Explanation

Birds have a gizzard.

It is a muscular organ that grinds food.

It often with the help of ingested stones.

They lack teeth and a urinary bladder.

Explanation

Red light is most effective in enhancing cell division and growth in plants.

It plays a key role in photosynthesis and photomorphogenesis.

Explanation

The nitrogen cycle includes: ammonification, nitrification, denitrification, and nitrogen fixation.

Calcification is related to calcium cycle, not nitrogen cycle.

Explanation

Vascular cambium and cork cambium are lateral meristems.

They are responsible for secondary growth (increase in girth) of plants.

Explanation

Fossils provide direct evidence of past life forms and evolutionary changes over time.

They show transitional forms and the progression of species.

Explanation

Hydrophytes are plants adapted to live in water or very moist environments.

Examples: Hydrilla, Water Lily.

Explanation

Glycolysis breaks down glucose (6C) into two molecules of pyruvic acid (3C each).

This process occurs in the cytoplasm and produces ATP and NADH.

Explanation

Chloroplasts have an outer and inner membrane, enclosing the stroma and thylakoids.

They are the site of photosynthesis in plant cells.

Explanation

Amphibians are cold-blooded vertebrates that live both in water and on land.

Toads undergo metamorphosis from aquatic larvae (tadpoles) to terrestrial adults.

Explanation

Annelids (e.g., earthworms) excrete nitrogenous waste through nephridia.

Nephridia are tubular excretory structures that filter body fluids.