<span>a mature haploid male or female germ cell that is able to unite with another of the opposite sex in sexual reproduction to form a zygote. b.
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Ventilation is the act of moving/pushing air into and out of the lungs.
I think the best answer would be white blood cells
A cross bridge cycle occurs when actin (A) combines with myosin (M) and ATP to produce force, adenosine diphosphate (ADP) and inorganic phosphate (Pi). The cross bridge cycle is a series of molecular events that occur after excitation of the sarcolemma.