Which of the following statements regarding cilia is not correct?
Which of the following statements regarding cilia is not correct?
cilia contain an outer ring of nine doublet microtubules surrounding two single microtubules.
the organized beating of cilia is controlled by fluxes of $\mathrm{Ca}^{2+}$ across the membrane
cilia arc hair-like cellular appendages
microtubules of cilia are composed of tubulin
Solution
Cilia are minute, hair-like processes on the surface of protozoans or on metazoan cells. Each cilium contains a peripheral circle of nine doubled microtubules arranged around two single microtubules. Each microtubule is composed of tubulin proteins. The mechanism of ciliary movement is not completely understood. The fluxes of $\mathrm{Ca}^{2+}$ across the membrane are not responsible for controlling the organised beating of cilia.