A sperm has just fertilised a human egg in the Fallopian tube. Trace the events that the fertilised egg will undergo upto the implantation of the blastocyst in the uterus.

Generally, what is the site of fertilisation in human being? (Vagina, Uterus, Fallopian tube and Ovary)

(i) Explain the events taking place at the time of fertilisation of an ovum in a human female. (ii) Trace the development of the zygote up to its implantation in the uterus. (iii) Give the name and draw a labelled sectional view of the embryonic stage that gets implanted.

With a labelled diagram show the transport of ovum , fertilisation and passage of growing embryo through Fallopian tube till it gets implanted in the uterus.

Consider the following statements. (i) Polyspermy may bring about fertilisation of egg by more than one male nucleus or the supernumerary sperms may fertilise other components of embryo sac much as synergids or antipodals. (ii) In angiosperms, pollen tube is normally an unbranched structure which ususally persists after fertilisation. (iii) Intine is the inner, pectocellulosic layer of pollen grain wall which is destroyed during acetolysis. (iv) Exine layer of pollen grain comprises of an outer non-sculptured layer sexine and an inner sculptured layer tectum. Which of the following combinations of above given statements is correct ?

Which two of the following statements are incorrect regarding in vitro fertilisation ? (i) In this method, ova from the wife/donor female and sperms from the husband/donor male are induced to form zygote in the uterus (ii) If the embryo is having 2 blastomeres, it is transferred into the uterus (iii) If the embryo is with more than 8 blastomeres, it is transferred into the uterus. (iv) The baby thus produced is called test tube baby.

In oogensis, egg is fertilised by sperm at which stage?

Assertion : IVF is fertilisation outside the body of woman Reason : The zygote upto 8 blastomeres could be transferred into the Fallopian tube

How is the child affected, if it has grown from the zygote formed by an XX-egg fertilised by a Y-carrying sperm? What do you call this abnormality?

Due to nondisjunction of chromosomes during spermatogensis, some sperms carry both sex chromosomes (22A + XY) and some sperms do not carry any sex chromosome (22A + O). If these sperms fertilise normal eggs (22A + X), what types of genetic disorders respectively appear among the offspring ?

Due to the nondisjunctiuon of chromosomes during spermatogenesis, sperms carry both sex chromosomes (22A + XY) and some sperms do not carry any sex chromosome (22A + O). If these sperms fertilise normal eggs (22A + X), what types of genetic disorders appear among the offsprings ?