In what ways is fertilisation in a plant:
(a) similar to fertilisation in a human?
(b) different from fertilisation in a human?

(a) In both human and plants, fertilisation include the fusion of male gametes and female gametes in the haploid (n) state to form a diploid (2n) zygote. 

(b) In human, fertilisation involves the fusion of male gamete, sperm, with the female gamete, egg, to form a diploid zygote.

While in plants, fertilisation involves the fusion of male gamete, pollen, with the female gamete, egg, to form a diploid zygote.