In over 60 per cent of angiosperms, pollen grains are shed at the 2-celled stage (vegetative cell and generative cell) . In these cases, the generative cell divides to form two male gametes during the growth of the pollen tube in the stigma, meaning double fertilisation still occurs . The other statements are correct: the vegetative cell is indeed larger than the generative cell , pollen can remain viable for months in families like Rosaceae and Solanaceae , and the intine layer consists of cellulose and pectin .