Question

Cells of rauber are

• A. Trophoblast cells in contact with the uterine wall
• B. Secretory cells of the endometrium
• C. Trophoblast cells in contact with inner cell mass of the blastocyst
• D. Inner cell mass of blastocoel

Answer 1

The correct option is C

Trophoblast cells in contact with inner cell mass of the blastocyst

The correct option is option C.

Explanation of correct option:-

1. Cells of rauber are trophoblast cells in contact with the inner cell mass of the blastocyst.
2. Cells of rauber are a thin layer of trophoblast that overlies the inner cell mass of blastocyst in the early mammalian embryo.
3. The trophoblast layer of the blastocyst is not involved in embryo formation.
4. It forms the external parts of embryos like extra embryonic membranes such as chorion and amnion which provide protection and nourishment to the embryo.

Explanation of incorrect options:-

Option A

1. A layer of cells that helps a developing embryo attack the wall of the uterus is called the trophoblast.
2. It protects the embryo and forms a part of the placenta. The placenta acts as a connection or link between the mother and the developing embryo.

Option B

1. After ovulation occurs, the endometrium enters the luteal or secretory phase.
2. Where the corpus luteum secretes progesterone which prepares the endometrium for the implantation of an embryo if fertilization does not occur then menstrual flow begins.

Option D

1. The blastocyst is made up of the outer cell layer called the trophoblast and the inner cell mass.
2. The inner cell mass helps in the formation of all the tissues of the embryo and differentiates into the embryo proper.
3. Whereas, the trophoblast will form the placental structures.

Final answer: - Cells of rauber are trophoblast cells in contact with the inner cell mass of the blastocyst.