GAS VACUOLES are present in CYANOBACTERIA, GREEN And PURPLE SULPHUR BACTERIA..INCLUSION BODIES store food materials but they lack membrane. PILLI are same hair like structures that help in attachment of bacteria to any substratum.. algae have cell wall made of galactans ,mannans and calcium carbonate.. There fore option D is correct

Gas vacuole absent in cyanobacteria

Gas vacuoles are important organelles found in some bacteria, particularly in aquatic environments. They are gas-filled structures that provide buoyancy to the cells, allowing them to move up and down in the water column. However, gas vacuoles are absent in cyanobacteria. Cyanobacteria are a group of photosynthetic bacteria that are capable of oxygenic photosynthesis. They have other adaptations for buoyancy, such as the production of gas vesicles, which are different from gas vacuoles.

Inclusion bodies store reserve material with unit membrane

Inclusion bodies are intracellular structures that store reserve materials in bacteria. These materials can include glycogen, lipids, polyphosphates, and sulfur. Inclusion bodies are typically surrounded by a unit membrane, which separates them from the cytoplasm. This membrane helps to protect the stored materials and regulate their release when needed.

Pili are small bristle-like organelles

Pili are elongated, filamentous structures found on the surface of many bacteria. They are composed of proteins called pilins and are involved in various functions such as attachment to surfaces, twitching motility, and conjugation. Pili are not considered organelles as they are not membrane-bound structures. Instead, they are external appendages of bacterial cells.

Algae have a cell wall with galactans, mannans, and calcium carbonate

Algae are a diverse group of photosynthetic organisms that can be found in various habitats, including freshwater, marine environments, and even on land. They have cell walls that provide structural support and protection to the cells. The composition of the cell wall can vary depending on the type of algae, but it often contains polysaccharides such as galactans and mannans. These polysaccharides contribute to the strength and flexibility of the cell wall. In addition, some algae, particularly those in marine environments, may also have cell walls that contain calcium carbonate, which further enhances the rigidity of the cell wall.

Overall, the correct statement is option 'D' - Algae have a cell wall with galactans, mannans, and calcium carbonate.