EVERYDAY SCIENCE

Detailed explanation-1: -The plasma membranes of cells that specialize in absorption are folded into fingerlike projections called microvilli (singular = microvillus).

Detailed explanation-2: -The motile cilium is a complex organelle that is typically comprised of a 9+2 microtubule skeleton; nine doublet microtubules surrounding a pair of central singlet microtubules.

Detailed explanation-3: -Microtubules are responsible for a variety of cell movements, including the intracellular transport and positioning of membrane vesicles and organelles, the separation of chromosomes at mitosis, and the beating of cilia and flagella.

Detailed explanation-4: -In eukaryotic cells, cilia and flagella contain the motor protein dynein and microtubules, which are composed of linear polymers of globular proteins called tubulin.

Detailed explanation-5: -The function of cilia is to move water relative to the cell in a regular movement of the cilia. This process can either result in the cell moving through the water, typical for many single-celled organisms, or in moving water and its contents across the surface of the cell.