Guard cells become turgid when water flows in concurrently with
guard cells become turgid when water flows in concurrently witha.potassium ions.b.calcium ions.c.chloride ions.d.protons.e.sodium ions.

The correct answer is letter A. Potassium makes guard cells become turgid when water flows within this protective barrier. This happens so that the plant can perform photosynthesis even without the presence of direct sunlight. The pores of the cells start to contract and conserve water so that the plant can use it later on.

"Males who inherit the mutation get the disease because they have no second dystrophin gene to make up for the faulty one. Early in the embryonic development of a female, either the X chromosome from the mother (maternal X) or the one from the father (paternal X) is inactivated in each cell."

(courtesy https://www.mda.org)