Cortex Phloem Xylem- Хylem Pith Phloem (A) (B) Phloem Xylem Хylem Phloem (C) Leaf gap Leaf trace (D) FIGURE 21-29 Anatomy of fern stems is variable-not only from species to species, but also within a single plant. (A) In this Dennstaedtia and many other ferns, xylem forms a complete ring in transverse section. (B) Phloem occurs on both the exterior and interior of the xylem in ferns; phloem interior to xylem is extremely rare in seed plants (X20). (C) In this Adiantum, the vascular tissue makes almost a complete cylinder. A leaf gap occurs where vascular tissue moves to the leaves. Leaf gaps are characteristic of ferns; they do not occur in the microphyll line of evolution (lycophytes). (D) Members of the microphyll line of evolution, such as this Lycopodium annotinum, do not have pith (X20).

Exercise II Bryophyta: The Mosses Examine with the dissecting microscope the mosses that are available. The "leafy" plants are the gametophytes and any elongated structures growing above them are the sporophytes. (See text Figure 16-27, page 385.) 15. Label the following in Figure 5 below: spores, zygote, protonema, gametophyte, meiosis, female, male, sporophyte, archegonia, sperm, sporangium. Capsule (n) 9 "Bud" Mature (2n) Female (n) 1n 2n Young sporophyte (2n) gametophyte (n) 82 Antheridia gametophyte (n) Embryo (2n) water E88 Female -gametophyte (n) sperm Fertilization (2n) Figure 5. Moss Life Cycle (drawn by Stephanie Preising, SCSU '20) Obtain a gametophyte and observe its symmetry, its leaf like structures, its axis (pseudo- stem), and is rhizoids. Some species of mosses are unisexual; others are bisexual. The moss gametophyte originates as budlike structures that develop from a protonema (plural: protonemata), a system of branching filaments derived from a germinating spore.

Are geraniums herbs or woody plants? Do they ever form bark (as shown)?

Exercise II Bryophyta: The Mosses de Examine with the dissecting microscope the mosses that are available. The "leafy" plants are the gametophytes and any elongated structures growing above them are the sporophytes. (See text Figure 16-27, page 385.) 15. Label the following in Figure 5 below: spores, zygote, protonema, gametophyte, meiosis, female, male, sporophyte, archegonia, sperm, sporangium. € Capsule (n) Mature (2n) Female (n) 1n 2n Young sporophyte (2n) gametophyte (n) Antheridia gametophyte (n) 82 Embryo (2n) water Egg Female, gametophyte (n) sperm Fertilization (2n) Figure 5. Moss Life Cycle (drawn by Stephanie Preising, SCSU '20) Obtain a gametophyte and observe its symmetry, its leaf like structures, its axis (pseudo- stem), and is rhizoids. Some species of mosses are unisexual; others are bisexual. The moss gametophyte originates as budlike structures that develop from a protonema (plural: protonemata), a system of branching filaments derived from a germinating spore.

Stem of sub-merged hydrophytes is soft and weak because of (a) the absence of phloem (b) the absence of stomata (c) the absence of xylem (d) feebly developed supporting tissue and xylem

26. 27.

Part c

Can someone help me in my assignment :(

Cross-section of a pine stem: a. What are the secretory cells? b. what substances do secretory cells in pine produce? c. Which has more stomata, the upper or lower epidermis? Why?

Sclerophyllous foliage leaves like those in holly, barberry (as shown), and Yucca (as shown) have many unusual features. Do they live for 1 year or longer? They are more resistant to animals that might try to eat them. Why? What type of cells do they have that most leaves do not have?