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.
Chemicals and Radiation Linked to Breast Cancer. In our daily lives we are exposed to toxic chemicals and radiation from a wide range of sources, and large and growing body of scientific evidence tells us that some of these exposures can increase breast cancer risk.Exposures to breast carcinogensâchemicals that directly cause breast cancerâare an obvious concern.hemicals and Radiation Linked to Breast Cancer. In our daily lives we are exposed to toxic chemicals and radiation from a wide range of sources, and large and growing body of scientific evidence tells us that some of these exposures can increase breast cancer risk.