Diversity in Living Organisms

Three chambered heart is present in amphibians.

External ears (pinna) are present in mammals.

In 1969, R. H. Whittaker suggested the five kingdom classification on the basis of various factors.

The earth originated during this time period.

Human being is a multicellular animal, who shows division of labour.

Merino is a breed of sheep prized for its fine, soft wool used in high-quality textiles. Originating in Spain, Merinos produce the finest and most valuable wool of all sheep breeds. The breed is now raised worldwide, especially in Australia, for premium wool production.

It is a measure of overall diversity for the different ecosystems within a large region.

It shows the record of species (all plants and animals) at the risk of extinction. The IUCN maintains this book to provide data on population status of species around the world.

Option 3 is correct.

In the hierarchical biological classification system, Kingdom is the broadest category, encompassing all related organisms. The hierarchy from broadest to most specific is: Kingdom → Phylum → Class → Order → Family → Genus → Species. Humans belong to Kingdom Animalia, Phylum Chordata, Class Mammalia, etc.

Bacteria are prokaryotic organisms, meaning they lack a membrane-bound nucleus and other membrane-bound organelles. Their DNA floats freely in the nucleoid region. Eukaryotes (plants, animals, fungi) have membrane-bound nuclei, while bacteria are single-celled prokaryotes that reproduce by binary fission.

The skin does not merely protect the frog but helps in respiration.
Fine blood vessels run throughout the frog's skin; oxygen can pass through the membranous skin, thereby entering directly into the blood. When a frog submerges beneath the water, all its respiration takes place through the skin. Oxygen is obtained directly from the water.

These species no longer exist on earth.

Invertebrates are animals that lack a vertebral column (backbone or spine). This group includes diverse animals like snails (mollusks), beetles (arthropods), worms (annelids), jellyfish (cnidarians), and octopuses (mollusks). Vertebrates, like humans, dogs, and birds, have a backbone. The term 'invertebrate' comes from 'in-' meaning 'without' and 'vertebra' meaning 'joint' or 'backbone'.

Murrah is a high-yielding breed of water buffalo, originally from the Punjab region of India and Pakistan. It's renowned for its high milk production and superior dairy characteristics. Murrah buffaloes are black in color, have curved horns, and are widely used in dairy farming across India, particularly for ghee (clarified butter) production due to the high fat content in their milk.

In lower termites, cellulose (the main component of wood) is digested by protozoans living in their hindgut. These protozoans produce cellulase enzymes that break down cellulose into simpler compounds that termites can absorb. Higher termites lack protozoans and rely solely on bacteria and their own enzymes. Option C (both) is incorrect because the question specifically asks about termites in general, where protozoans are the distinctive answer.

The gelling agent in agar-agar is an unbranched polysaccharide obtained from the cell walls of some species of red algae.

 Bats and birds are both fliers but bat differs from bird in having diaphragm