Zoology MCQs for NEET — Practice Questions with Answers

The text states: 'During urine formation, the tubular cells secrete substances like H+, K+ and ammonia into the filtrate. Tubular secretion is also an important step in urine formation as it helps in the maintenance of ionic and acid base balance of body fluids.'

According to the context: 'Collecting Duct: ...It also plays a role in the maintenance of pH and ionic balance of blood by the selective secretion of H+ and K+ ions (Figure 16.5).'

The text clearly states: 'Reabsorption of water also occurs passively in the initial segments of the nephron (Figure 16.5)' and '...whereas the nitrogenous wastes are absorbed by passive transport.'

The context explains: 'Proximal Convoluted Tubule (PCT): PCT is lined by simple cuboidal brush border epithelium which increases the surface area for reabsorption.'

The text mentions: 'Collecting Duct: ...This segment allows passage of small amounts of urea into the medullary interstitium to keep up the osmolarity.'

The summary explicitly states: 'Urine formation involves three main processes, i.e., filtration, reabsorption and secretion.'

According to the NCERT text, 'Molluscs are terrestrial or aquatic (marine or fresh water) having an organ-system level of organisation.' This indicates that Phylum Mollusca exhibits an organ-system level of organization.

The NCERT text states, 'The molluscs have a soft body surrounded by an external calcareous shell.' and further, 'Body is covered by a calcareous shell and is unsegmented with a distinct head, muscular foot and visceral hump.' This clearly indicates the presence of a calcareous shell and unsegmented body as characteristics of Mollusca.

The NCERT text explicitly states, 'This is the second largest animal phylum (Figure 4.13).' in reference to Phylum Mollusca.

The NCERT text mentions, 'The space between the hump and the mantle is called the mantle cavity in which feather like gills are present. They have respiratory and excretory functions.' Thus, feather-like gills perform both functions.