At the onset of a muscle contraction, the presence of calcium triggers the opening of the Na-K channels in the membrane. Potassium is a calcium inhibitor, so as the potassium flows out of the cell, it eventually reduces the presence of calcium. This causes the closure of the Na-K channel (negative feedback mechanism). In a hypokalemic state, the lack of sufficient K doesn't inhibit the calcium channel, and in turn doesn't properly terminate the muscle contraction at the cellular level.
<span>After a fetus has developed for three months, what is its skeleton made of :
</span>
<span>The bones will be formed from the centers of ossification, cartilage will gradually be replaced by bone. during this time, ossification of the spine <span>continues.
</span></span>
When a person has the ability to practice health-enhancing behaviors & reduces risks, kit is referred to as a healthy life and is denoted as option B.
<h3>What is Healthy life?</h3>
This is defined as a type of living or lifestyle which reduces the risks of falling ill or premature death.
Examples of a healthy lifestyle include performing exercises and eating the right types of foods. Others however may include staying away from smoking and alcohol which reduces the risk of cancer and damage to other parts of the body.
Read more about Healthy life here brainly.com/question/17543848
#SPJ1
