Plz hlp has to do with lilies: how many chromosomes would a pollen grain have compared to an ovule?

Your sentence is hard to understand but, if I am understanding correctly it has half the number of chromosomes 

The glomerulus is sandwiched between two arterioles - afferent arterioles deliver blood to the glomerulus, while efferent arterioles carry it away. Constriction of efferent arterioles as blood exits the glomerulus provides resistance to blood flow, preventing a pressure drop, which could not be achieved if blood were to flow into venules, which do not really constrict. The two arterioles change in size to increase or decrease blood pressure in the glomerulus. In addition, efferent arterioles are smaller in diameter than afferent arterioles. As a result, pressurized blood enters the glomerulus through a relatively wide tube, but is forced to exit through a narrower tube.