Identify the correct statement for Zygote Intra-Fallopian Transfer (ZIFT).
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → The in-vitro technique involving the transfer of an early embryo into the fallopian tube of the same female from whom the egg was taken.
Option (1) The in-vitro technique involving the transfer of an early embryo into the fallopian tube of the same female from whom the egg was taken. — Correct. In ZIFT the ovum and sperm are made to fuse in the laboratory (in vitro). The zygote or early embryo, with up to 8 blastomeres, is then placed in the fallopian tube. Here the egg is the wife’s own.
Option (2) The in-vitro technique involving the transfer of an ovum collected from a donor into the fallopian tube of another female. — Incorrect. An ovum, not an embryo, is transferred here, so this is GIFT (gamete intra fallopian transfer). And in GIFT fertilisation takes place inside the body, so it is not an in-vitro technique.
Option (3) The in-vivo technique involving the transfer of an early embryo into the fallopian tube of the same female from whom the egg was taken. — Incorrect. The place of transfer is right, but the zygote of ZIFT is formed outside the body. In vivo means inside the body, so the word is wrong.
Option (4) The in-vivo technique involving the transfer of an ovum collected from a donor into the fallopian tube of another female. — Incorrect. This describes GIFT. It helps a female who cannot produce ova but can provide the right place for fertilisation. No zygote is transferred.
NCERT Extract:
Infertility – “… In vitro fertilisation (IVF–fertilisation outside the body in almost similar conditions as that in the body) followed by embryo transfer (ET) is one of such methods. In this method, popularly known as test tube baby programme, ova from the wife/donor (female) and sperms from the husband/donor (male) are collected and are induced to form zygote under simulated conditions in the laboratory. The zygote or early embryos (with upto 8 blastomeres) could then be transferred into the fallopian tube (ZIFT–zygote intra fallopian transfer) and embryos with more than 8 blastomeres, into the uterus (IUT – intra uterine transfer), to complete its further development.”