SA Node<span> which is also known as the sinus node, is the natural pacemaker of
the heart. It controls the heart rate by generating electrical impulses
and then sending electrical signals through the heart muscle, causing
the heart to contract and pump blood throughout the body. </span>
The SA Node is located in the outer layer of the right atrium of the heart, near the superior vena cava. It is made up of a group of cells (myocytes) positioned on the
wall of the right atrium, at the center of the heart and near the
entrance of the superior vena cava. These cells contract at a rate of
about 70-80 times per minute, which make up the natural heart beat.
The correct answer is "southerners." Sarah and Angelina Grimké's parents were slaveholders; while Sarah and Angelina never experienced slavery themselves, they viewed it firsthand, and from their own experience decided to advocate against slavery. This decision carried so much weight because overall, southerners didn't want to give up slavery.
Answer:
When a cold front overtakes a warm front, it creates what's called an occluded front that forces warm air above a frontal boundary of cooler air masses.
Explanation:
The presence of a cold front means that cold air is advancing and pushing underneath warmer air. This is because the cold air is ‘heavier,’ or denser, than the warm air. Cold air is thus replacing warm air at the surface.
Answer:
Due evolution, discoveries and having both characteristics.
Explanation:
The Kingdom of Life change due to evolution in the body of organisms, discoveries of new organisms that are different from plants and animals. There are some organisms that have both plant and animal characteristics so it can't be placed in plant or animal kingdom so that's why the kingdom of life changes from two kingdom system to 5 kingdom system.