Your heart is one of the most important muscles in your body. Each day, your heart beats about 100,000 times and, over your life span, about 2.5 billion times! The fibrous pericardium encases, protects and secures the heart. Inside the pericardium is the heart wall, and this is organized into three main layers. The outermost layer of the heart wall is the epicardium, which is also the innermost layer of the pericardium.
Several different languages are spoken in Mexico, with a large majority of the population fluent in Spanish while some indigenous Mexicans are monolingual in indigenous languages.he slow process of replacing Mexico's indigenous languages with Spanish began with the arrival of Spanish forces and colonists in Mexico in the 16th century.
Nahuatl is an Uto-Aztecan language spoken by about 1.5 million people in Mexico.The majority of speakers live in central Mexico, particularly in Puebla, Veracruz, Hildago, San Luis Potosi, Guerrero, Mexico (state), El Distrito Federal, Tlaxcala, Morelos and Oaxaca, and also in El Salvador.ost Nahuatl speakers also speak Spanish, with the exception of some of most elderly. Classical Nahuatl was the language of the Aztec empire and was used as a lingua franca in much of Mesoamerica from the 7th century AD until the Spanish conquest in the 16th century.