what is the structure of mature anthridium of polytrichum? Required briefly explanation for 5 marks plz any one
Answers
Explanation:
Occurrence
Polytrichum have worldwide distribution. They are very common in cool temperature and tropical regions. Plants live in cool and shady places.
General structure
The main plant body is gametophyte. The adult plant consists of two parts: rhizome and upright leafy shoot.
1. Rhizome: It is horizontal portion and grows underground. It bears three rows of small brown or colourless leaves. It also bears rhizoids. The cells are rich in protoplasm and oil globules.
2. Upright leafy shoot: The leafy shoots are much longer. It is the most conspicuous part of the plant. It arises from rhizome. These branches consist of central axis. These branches bear large leaves arranged spirally.
3. Leaves: Leaves have broad bases. Leaves in the upper portion are green. But the lower ones are brown. Each leaf has a broad. colourless sheathing leaf base and narrow distal limb. The mid-rib forms the major part of the leaf. These leaves possess extra photosynthetic tissue in the form of closely set vertical plates of green cells. These are known as lamellae. Green lamellae act as additional photosynthetic tissue.