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The illustration below is a basic phylogenetic tree for Kingdom Plantae. Answer

ID: 191758 • Letter: T

Question

The illustration below is a basic phylogenetic tree for Kingdom Plantae. Answer the following questions using the provided tree. 1. This organism serves as the root (basal taxon): 2. From an evolutionary perspective, this lineage of plants is the oldest a. Nonvascular Plants b. Seedless Vascular Plants c. Seed Plants 3. Mosses, hornworts and liverworts belong to this lineage: a. Nonvascular Plantsb. Seedless Vascular Plants c. Seed Plants 4. True or False? Ferns and horsetails fall within the Seed Plants" lineage.

Explanation / Answer

  1] Chlamydomonas.

This is a unicellular organism belonging to the Division - Thallophyta

Thallophytes are the lowest division in plant taxonomy and include plants which have a plant body as an undivided mass of cells called ' thallus'. They do not have a vascular system and include the simplest plants.

2. Option [a] Nonvascular plants

Reason-- Non flowering plants or 'Cryptogamae' includes three classes- Thallophyta, Bryophyta

and Pteridophyta. Of these, thallophytes and bryophytes do not have a vascular system. The vascular system [xylem and phloem] first make their appearance in pteridophytes which also show differentiation

of the plant body into root, stem and leaves.

3. Option [a] Non-vascular plants

Reason-- Mosses, liverworts and hornworts belong to the division Bryophyta.

Liverworts and hornworts appear as flat, green thylloid structures. Mosses show body differentiation into stem and leaves but they lack a proper root. Instead they have root like structures called rhizoids. Xylem and phloem [vascular tissues] are absent in all bryophytes.

4. FALSE

Reason-- Ferns and horsetails have naked embryos called spores. The reproductive organs of ferns and horsetails are very inconspicuous and they are therefore called cryptogamae meaning ' those with hidden reproductive organs' . They do not have seeds.