Diversity in Living Organisms

Plants are autotrophic (make their own food through photosynthesis), while fungi are heterotrophic (obtain nutrition from external sources). Both plants and fungi have cell walls and nuclei, so these cannot be distinguishing features. The mode of nutrition is the fundamental difference.

Algae have an undifferentiated plant body (thallus) and lack vascular tissue (xylem and phloem). Neem, Cycas, and Cedrus are all vascular plants with well-developed conducting tissues and differentiated plant structures. Algae represent the simplest plant form.

Pteridophytes (ferns) have vascular tissue, embryos, and rhizomes. Rhizoids are root-like structures found in bryophytes, not pteridophytes.

Thallophytes (algae) have chlorophyll for photosynthesis. They lack xylem, fruits, and flowers.

Bryophytes have rhizoids instead of true roots. They anchor the plant and absorb water.

Virus is an acellular organism.

In a prokaryotic cell DNA is circular and lies free in the cytoplasm.

All the animals, i.e. star fish, tapeworm, hydra, spider, sponges and planaria have power to regenerate.

Fresh water sponges reproduce by gemmule formation.

This is the correct answer. The process of obtaining food by amoeba is called phagocytosis. It means 'cell feeding'.

Plants are multicellular eukaryotes with cell walls made of cellulose. This is a defining characteristic of the Plantae kingdom. Fungi have cell walls made of chitin, not cellulose. Protists can be unicellular or multicellular but don't all have cellulose walls. Animals don't have cell walls at all.

Kingdom Protista is characterized by unicellular eukaryotic organisms. This includes protozoans, algae, and other single-celled eukaryotes. Fungi can be unicellular (yeasts) or multicellular. Plantae and Animalia are predominantly multicellular kingdoms.

Protists exhibit diverse modes of nutrition. Some are autotrophic (like algae that photosynthesize), while others are heterotrophic (like amoeba that ingest food). This diversity is a key characteristic of Kingdom Protista, making 'Both of (A) and (B)' the correct answer.

Aristotle classified organisms primarily based on their habitat - whether they lived on land, in water, or in air. This was a simple classification system based on where organisms lived, rather than their internal characteristics like cellular structure or nutrition. Modern classification is based on multiple criteria including cellular organization and phylogeny.

Protozoans are single-celled eukaryotic organisms that belong to Kingdom Protista. They are not monerans (which are prokaryotic), nor are they plants or fungi. The term 'protozoan' specifically refers to animal-like protists that are typically heterotrophic and motile.