NEET BIOLOGY

Detailed explanation-1: -Sponges have several cell types: * Choanocytes (also known as “collar cells"), flagellated cells which function as the sponge’s digestive system, are remarkably similar to the protistan choanoflagellates. The collars are composed of microvilli and are used to filter particles out of the water.

Detailed explanation-2: -Sponges and flagellate protists are both types of living organisms. Both are made up of eukaryotic cells, which are complex and have many organelles. Sponges are found in marine ecosystems, and many flagellate protists live in aquatic areas as well.

Detailed explanation-3: -Within the canals of the sponge, chambers are lined with specialized cells called choanocytes, or collar cells. The collar cells have a sticky, funnel shaped collar and a hairlike whip, called a flagellum.

Detailed explanation-4: -Choanocytes (also known as “collar cells") are cells that line the interior of asconoid, syconoid and leuconoid body types of sponges that contain a central flagellum, or cilium, surrounded by a collar of microvilli which are connected by a thin membrane.

Detailed explanation-5: -This is the best answer because protist choanoflagellates resemble specialized flagellated cells called choanocytes (aka collar cells) that line the water canals of sponges. Choanocytes resemble choanoflagellates in that both possess a collar that surrounds flagella.