Answer:
Muscle contraction thus results from an interaction between the actin and myosin filaments that generates their movement relative to one another.
Answer:
The correct answer will be options
1. The position of the tropomyosin threads shift
2. Exposing myosin binding sites
3. Allowing the myosin head to attach to the actin filament
Explanation:
Calcium plays an important role in the contraction of muscles especially in the formation of the cross-bridge between myosin and actin filaments.
In the presence of calcium, myosin head binds the actin filament as calcium binds to the troponin which changes the configuration of the troponin which releases the tropomyosin from the myosin-binding site on actin.
Once the myosin binding site is freed, myosin binds the site and causes muscle contraction due to ATP hydrolysis.
Thus, the selected options are the correct answer.
A concentration gradient must exist. hope this helps
<span>The principle that recessive genes will always be masked by dominant genes is Mendel's principle of Dominance. Alleles are different forms of genes and they can be dominant or recessive. According to Mendel's principle of dominance, dominant alleles mask the effects of recessive alleles. </span>
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