Multiple choice

Blastocoele is the primordial, fluid-filled cavity inside the early forms of embryo. It leads to the formation of which of the following?

  1. Gestational sac

  2. Primary yolk sac

  3. Chorionic cavity

  4. Septum primum

  5. Intraembryonic coelom

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Around the 9th day, cells from the hypoblast spread around the blastocoele, forming the exocoelomic or Heuser's membrane. When the blastocoele is surrounded by this membrane, it is referred to as the primary yolk sac or exocoelomic cavity.