Answer:
Power stroke (myosin head bends) coupled with the release of ADP and phosphate
Explanation:
Muscle contraction results from myosin heads adhering to actin and attracting it inwards. It uses ATP. Myosin adhers to actin at a binding site of its globular actin protein and adheres at another binding site for ATP (hydrolyzed ATP to ADP, Pi and energy)
ATP binding prompts myosin to detach from actin, ATP is changed to ADP and inorganic phosphate, Pi by ATPase. The energy formed at this process orientates myosin head to a “cocked” direction.
The myosin head goes in the direction of the M line, holding the actin with it in the process causing the filaments to orientate nearly 10 nm in the direction of the M line--- power stroke (force is produced), the sarcomere reduces in length and the muscle contracts.
Note: The power stroke is seen when ADP and phosphate disattaches itself from the myosin head.
At the terminal point of the power stroke, the myosin head as low-energy, followed by ADP release.
The attached image shows the cross-bridge muscle contraction cycle, which is activated by Ca2+ sticking to the actin active site. And how actin moves in relation to myosin.
<span>Somatic mosquito cells have 6 chromosomes. Its gamete has 3 chromosomes.
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Mosquitoes have 6 number of chromosome but when mosquitoes<span> make sperm or egg </span>cells<span>, meiosis reduces the </span>chromosome<span> number to 3.
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*the chromosome number in somatic body cells of a mosquito --- 6.
<span>the haploid (n) number is 3.
the diploid (2n) number is 6.</span>
Answer:
The correct answer is option a, that is, the thrM and thrN would be transcribed at high levels in comparison to non-mutant.
Explanation:
Based on the given information, in the existence of thorain the expression of thrM and thrN will be prevented as thorain functions as a negative regulator. In case, if the gene, which codes for thorain, that is, thrL gets mutated, the coding for the functional thorain would get prevented.
With the encoding of the non-functional thrL protein, there would be an enhancement in the expression of thrN and thrM genes and it will get transcribed at higher levels in comparison to the non-mutant or the wild-type.