Question

How many terms in the column are associated with stonewort?
Protandrous, Gynandrous, shield cells, coronary cells, tube cells, Archegoniopores, Globule, monoecious.
A.5
B.6
C.7
D.4

Answer 1

Hint: Charales is an order of freshwater algae which comes in the division of Chlorophyta and are commonly known as stonewort. They are called stonewort because the plant can become coated in lime while the stem is the central stalk which contains the large, multinucleated cell.

Complete answer:
 The stonewort mostly grows in the freshwater environment all over the world and they consist of large macroscopic thalli which grow up to 120 cm in length. They are branched, multicellular and use chlorophyll for the process of photosynthesis. They are distinctive as they have a whorl of small branchlets at each node in the stripe. These whorls show the phenomenon of cytoplasmic streaming and it is caused by the presence of microfilaments which are found inside the cell. There are about 400 species of stonewort found all over the world. Stoneworts are the main plant life of some of the volcanic basin lakes of Nicaragua and in some conditions, it is found in the depth of about more than 20 m.
They are generally found in the clear freshwater where they can attach to the substrate by rhizoids. They are mostly found in the freshwater where the nutrients content is comparatively lower or medium and they disappear due to eutrophication. The internodes of the stoneworts are composed of one cell which contains a single nucleus and the male globule has an outer layer of shield cells which is sterile. They can be monoecious or dioecious. The stem of the stoneworts contains a chain of single tube-like cells while there are no connective tissues present.
Hence, the correct answer is D.

Note: The stonewort is composed of six genera and they are generally submerged and attached to the muddy bottoms of fresh or brackish rivers or lakes. They give the food and the habitats for the fish and other aquatic animals.