Question

In ulothrix, the shape of chloroplast is
a. Star- shaped
b. Cup-shaped
c. Girdle-shaped
d. Diffuse type

Answer 1

Hint: Ulothrix is green algae which generally lives in both marine and freshwater having unbranched and uniseriate filaments. Filaments are responsible for the movement as it lives in water. Cytoplasm consists of a single nucleus. Central region is occupied by a cavity called vacuole which contains cell sap. The chloroplast is a ring-like structure having ribbon-like shape or girdle shape.

Complete answer:
Ulothrix belongs to a family ulotrichaceae. The cells of plants are as broad as they are longer. Every cell has a distinct nucleus, a central vacuole, and thin chloroplast. Cells are end to end attached. Thallus is long, multicellular and unbranched. In most of the species, all the cells can form reproductive bodies. Reproduction process in Ulothrix occurs vegetatively by fragmentation and asexual reproduction occur by non-motile resting spores and motile spores i.e. zoospore. Sexual reproduction occurs by biflagellate gametes. Plant body is differentiated into mainly three regions which are – basal cell, apical cell and middle cell. Chloroplast consists of two to many pyrenoids one is U.rorida and another one is U.zonata. Pyrenoids are the structure found in many algae. Chloroplast is a plant organelles that convert light energy into chemical energy by which green plants prepare their food. The Peripheral region of cytoplasm is single girdle or band shaped. It may differ from species to species.

Hence, the correct answer is option (C).

Note: Ulothrix is a green algae having barrel shaped or cylindrical cells. The cell wall is composed of propectin and cellulose. It lacks its mucilage. As we see the plant cell structure it bears girdle shaped chloroplast.