Asexual reproduction in flower

Asexual reproduction in flower
1. Is it true that all flowering plants carry out sexual reproduction? How about roses? I've heard that some rose species carry out asexual reproduction...

ans: not all of the flowering plant use sexual reproduction but normally rose
use sexual reproduction, but in some case , people would like to retain good
characteristic so they would use some artifical ways to produce a offspring for
that flower . this also belongs to asexual reproduction.

2. If there areflowering plants that carry out asexual reproduction, then what do those flowers look like? Do they have the features similar to flowers that carry out sexual reproduction (e.g. sepals, petals, stamens, carpels...)?

ans: for the plant use asexual reproduction, there are four type: corm e.g.
Gladiolous(劍蘭), water chestnut; bulb e.g. onion; rhizome e.g. ginger(with
flower), iris, lotus(with flower); stem tuber e.g potato.

Do the flowering plants that carry out asexual reproduction have pollen grains and ova? If so, then what are they used for?

no, in sexual reproduct, pollen grains is used for carry male gamete; in asexual reproduct
there nis no fusion of gamete so pollen grain would not involve.

And is it possible that those flowers carry out both sexual and asexual reproduction at the same time?

it is only possible when asexual reproduction refer to artifical ways e.g. cutting,
tissue culture