Troponin-tropomyosin molecules prevents a muscle contraction from occurring when the muscle is at rest.
<h3>What is 
muscle contraction?</h3>
The activation of tension-producing regions within muscle cells results in muscular contraction. Because muscle tension can be created without changes in muscle length, such as when holding something heavy in the same position, muscle contraction does not always imply muscle shortening in physiology. Muscle relaxation, or the return of the muscular fibers to their low tension-generating state, occurs after a muscle contraction has finished.
Both length and tension can be used to characterize muscle contractions. If the muscle tension varies but the muscle length doesn't, the muscle contraction is said to be isometric. A muscle contraction is isotonic, however, if the tension in the muscle remains constant during the contraction.
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brainly.com/question/10115123
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Answer:
With the concentration gradient through passive Transport
Explanation:
I haven't taken biology recently, but if I'm not mistaken, cells that use ATP can only passively do things.
 
        
             
        
        
        
I would like to talk about a birthday celebration that I attended 2/3 months ago. It was one of my friends' birthday who turned 25 that day. My friend's name is Ryan and his parents wanted to celebrate his birthday just before his departure to United Kingdom. Ryan invited almost all of his close friends and 6-7 of us attended the birthday celebration together. Apart from us, there were as many as 100 other people present on the occasion. I did not know most of them but my guess is that they would be mostly Ryan's relatives, neighbors and his father's colleagues.
The party was celebrated at my friend's house at tohana. We went there together and bought a present for the Ryan. After reaching there, Ryan and his parents warmly welcomed us. Later Ryan introduced us to his relatives and to some of his neighbors. We were astonished when we saw the huge birthday cake. 25 candles of different colors were lit around the cake and the whole house was redecorated for the occasion. Anybody could say that some occasion was going on in this house without knowing anything.
We sang the birthday song when Ryan cut the cake. We congratulated him and wished him a prosperous life ahead. Then we ate cake and had a good feast. The foods were delicious and good. We, friends of our circle, went to visit a nearby place and sang different songs. In the evening we went to Ryan's house again and attended a raffle draw. That was a very exciting part of the birthday celebration. Then after few minutes we left the party and went our homes.
        
             
        
        
        
Which is not an emotional reaction to stress?
picking a fight
feeling moody or aggressive
noticing your heart racing
bursting into tears more often