Non-vascular plants include two distantly related groups: 1  Bryophytes-Bryophyta (mosses), Marchantiophyta (liverworts), and Anthocerotophyta (hornworts). 2  In these groups, the primary plants are the haploid gametophytes, with the only diploid portion being the attached sporophyte, consisting of a stalk and sporangium. In these groups, the primary plants are the haploid gametophytes, with the only diploid portion being the attached sporophyte, consisting of a stalk and sporangium. 2  Because these plants lack lignified water-conducting tissues, they can't become as tall as most vascular plants. 3  Algae-especially the green algae.
It is possible that welders are at greater risk of developing skin cancer than the general population, but there is a dearth of well designed studies in this area. The only major study of the relationship between arc welding and skin cancer risk did not reveal an increased incidence of skin cancer in welders.
Prostate cancer. It's not clear what causes prostate cancer. Doctors know that prostate cancer begins when some cells in your prostate become abnormal. Mutations in the abnormal cells' DNA cause the cells to grow and divide more rapidly than normal cells do.The abnormal cells continue living, when other cells would die.t's not clear what causes prostate cancer. Doctors know that prostate cancer begins when some cells in your prostate become abnormal. Mutations in the abnormal cells' DNA cause the cells to grow and divide more rapidly than normal cells do. The abnormal cells continue living, when other cells would die.