Consider the following statements : 1. Genetic changes can be introduced in the cells that produce eggs or sperms of a prospective parent. 2. A person's genome can be edited before birth at the early embryonic stage. 3. Human induced pluripotent stem cells can be injected into the embryo of a pig. Which of the statements given above is/are correct ?

Identifies where human germ cells (sperms) are produced (testes) and that spermatogenesis is a defined physiological process.

A student could use this to ask whether interventions (e.g., gene editing) targeted to the testes could alter sperm DNA prior to fertilisation.

Describes female germ cells (eggs) residing in ovaries and the site of fertilisation (fallopian tube) in humans.

One could extend this by considering whether gene-altering interventions to ovarian eggs or pre-fertilisation gametes might change the genetic material passed on.

Explains that gametes carry only half the parent's genetic material and combine at fertilisation to form a complete set.

A student can infer that changing the DNA in gametes would alter the genetic input to the zygote and thus be inherited.

States germ cells take one chromosome from each pair so that progeny restore the normal chromosome number—highlighting the mechanism by which parental DNA is transmitted.

This suggests that modifying chromosomes in germ cells could be propagated into the offspring's genome; a student could combine this with knowledge of editing tools to evaluate feasibility.

Defines genetic modification as altering hereditary material (DNA) in a way not occurring by normal mating or recombination.

A student could use this definition to frame germline editing as a form of genetic modification and then compare plant/animal examples to infer analogous possibilities in human germ cells.

Explains that a basic event in reproduction is creation and copying of DNA—cells build copies of DNA during reproduction.

A student could combine this with the basic fact that editing DNA at the single-cell or very early multi-cell stage might be propagated into later copies, so check whether interventions at DNA-copying stages can change the embryo's future cells.

Describes sexual reproduction involving special cell lineages and the problem of halving chromosomes, highlighting that early reproductive cells and stages have distinct DNA states.

Using external knowledge that the zygote/early embryo is the stage before cell lineages diverge, a student could infer that editing at that stage could affect germline vs somatic lineages and thus heritability.

Shows that a zygote develops into an embryo either inside the mother's body (mammals) or in an egg (birds), indicating where and when early development occurs.

A student could use a world/biological map of developmental environments to think about practical access to embryos for intervention (e.g., in vitro embryonic manipulation vs in utero), and then investigate whether human embryos are experimentally reachable at early stages.

Notes that the embryo implants in the uterine lining and then develops with maternal support, marking a timeline of developmental stages after fertilisation.

A student could combine this with basic timing facts (when implantation occurs) to ask whether there is a window before/after implantation when editing might be feasible and what barriers (access, maternal environment) exist.

States that humans give birth after internal development and that young gradually grow and develop over time, emphasising stages from embryo to birth.

A student could extend this by mapping embryonic stages to the possible timing of interventions, prompting a search for whether interventions at the 'early embryonic' stage would affect development up to birth.