How does pollination occur in flowering plants

Bees have a pouch on their legs in which it collects pollen, so when the bee lands on a flower... the pollen dust pollinates the flower

Pollination is the transfer of pollen grains from the anther of a flower to the stigma. There are two types of pollination namely self pollination and cross pollination. With the self pollination, the pollination takes place on the same plants probably by wind but with the cross pollination agents such as wind and insects(butterflies,bees) transfers the pollen grains from the anther of a flower to stigma of a different flower. Insects may be attracted by a flower based on how colourful, nice looking, attractive and nice-sented the flower may be.   

No because the eaeht is on a 23.5 degree axis tilt and so when it is winter the northern hemisphere is pointing away from the sun and the soutubern hemisphere is pointing toward the sun

Gravitational force i believe