Mini excavators comprise the smallest models available. This category includes: micro excavators that weigh as little as 800 kg or less; mini excavators that average around 3,000 kg; and midi versions that may be upwards of 6 tonnes. Mini excavators are perfect for construction jobs in small spaces and other lighter work.
The inner layer of the pericardium is attached to the heart muscle. A coating of fluid separates the two layers of membrane, letting the heart move as it beats. Your heart has 4 chambers. The upper chambers are called the left and right atria, and the lower chambers are called the left and right ventricles. A wall of muscle called the septum separates the left and right atria and the left and right ventricles.
Leave a comment Go to comments. Layers of the Heart Wall. The heart can be broken up into three major tissue layers: the endocardium, myocardium, and pericardium. Endocardium. The endocarium is the innermost, thin and smooth layer of epithelial tissue that lines the inner surface of all the heart chambers and valves.