Final answer:
In nonvascular plants like liverworts, hornworts, and mosses, structures such as rhizoids perform similar functions to roots, and leaf-like photosynthetic tissues serve the same purpose as leaves do in vascular plants. These plants also have stalks which resemble stems and produce spores analogous to seeds.
Step-by-step explanation:
Similar Structures in Nonvascular Plants
Nonvascular plants, such as liverworts, hornworts, and mosses, lack the complex vascular tissue system found in more advanced plants. Instead of having true leaves, they possess leaf-like photosynthetic tissues, which function similarly to leaves by carrying out photosynthesis. These leaf-like structures may be lobed or ribbon-like, especially in liverworts. Mosses, while also nonvascular, have structures more closely resembling leaves encircling a central stem-like part. Nonvascular plants produce spores for reproduction, which can be compared to seeds in vascular plants. The role of roots is fulfilled by rhizoids, which are fine, hair-like structures that anchor the plant and help in water and nutrient absorption.
As for the structures in question: rhizoids can be likened to roots due to their anchoring and nutrient absorption functions, while stalks in nonvascular plants, especially in liverworts, are somewhat similar to stems in vascular plants as they support the plant. However, it's essential to note that these nonvascular structures are more primitive and less specialized compared to their vascular counterparts. Nonvascular plants rely heavily on their immediate environment for moisture due to their lack of a vascular system, which limits their size and habitat range.