In a pollen grain, larger nucleus is

After demonstration of totipotency, a botanist wishes to produce identical plants from an angiosperm by tissue culture. The parts or tissues which are likely to yield haploid embryos are

The thin and continuous wall layer of pollen is

Examine the figure given below and select the right option giving all the four parts $a, b, c$ and $d.$ Correctly identify

$a\quad \;b\quad\;c\quad\;d$

During meiosis in pollen mother cell the daughter cells are interconnected by passages. The whole structure is called