What is the flagella and cilia?

Answer 1

Cilia and flagella are both hair-like structures that extend from the surface of the cell, where they assist in movement.Cilia are short and more numerous than the longer flagella. They both have a membrane on their outer surface and have an internal structure of nine pairs of microtubules around two central tubules.

Sources:

Postlethwait, John H., and Janet L. Hopson. Modern Biology. Orlando, FL: Holt, Rinehart and Winston, 2009. Print.

Answer 2

Cilia (singular: cilium) are tiny organelles (like organs for large creatures, only small and not made of individual cellular components, IE, all part of a single cell) that form on the outer surface of the cell wall and are used by the cell to move around or to manipulate things. This typically occurs in cells that are autonomous, such as single-celled organisms, but can also occur in cells that regulate the immune system of creatures. A cell can have many cilia. They look sort of like 'hair' on the cell.

Flagella (singular: flagellum) are slightly larger, but serve similar functions as cilia. The difference being the size (Larger than cilia, but still part of a single cell), the number (generally very few, and usually only one to a cell), and their ability to manipulate things (they don't. They serve only as motors for the cell). These look like a 'tail' on a cell.

Some single celled organisms have several flagella, however these are functionally the same as cilia, and only distinguished as flagella due to length. This is mostly a eukaryote feature.

Both cilia and flagella have some secondary functions that are more passive, such as acting as sensory probes in detecting heat, chemicals, etc.

Wikipedia, while not infallible, has some very good information on cilia, flagella, and various other physiological and biological structures.

Answer 3

Cilia and flagella are made of microtubules that are bundled together in a particular pattern. Some are in the center and others are around the outside in a circle of bundles.

Answer 4

Cilia are numerous short hair-like extensions designed to move substances across the surface of the cell. A flagellum is a singular whip-like extension used to propel a cell.