Guard cells: control the size of a water vacuole roots take up water control the size of stomata support the stem of the plant

Hey there!

The purpose of guard cells is to control the opening and closing of the Stomata, keeping it the correct width, or size.

Therefore, your correct answer would be Option 3, control the size of the Stomata.

Hope this helps!

what's the rest of the question

both male and female gametes are produced by meiosis of the germ cells. therefore, both male and female gametes are haploid. one male and one female gamete unite during the fertilization to form the diploid zygote. in seed bearing plants, pollen grain is the male gametophyte, which produces sperm cells.