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 surface temperature of white dwarf stars is higher than that of red super giants. White dwarf stars are extremely hot when they form, and they start cooling off as time goes by. Red supergiants, on the other hand, are enormous dying stars, and they are quite cool. So, having this in mind, white dwarves are hotter than red supergiants. Hope I helped! :) If it’s wrong then I’m sorry!
All the organic molecules produced by autotrophs CONTAINS ENERGY.
Autotrophs are plants that produce their own food using energy from the sun. Products produced by these autotrophs contain inherent energy which humans and animals absorb when they eat these products.
Water and minerals are absorbed into the blood in the colon of the large intestine.
