Explanation

In echinoderms, water enters the water vascular system through a sieve-like structure called the madreporite.

This structure, often a small, light-colored plate, acts as an opening to the internal water-filled canals.

Water then flows through a series of canals, including the stone canal and radial canals, eventually reaching the tube feet.

Explanation

In bryophytes, the gametophyte generation is dominant.

This means the leafy, green, haploid structure that is typically seen is the gametophyte, which is the most visible and longest-lived part of the bryophyte life cycle.

The diploid sporophyte is generally smaller and dependent on the gametophyte for survival.

Explanation

Explanation

Explanation

The primary mode of movement in zooflagellates is flagellar movement.

Zooflagellates, also known as flagellates, are protozoa that use one or more flagella for locomotion.

These flagella are whip-like appendages that propel the organism through their environment.

Explanation

Cyanobacteria utilize phycobilins, specifically phycocyanin (blue) and phycoerythrin (red), as accessory pigments in addition to chlorophyll a.

These pigments help cyanobacteria absorb light across a wider range of wavelengths than chlorophyll a alone, enhancing their photosynthetic efficiency.

Explanation

Explanation

Viruses lack organelles like ribosomes, mitochondria, and Golgi apparatus.

They are simple particles composed of genetic material (DNA or RNA) and a protein coat.

They need to infect a host cell to use the host's ribosomes to replicate.

Explanation

Explanation

Cholesterol is embedded in the plasma membrane and helps regulate its fluidity, preventing it from becoming too rigid or too fluid.

It provides stability and flexibility, especially in eukaryotic cells.