AP BIOLOGY

Detailed explanation-1: -Nonvascular Plants. Nonvascular plants (often referred to collectively as the bryophytes) include three groups: the mosses (Bryophyta), approximately 15, 000 species; liverworts (Hepaticophyta), approximately 7500 species; and hornworts (Anthocerophyta), approximately 250 species (Table 1).

Detailed explanation-2: -Nonvascular plants include liverworts, hornworts, and mosses. They lack roots, stems, and leaves. Nonvascular plants are low-growing, reproduce with spores, and need a moist habitat.

Detailed explanation-3: -Mosses and liverworts are small, primitive, non-vascular plants. They lack the conductive tissue most plants use to transport water and nutrients. Instead, moisture is absorbed directly into cells by osmosis.

Detailed explanation-4: -Mosses, and their relatives the hornworts and liverworts are regarded as the first true plants on dry land. These groups, collectively known as the bryophytes, are small and inconspicuous, damp-loving plants.