Alaqah
• Alaqah is a Blood clot or Leech like structure. • It is something suspended or attached to a
surface.
• This term is so important to remember that there is a complete surah in Qur’an called Surah Al-Alaq.
• Here are first five ayyat of Surah Al-Alaq.
• This is the first revelation sent to Muhammad (SAS) in the cave of Hira.
• The importance of Alaqah is very much increased when we see that in the very first revelation the terminology of “alaq” is used.
• Read (O Prophet), in the name of your RABB (Lord), Who ceated
• HE created insan from alaq (a clot of congealed blood).
• Read: and your RABB is Most Generous.• Who taught knowledge by “qalam” (pen).• HE taught insan what he did not know.• • Al-Alaq. Surah 96, Ayat 1-5, Para 30
Alaqah
• This Qur’anic term refers to the presomite embryo.
• It starts when the implantation begins and ends when formation of somites begins.
• It extends for about 14 days. • It starts on day 7 with the embedding of
blastocyst and is completed on day 20 when first pair of somites appears.
• According to modern scientific knowledge we can discuss Alaqah in two stages:
• Alaqah-1. This is bilaminar germ disc.• Alaqah-2. This is trilaminar germ disc.
• BILAMINAR GERM DISC• Second week of intra-uterine life• IMPLANTATION• Implantation of the blastocyst begins at the
end of the first week and ends by the end of second week.
• Morula enters uterine cavity on about 4th day.
• At about 6th day after fertilization the embryonic pole of the blastocyst becomes attached to the endometrium and start penetrating into it.
Implantation Site
• The blastocyst usually implants in the midpoint of the body of the uterus, more frequently on the posterior than on the anterior wall.
• Although anterior wall is also considered the normal site of implantation but the implantation on posterior wall of uterus is said to be the classical normal site of implantation.
• Implantation almost always occurs between the openings of the glands and it is always close to a maternal capillary suggesting some type of tropism toward maternal blood.
Proliferation of trophoblast
• The trophoblasts now start proliferating rapidly and soon differentiate into two layers:
• An inner cytotrophoblast (cellular trophoblast) consisting of mono-nucleated cells.
• An outer syncytial trophoblast (syntrophoblast or syncytiotrophoblast) consisting of a multinucleated protoplasmic mass without individual cell boundaries.
• Day 8
• So on eighth day three events occur:• Trophoblast forms two layers, cytotrophoblast
and syncytial trophoblast.• Embryoblast gives rise to two layers epiblast
and hypoblast.• Amniotic cavity develops
• Day 9