Hoarseness is a harsh, rough, raspy quality to the voice. Hoarseness is generally caused by irritation of, or injury to, the vocal cords. This trauma to the vocal cords leads to a change in the pitch of the voice. The voice box, or larynx, is the portion of the respiratory (breathing) tract containing the vocal cords that produce sound.
The gametophytes in seed plants, like pine trees and oak trees, are unisexual and microscopic. They are found inside part of the sporophyte and rely completely on the sporophyte for nutrients. For example, in a pine tree, the male gametophyte that produces sperm is found inside a pollen grain.lternation of generations is a type of life cycle found in all plants and some algae species. This process involves a multicellular diploid generation called a sporophyte and a multicellular haploid generation called a gametophyte.
Inside the pollen are two (or, at most, three) cells that comprise the male gametophyte. The tube cell (also referred to as the tube nucleus) develops into the pollen tube. The germ cell divides by mitosis to produce two sperm cells.