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Which of the following statements about the structure of microtubules is false?

A) Microtubules are built from proto filaments that come together to make a hollow structure.
B) a-Tubulin and B-tubulin are covalently bound to make the tubulin dimer that then assembles into protofilaments.
C) The two ends of a protofilament are chemically distinct, with a-tubulin exposed at one end and B-tubulin exposed at the other end.
D) Within a microtubule, all protofilaments are arranged in the same orientation, giving the microtubule structural polarity.

User Gints
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Final answer:

The false statement about microtubule structure is that a-tubulin and B-tubulin are covalently bound.

Step-by-step explanation:

The false statement about the structure of microtubules is B) a-Tubulin and B-tubulin are covalently bound to make the tubulin dimer that then assembles into protofilaments.

In reality, a-tubulin and B-tubulin do not covalently bind to form the tubulin dimer. Instead, they non-covalently associate with each other. The tubulin dimer then assembles into protofilaments, which come together to form the hollow structure of the microtubule.

User Tmcallaghan
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