Fetal /choroidal fissure is closed by which week of gestation
**Core Concept**
The fetal choroidal fissure is a critical anatomical structure during embryonic development, which eventually closes to form part of the anterior segment of the eye. The closure of this fissure is essential for the normal formation of the eye.
**Why the Correct Answer is Right**
The fetal choroidal fissure closes by the 10th week of gestation, marking a significant milestone in eye development. This process is facilitated by the growth and invagination of the optic cup, which eventually separates the anterior and posterior segments of the eye. The closure of the choroidal fissure is crucial for the formation of the anterior chamber, iris, and lens.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because the closure of the choroidal fissure occurs earlier than the 8th week of gestation. The development of the eye is a complex process, and the closure of the choroidal fissure is an essential step in this process.
**Option B:** This option is incorrect because the closure of the choroidal fissure does not occur until after the 12th week of gestation. The development of the eye is a gradual process, and the closure of the choroidal fissure is a critical milestone that occurs later in gestation.
**Option C:** This option is incorrect because the closure of the choroidal fissure is not directly related to the formation of the vitreous humor. While both processes occur during embryonic development, they are distinct and separate events.
**Clinical Pearl / High-Yield Fact**
A key point to remember is that the closure of the choroidal fissure marks the beginning of the anterior segment of the eye, which eventually gives rise to the iris, lens, and anterior chamber.
**Correct Answer:** C. 12th week.