The hepatic portal vein is formed by the union of a) , which drains the b) , via the c) , which drains the d) . The e vein, which drains the lesser curvature of the stomach, empties directly into the hepatic portal vein.

answer: - b cells

explanation: -

so, the b cells mediate their action by identifying the antigens present on the surface of the pathogens and then producing antibodies in return to mediate its effect.

what are the options

answer: grassland biomes are closer to the equator and receive more rain.

grasslands are biomes that are dominated by grasses rather shrubs and trees. savanna are biomes that exhibit grasses, shrubs and small tree as vegetation. grasslands are located near the equator of the earth. these are found in north america. savanna biomes are found in africa, south america, australia and india. grassland exhibit moderate climatic conditions, it receives   amount of rainfall higher than savanna.   therefore, savanna exhibit dry and hot climatic conditions.

since there are no options posted i'll give you a few examples.

a dolphin's flipper, bird's wing, cat's leg.