Which of the following cells have the potency to give rise to all the tissues and organs?
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → Inner cell mass (stem cells)
The embryo first forms a hollow ball called the blastocyst. Its cells are arranged in two parts: an outer layer, the trophoblast, and an inner group, the inner cell mass. The trophoblast attaches to the wall of the uterus, while the inner cell mass becomes the embryo.
Option (1) Trophoblast — Incorrect. The trophoblast is the outer layer of the blastocyst. It attaches to the endometrium and helps form the link with the mother. It does not become the tissues of the embryo.
Option (2) Inner cell mass (stem cells) — Correct. The inner cell mass contains stem cells, which can form all the tissues and organs. It gives rise to the three germ layers (ectoderm, mesoderm and endoderm).
Option (3) Placenta — Incorrect. The placenta is an organ, not a group of cells that forms the body. It links the embryo with the mother, supplies food and oxygen, removes wastes and makes hormones.
NCERT Extract:
Fertilisation and Implantation – “… The blastomeres in the blastocyst are arranged into an outer layer called trophoblast and an inner group of cells attached to trophoblast called the inner cell mass. The trophoblast layer then gets attached to the endometrium and the inner cell mass gets differentiated as the embryo.”
Pregnancy and Embryonic Development – “… It needs to be mentioned here that the inner cell mass contains certain cells called stem cells which have the potency to give rise to all the tissues and organs.”