Ido not understand and i'm struggling with these biology questions me will give 10 points) how are a seed coat a pollen grain and a spore wall adaptive structures?

seed coat protects the cotyledons and embryo from outer environment and from attack of pathogens

pollen grain has a sculptors covering with weak points(germ pores) in it through which pollen tube comes out.

A spore is generally protected by 2-3 tough resistant walls around to tied over the unfavourable conditions.

"do a testcross with a homozygous recessive plant."

the answer is b.) hydrogen bonds between bases.