ANTIQUE VINTAGE 1930 SINGER TREADLE SEWING MACHINE & CABINETUp for sale is this 1930 Singer Treadle Sewing Machine (Model 99-13). It is in good condition, with some wood peeling on the corners and an arm missing from the lower flywheel, though still has its original belt.ebay.com.
{Ribs+Sternum = Rib cage}. Rib cage has 12 pairs of ribs or 24 in number. Ribs are divided in three categories on the basis of their size and their connections with the front side of skeleton. True ribs - First 7 pairs {1â7} of rib bones are called true ribs. They connect strernum {breast bone} with coastal cartilage in the front and to the spine at the back by ligaments. [coastal cartilage is elastic in nature and helps the ribcage to expand during respiration].
The ribcage forms part of the bodyâs respiratory system. It enables expansion of the chest cavity so that the lungs can expand and breathe in oxygen. The ribcage also encloses the thoracic cavity and helps protect the heart and lungs from damage. There are 24 ribs in the human body, divided into two sets of 12 curved, flat bones. Each one is attached by cartilage at the back to the thoracic vertebrae. The first upper seven ribs are known as 'true ribs' and are directly attached by cartilage to a long flat bone at the centre of the chest called the sternum (breastbone). The remaining pairs of ribs are known as âfalse ribsâ. The eighth, ninth and tenth ribs are also attached to the sternum but not directly.