Atom refers to a tiny particle, which is the basic building block of all the substances and whose properties determine the characteristics of an element made up of only of those atoms.
All the living and nonliving matter in this world are made up of atoms and elements. Everything in the universe is matter, and matter comprises elements. Some of the elements are important to living things.
Elements are formed by atoms, and atoms comprise protons, electrons, and neutrons. The number of protons in an element's atom signifies the identity of the element.
<span>Sodium channels close when not occupied
</span><span>Sodium ions diffuse through and enter the cell.
</span>
Then they leave the cell.
The sodium diverts in the cell layer have receptor locales for acetylcholine.
<span>repressors as well as by transcriptional activators.</span>
Answer:
pericardium
Explanation:
A double-walled membrane, the pericardium, separates the right and left chambers, preventing oxygen-rich blood from mixing up with the one without oxygen. So, the heart functions go smoothly. Deoxygenated blood enters the right atrium.