Answer:
The correct answer is: Electrical impulses in the heart cause the muscles to contract.
Explanation:
The heart contracts thanks to a series of electrical impulses that travel through the muscles of this organ. The electrical impulse begins in the SA (sinoatrial) node and is transmitted to the muscles that conform the left and the right atria to produce their contraction which will make the atria pump the blood to the ventricles. When the electrical impulse reaches the AV node and then the Bundle of His, this information will transmit to both ventricles and will produce their contraction as well.
The only muscle tissue capable of stimulating their own contractions is the muscle in the heart, the myocardium, thanks to the existence of "pacemaker cells" that are located in the SA node.
The waves in the ECG represent the depolarization of the atria, depolarization of the ventricles, and repolarization of the ventricles.
It’s cranky and white shaped where it’s pretty shiny and crystals inside them where they spark off your eyes
Outdated systems, unskilled workers, poor quality of raw water <span>make it hard for Eastern Europe to improve the quality of its water.</span>
Rough endoplasmic reticulum is the site of the synthesis of proteins destined for export from the cell.
Answer:
Answered
Explanation:
When DNA is compacted by histone into 10-nm and 30-nm fibers, the DNA is unable to interact with proteins required for gene expression. Therefore, to allow for these proteins to act, the chromatin must constantly alter its structure. So, the process that contribute to the dynamic activity of methylation and phosphorylation of histone tails.