Question: where do sperm gain the ability to​ swim

title: Sperm motility
text: Sperm movement is activated by changes in intracellular ion concentration . The changes in ion concentration that provoke motility are different among species . In marine invertebrates and sea urchins , the rise in pH to about 7.2 -- 7.6 activates ATPase which leads to a decrease in intracellular potassium , and thus induces membrane hyperpolarization . As a result , sperm movement is activated . The change in cell volume which alters intracellular ion concentration can also contribute to the activation of sperm motility . In some mammals , sperm motility is activated by increase in pH , calcium ion and cAMP , yet it is suppressed by low pH in the epididymis . 

Answer: answer: Sperm movement is activated by changes in intracellular ion concentration, the ion concentration that provoke motility is different among species .  In some mammals , sperm motility is activated by an increase in pH , calcium ion and cAMP.
answer: .