They mostly don´t intend to do so, but visit a flower for the nectar and pick up pollen unintentionally. The plant, of course, does intend this. As the animal visits another flower, the pollen on its body will drop off and fertilize the female parts of the second flower so it can bear fruit.
pollen grains horticulture animal and human remains
Hawk Moth
No, the animal version of pollen is sperm.
pollen
The worker bees go out to collect pollen and nectar which they bring back to the Hive for food and to make honey. Honey bees eat honey and pollen as their primary food, but they also gather liquids and juices from plant and fruit exudates. When honey bees come across insects that secrete honeydew, they gather the liquid and store it as honey. When pollen, nectar, or honeydew aren't available, honey bees can collect and store plant spores and dusty animal feed as well.
the pollen from the bees that they gather from the flowers.
Oxygen is everwhere. On earth, in the air, and on land. The animal does not need to gather oxygen.
Pollen is the plant equivalent to animal sperm.
Bees gather pollen, packing it into a small pocket on their legs, mixing it with nectar from flowers. This mix, known as bee pollen or bee bread is used to feed workers that stay at the beehive.
To collect pollen from flowers effectively, gently shake the flower over a clean surface or container to release the pollen. You can also use a small brush or cotton swab to carefully gather the pollen from the flower's anthers. Be sure to handle the pollen delicately to avoid damaging it.
Wind moves pollen for some plants like grass and corn. Animal pollinators move pollen for many flowering plants.
Insects, wind, animal fur and water.