Substitutions, additions, or deletions of one or more nucleotides in the dna molecule are called
a. genetic variations
c. recombinant dna
b. gene mutations
d. dna fragmentation select the best answer from the choices provided

b. gene mutations.

Explanation:

The segment of DNA which can undergoes mutation is called muton and this is one of the definition of a gene. A permanent change in the DNA structure is called mutation. Mutation can affect from a single base pair to a large segment of a chromosome. The DNA sequence of a gene can be changed in a number of ways such as addition (by adding a piece of DNA), deletion (by removing a piece of DNA), and duplication in one or more nucleotide in in a DNA molecule. Gene mutations can change the function of many important proteins in the body.  

after a the power stroke, adp is released, but the cross-bridge formed is still in place. atp then binds to myosin, moving the myosin to its high-energy state, releasing the myosin head from the actin active site.