Which type of reins a rider uses, split reins or one rein, is a matter of personal preference. Split reins are commonly seen in the Western riding disciplines, although some Western riders might use one rein. Split reins are heavily preferred by most working cowboys and cowgirls.
Antimicrotubule agent, mitotic inhibitor Oncology An agent that inhibits cancer growth by stopping cell division Pharmacology A drug that inhibits or blocks mitosis in a particular phase of the cell cycleâeg, metaphase arrest caused by colchicine and vinca alkaloids. See Chemotherapy.
Site of Action. Mitotic (cell division) inhibitors. Does not bind to tubulin as other herbicides in this mechanism of action group do. Inhibits mitosis in late pro-metaphase by binding to another protein that is likely associated with tubulin.