Cilia are tail-shaped cytoplasmic outgrowths found only in eukaryotic cells that aid in locomotion, while microvilli are protrusions of the cell membrane that used the surface area of ​​eukaryotic cells for absorption.

Comparative chart

What are cilia?

The surface of most cells has extensions that are used in movement, absorption, phagocytosis, etc. Cilia and microvilli are two protoplasmic extensions of cells. Cilia is the plural of cilium. These structures are mobile or immobile. The motile cilia can beat in one direction so that the body can move the entangled particles from the surface. Celia is also present in some other specialized cells called sensory cells of the ear of a vertebrate. For example, normal cilia are surrounded by actin-based stereocilia that are responsible for providing initial sensory input for hearing. These projections are also part of other organelles along with flagella, which is called undulipodia. The core of this structure is made up of microtubules uniformly arranged in a longitudinal orientation known as the (9 + 2) orientation. 9 + 2 means that the nucleus of each cilium contains nine microtubules doubly present in the periphery and two single microtubules in the center. Each cilium originates from a unique structure called the basal body. The basal body has different microtubule arrangements. The basal body has nine microtubules that are present in triplets without central tubules rather than the peripheral arrangement of nine tubules in a cilium nucleus. 9 + 2 means that the nucleus of each cilium contains nine microtubules doubly present in the periphery and two single microtubules in the center. Each cilium originates from a unique structure called the basal body. The basal body has different microtubule arrangements. The basal body has nine microtubules that are present in triplets without central tubules rather than the peripheral arrangement of nine tubules in a cilium nucleus. 9 + 2 means that the nucleus of each cilium contains nine microtubules doubly present in the periphery and two single microtubules in the center. Each cilium originates from a unique structure called the basal body. The basal body has different microtubule arrangements. The basal body has nine microtubules that are present in triplets without central tubules rather than the peripheral arrangement of nine tubules in a cilium nucleus.

Microvilli are the plural of microvilli. Microvilli are present in three types of cells specialized in absorption. The first site is the striated border of the intestinal epithelium; the second site is the brushed border of the proximal tubule of the kidney, while the third site is the epithelium of the gallbladder. Microvilli have tiny fibers called actin filaments that run parallel to each other along the microvilli. The filaments are attached to each other and to the cell membrane by proteins. These proteins run perpendicularly through the actin filaments. The microvilli are held together to form bundles by crosslinking proteins known as villin and fimbrin. The main function of the microvilli is the absorption of substances. Cells produce these microfilaments to improve the absorption surface on the intestinal surface, to participate in the digestion of carbohydrates, and to transport materials that are absorbed. Microvilli are packed in large quantities, making their appearance resemble a brush. These brush edges are present on the luminal surfaces of the intestinal epithelium, for absorption.

Key differences

1. Both cilia and microvilli contain protein fibers that extend outward to shape the structure.
2. Cilia are longer and larger in diameter than microvilli.
3. Cilia are made up of microtubules that contain (9 + 2) ultrastructure. Microvilli are made of microfilament that lacks ultrastructure (9 + 2).
4. The cilia are not surrounded by a layer of glycocalyx. The microvilli are surrounded by a layer of glycocalyx.
5. The cilia taper distally. The microvilli are extremely thin and short.
6. Cilia are used in the movement of cells or objects on the surface of cells; Microvilli improve the surface area of ​​the cell and increase the rate of diffusion of materials into the cell.
7. Cilia are found on the surface of columnar epithelial cells in the uterine tube or respiratory tract, while microvilli are present on the surface of columnar cells in the renal tubules and small intestine.