the cervical os?

Vasa previa Signup and view all the answers

Which type of hydatiform mole has a 2% risk of evolving into choriocarcinoma?

Complete mole Signup and view all the answers

What is a potential serious consequence of a placental abruption during the third trimester?

Maternal shock and fetal distress Signup and view all the answers

What distinguishes dizygotic twins from monozygotic twins?

Dizygotic twins develop from two separate oocytes Signup and view all the answers

What can excessive production of hCG from a hydatiform mole cause?

Hyperthyroidism and hyperemesis Signup and view all the answers

Which condition involves carcinoma of the trophoblast potentially spreading to other organs?

Choriocarcinoma Signup and view all the answers

What complication can arise from twinning due to blood vessel anastomosis between embryos?

Congestive heart failure Signup and view all the answers

In a partial mole, what is commonly present that differentiates it from a complete mole?

Presence of fetal tissue Signup and view all the answers

Study Notes

Extraembryonic Membranes

The embryo establishes a parasitic relationship with the mother for oxygen, nutrients, and waste elimination.
The embryo must avoid rejection as a foreign body.
The placenta and extraembryonic membranes facilitate communication with the mother.
The placenta arises from the trophoblast.
The amnion, yolk sac, allantois, and extraembryonic mesoderm derive from the inner cell mass.

Amniotic Membrane and Cavity

The amniotic membrane encloses the embryo completely.
Functions of the amniotic sac:
- Cushioning against mechanical injury.
- Accommodating growth.
- Allowing fetal movement.
- Protecting the fetus from adherence to the chorionic wall.
- Acting as a barrier to infections.
- Maintaining a consistent temperature.
- Maintaining homeostasis of fluids and electrolytes.
Amniotic membranes can be used in treating wounds and burns.
They show anti-inflammatory and anti-angiogenic properties.
Used in ophthalmic surgery (cornea restoration).
Stem cells within amniotic membranes are a research focus.

Amniotic Membrane Functions

Contains significant cytokines and growth factors.
Reduces pain when applied to wounds.
Increases wound healing.
Has antibacterial properties.
Is not immunogenic (no foreign material identification).
Acts as a biological barrier.
Supports cell migration and proliferation.
Reduces inflammation.
Reduces scar tissue formation.

Amniotic Fluid Composition

Amniotic fluid composition changes significantly (and is different to adult urine).
Primarily urine of the embryo, starting in the 11th week.
Fetal urine lacks waste products, as these are excreted through the placenta.
Lung secretions are also released into the amniotic fluid.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Explore the crucial roles of extraembryonic membranes, including the placenta and amniotic sac, in supporting embryonic development. This quiz covers the relationship between the embryo and mother, as well as the functions of the amniotic membrane in protecting and nurturing the fetus. Test your knowledge on these essential biological structures.